Intellihot iN501 Water Heater Installation Guide

Installation Guide for Intellihot models including: iN401, iN501, iN501 Water Heater, iN501, Water Heater, Heater

4. Quick Reference Installation Guide

iN401 - iN501Quick Reference Installation Guide 12 May 2019 - Revision 00. 2. Open the gas supply valve, cold water valve, and hot water valve

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iN401-iN501-Installation-Manual

4. Quick Reference Installation Guide
4.1 Install the Water Heater
When installing the water heater, follow all local building codes and the current edition of the National Fuel Gas Code (ANSI Z223.1/NFPA 54) in the USA, or National Gas and Propane Installation Code (CAN/CGA B149.1) in Canada.
Note: For water heater installations in Massachusetts, refer to section, "17. Requirements for State of Massachusetts" on page 67.
1. Select an installation location For an interior or exterior location refer to section "5. Preparation Before Installation" on page 13.
2. Check the quality of the water to determine if additional treatment would be beneficial to the function and efficiency of the water heater. For additional information refer to section "5. Preparation Before Installation" on page 13.
3. Make all necessary gas connections. For additional information refer to section "6. Gas Connection" on page 14.
4. Make all necessary venting connections. For additional information refer to section "7. Air Intake Inlet and Exhaust Gas Outlet Pipe Connections" on page 19.
5. Make all necessary water connections. For additional information refer to section "8. Water Connections" on page 28.
6. Make all necessary electrical connections. "9. Electrical Power" on page 30.
Note: For additional electrical protection, the use of a surge protection device is recommended. Damage caused by power surges is not covered by the warranty.
7. If necessary, convert the water heater from the factory preset of using natural gas to using propane. Refer to "11. Natural Gas to Propane Conversion" on page 34 for the required instructions.
8. As part of the propane conversion process, the CO2 and CO values must be adjusted. This process is also required when installing the water heater at altitudes over 8,000 feet. This procedure should be performed only by a qualified technician. To check and/or adjust the CO2 and CO levels, refer to "10. Adjusting CO2 Level" on page 31.
9. If connecting multiple units together, refer to "13. Connecting Multiple Units" on page 47.
10. Fill out the Warranty Card and return it to Intellihot. For a copy of the card go to "19. Product Warranty" on page 70.

4.2 Pre-Startup Instructions
1. Recheck the hot and cold water lines, the gas line, condensate drain line, the fresh air inlet, and exhaust vent to make sure they are properly connected.

Exhaust Port

Air Intake Gas Inlet

Pressure Relief Valve
Hot Water Outlet

Recirculation Inlet Cold Water Inlet

iN401 - iN501 Quick Reference Installation Guide

Dec 2022 - Revision 01

2. Open the gas supply valve, cold water valve, and hot water valve.

5. Turn ON the power switch at the electrical junction box and turn ON the ON/OFF switch inside the front cabinet door. The water heater's display panel should turn ON.

Hot Water Valve

Gas Valve

Cold Water Valve
6. Follow the instructions in this manual and on the unit's display screen. For additional information refer to section "12. Operation" on page 36.
3. With the unit OFF, open a nearby hot water faucet and allow the water to run through the unit until all the air is removed from the water lines and from the water heater.
4. If multiple units are being installed, follow these instructions for each unit.

iN401 - iN501 Quick Reference Installation Guide

May 2019 - Revision 00

5. Preparation Before Installation
5.1 Selecting an Indoor Installation Site
Note: When installing the water heater, follow all local building codes and the current edition of the National Fuel Gas Code (ANSI Z223.1/NFPA 54) in the USA, or National Gas and Propane Installation Code (CAN/ CGA B149.1) in Canada when installing this product.
Note: For water heater installations in Massachusetts, refer to section "17. Requirements for State of Massachusetts" on page 67.
1. Select an interior location for the installation. Each installation is unique; therefore, take the time to find the best location for the water heater.
a. Install the water heater near locations that use hot water, such as bathroom, kitchen, or laundry room faucets.
b. Select a location that minimizes the length of the water pipe.
c. If the distances are long or if the faucet or appliance requires "instant" hot water, we recommend running a recirculation line back to the water heater from the farthest fixture.
d. Insulate the hot water supply and recirculation lines.
e. Select a location away from foot traffic and away from areas where dust, debris, chemical agents, or other combustible materials could accumulate.
f. Allow sufficient space for service and maintenance access to all gas, water, and drain connections.
g. Make sure the location meets all building code requirements.
2. Minimize the distance that the exhaust gas outlet and air intake inlet must travel to an exterior wall.
a. The exhaust vent outlet must not be located next to a walkway, near soffit vents, crawl space vents, or other areas where condensate (water vapor) could cause damage or create a hazard. Refer to the Venting Clearance Specifications section for additional information.
b. The fresh air inlet vent must be separated from the exhaust vent per guidelines in section "7. Air Intake Inlet and Exhaust Gas Outlet Pipe Connections" on page 19.
c. Contaminated or dirty air drawn into the intake pipe can damage the water heater. The warranty does not cover damage caused by airborne contaminants.

3. Locate the unit close to a drain and near gas and water connections.
The water heater produces a significant amount of condensate during normal operation and should be located near a suitable drain where damage from a possible leak will be minimal. Installing the water heater in a location without a drain will void the warranty and the manufacturer will not be responsible for any resulting water damages that may occur. For additional information, refer to the Condensate Line Installation section. 4. Locate the water heater and all the water pipes in an area where the ambient temperature always remains above freezing.
a. When the water heater is connected to an electrical power supply, it will automatically prevent the water from freezing inside the unit.
b. The unit's freeze protection system will not prevent the water in the external piping from freezing.
NOTICE
In cold climates, if there is a power failure, the unit's freeze protection system will not operate and can result in water freezing inside the heat engine. To prevent damage to the water heater, turn OFF the gas supply and inlet water valve. Drain the unit completely. Damage caused by freezing water is not covered by the warranty.
5. Select an appropriate location for the combustion air and exhaust pipes to exit the building, as shown in the Venting Clearance Specifications section in this manual.
6. Check the water quality.
Proper maintenance of the water heater is required to ensure that the water meets EPA quality standards. The following table shows the maximum contaminant levels allowed, based on the EPA National Secondary Drinking Water Regulations (40 CFR Part 143.3). Refer to section "18. Warranty" on page 68 for additional information.
If you suspect that your water is contaminated in any way, discontinue use of the water heater and contact an authorized technician or licensed professional.
If the incoming water is known to have a high mineral content or "hardness" (see warranty section), treatment is recommended upstream from the water heater.

iN401 - iN501 Preparation Before Installation

Dec 2022 - Revision 01

6. Gas Connection
WARNING
FIRE AND/OR EXPLOSION HAZARD To avoid serious injury or even death, the gas line installation and the gas line inlet pressure test must be done by a licensed professional.
Always match the water heater with the type of gas supplied to the unit (natural gas or propane). The water heater is factory preset for natural gas.
Make sure the gas line pressures are within normal limits. Pressures outside normal limits can result in poor performance and hazardous operating conditions.

6.2 Fuel Source
1. Natural gas is the factory preset.

6.1 Quick Reference Installation Instructions
1. Determine fuel source; natural gas or propane as shown in "6.2 Fuel Source" on page 14.
2. Measure gas pressure as shown in "6.3 Gas Pressure Requirements" on page 14.
3. Install a gas pressure regulator and vent line if gas pressure is above maximum recommendations as shown in "6.4 Gas Pressure Regulator" on page 14.
4. Measure the length of the supply line as shown in "6.5 Length of Gas Supply Line" on page 15".
5. Select the proper gas piping material as shown in "6.6 Gas Piping Material" on page 15.
6. Select the proper gas piping diameter as shown in "6.7 Determine Correct Gas Pipe Diameter" on page 15.
7. Install a drip leg on the gas piping as shown in "6.8 Gas Pipe Drip Leg and Shut-off Valve" on page 15.
8. Install a manual shut-off valve as shown in "6.8 Gas Pipe Drip Leg and Shut-off Valve" on page 15.
9. Test all gas line connections for leaks.
NOTICE
Do not fire (operate) the water heater until all connections have been completed and the heat engine is filled with water.

2. To convert the unit to propane, refer to the Propane (LPG) Conversion section in this manual.

6.3 Gas Pressure Requirements
iN series water heaters are designed to operate at gas pressures as low as 2.5" WC (at maximum firing rate). Gas inlet pressures to each unit should not exceed 14" WC under any condition (when unit is firing or not firing).

Natural Gas Static Gas Pressure

Parameters

Specifications

Minimum Static Gas Pressure

2.5" W.C. (non-corrugated, black iron)

Recommended Gas Pressure

8" W.C.

Maximum Static Gas Pressure

14" W.C.

6.4 Gas Pressure Regulator
1. If the gas inlet pressure is higher than recommended, install a gas pressure regulator to lower gas pressure to an acceptable level.
2. The gas pressure regulator must have the same or higher minimum to maximum modulation range as the model it is regulating. For example, an iN401 gas pressure regulator should have a modulation range of 30,000 BTU/h to 399,999 BTU/h.
3. Regulators should be mounted with a minimum of 12" of straight length pipe on either side and a recommended 6 ft from the appliance. If regulator manufacturer recommends more distance, then follow their guidelines.

iN401 - iN501 Gas Connection

May 2019 - Revision 00

4. When multiple units are connected use a dedicated gas pressure regulator for each unit.
5. To convert the unit to propane, refer to the Propane (LPG) Conversion section in this manual. For additional information refer to "11. Natural Gas to Propane Conversion" on page 34.
6.4.1 Venting of Gas Supply Regulators
Make sure the gas supply regulator is properly vented by following all local codes and the gas regulator manufacturer's recommendations.
1. The vent pipe must be at least the same size as the regulator vent.
2. When multiple units are connected, each regulator must have a separate vent line.
3. Vent lines must not be connected together or connected with any other appliance requiring external venting.
4. When selecting the size, the pipe diameter must be increased by one size for every 20 feet of pipe.
a. Each 90° elbow is equivalent to approximately: 4.5 feet for nominal pipe sizes of up to 1-1/2" 10.5 feet for nominal pipe sizes of up to 4".
b. Each 45° elbow is equivalent to approximately: 2 feet for nominal pipe sizes of up to 1-1/2" 5 feet for nominal pipe sizes of up to 4".
6.5 Length of Gas Supply Line
1. Make sure the length supply line is correctly sized.
a. Measure the length of the gas supply line from the gas meter to the water heater or other appliances requiring gas. The diameter of the pipe must be in relation to the length.
b. The total length of gas piping, as well as fitting pressure drop, must be considered when sizing the gas piping. Total equivalent length should be calculated from the meter or source location to the last heater connected.
c. Gas pipe size should be selected on the total equivalent length. The gas volume for cfh flow will be the input divided by the calorific value of the fuel to be supplied.
d. Use the Gas Pipe Sizing tables in this manual or refer to the gas line manufacturers sizing information to determine the correct diameter for the supply pipe.
e. The diameter of the gas lines, shown in the illustration, will vary according to the specific installation requirements.
6.6 Gas Piping Material
1. All gas piping and components must comply with NFPA local codes, and utility requirements minimum. Only gas approved fittings, valves, or pipe should be utilized.
2. Standard industry practice for gas piping is Schedule 40 iron pipe and fittings. All high and low gas pressure piping systems must comply with local utility and building codes.
3. Assembled piping should be clean of all scale, debris, metal particles, or foreign material.

4. The piping must be supported from the floor, ceiling, or walls and by the water heater itself.
6.7 Determine Correct Gas Pipe Diameter
Note: The water heater should be the first appliance to be connected to the gas supply line.
1. Determine the gas requirement of the water heater(s) and other appliances requiring gas.
2. Size the pipe diameter according to the COMBINED total maximum BTUH volume for all the appliances as if they were all operating at the same time. Use the "6.10 Gas Pipe Sizing Tables" on page 17.
3. Select the proper header pipe according to the number of units being connected together, as shown in the chart.

Header Sizing for Multiple iN Units

Number of Heaters

Sch 40 Iron

Pipe

4. The maximum pressure drop from the source to the final water heater must not exceed 0.3" W.C.
5. The maximum gas flow rate required is the sum of the maximum inputs of each unit divided by the heat of combustion of the fuel supplied at the location, (approximately 1,030 BTU per cubic foot for natural gas or 2,520 BTU per cubic foot for propane).
Note: The fuel supplier or utility should be consulted to confirm that sufficient volume and normal pressure is provided to the building at the discharge side of the gas meter or supply pipe.
6.8 Gas Pipe Drip Leg and Shut-off Valve
1. Install a gas pipe drip leg on each water heater to prevent dirt, condensation, or debris from entering the gas inlet.

Drip Leg
2. Local codes may require multiple units to have a full size drip leg on the main gas supply line and one on each unit.
3. The drip leg should have a removable clean-out cap. 4. The gas pipe must not be supported by the drip leg. 5. Following local building codes when selecting and installing
a shut-off valve.

iN401 - iN501 Gas Connection

Dec 2022 - Revision 01

6. Local codes may require multiple units to have a shut-off valve on the main gas supply line and one on each unit.
6.9 Connecting Gas Line to Unit
Note: Always clean the inside of the gas line of any dirt or debris before connecting the piping to the unit.
Main Supply Line

2. Install a manual shut-off valve as described in "6.8 Gas Pipe Drip Leg and Shut-off Valve" on page 15
Shut-off Valve

Manual Shut-off Valve

Drip Le g

Manual Shut-off
Va lve

Manual Shut-off Va lve
Drip Leg

Main Supply Line
Manual Shut-off Va lve

Drip Leg

Manual

Shut-off

Drip

Va lve

Leg

Drip Leg

1. Install a 4-5/8" OD flanged steel coupling and gasket with a short piece of 1-1/4" NPT black pipe.

Union
3. Install a drip leg in "6.8 Gas Pipe Drip Leg and Shut-off Valve" on page 15.
4. Continue installing pipe to reach the main gas supply connection.
5. Test all gas pipe connections. a. All the gas pipe connections should be tested as prescribed in NFPA 54. b. In multiple unit applications, each unit should be isolated before testing any piping system may exceed the allowable pressure of 14.0" W.C..
NOTICE
Do not fire (operate) the water heater until all connections have been completed and the heat engine is filled with water.

iN401 - iN501 Gas Connection

May 2019 - Revision 00

6.10 Gas Pipe Sizing Tables
This information is for reference only. Refer to gas pipe manufacturer specifications for actual delivery capacity. Contact the local gas supplier for actual BTU/ft3 rating. This data copied from the National Fire Protection Association Article 54 (NFPA 54).

Length including fittings (feet)

Pipe Sizes and BTU/h Capacity (NATURAL GAS). Use this table for static gas pressure LESS THAN 5" W.C.

3/4"

1-1/4"

1-1/2"

2-1/2"

360,000

678,000

1,390,000

2,090,000

4,020,000

6,400,000

11,300,000

247,000

466,000

957,000

1,430,000

2,760,000

4,400,000

7,780,000

199,000

374,000

768,000

1,150,000

2,220,000

3,530,000

6,250,000

320,000

657,000

985,000

1,900,000

3,020,000

5,350,000

284,000

583,000

873,000

1,680,000

2,680,000

4,740,000

257,000

528,000

791,000

1,520,000

2,430,000

4,290,000

237,000

486,000

728,000

1,400,000

2,230,000

3,950,000

220,000

452,000

677,000

1,300,000

2,080,000

3,670,000

207,000

424,000

635,000

1,220,000

1,950,000

3,450,000

100

400,000

600,000

1,160,000

1,840,000

3,260,000

125

355,000

532,000

1,020,000

1,630,000

2,890,000

150

322,000

482,000

928,000

1,480,000

2,610,000

175

296,000

443,000

854,000

1,360,000

2,410,000

200

275,000

412,000

794,000

1,270,000

2,240,000

Note: BTU/h capacities are based on specific gravity of 0.6, pressure drop of 0.5" WC

4"
23,100,000 15,900,000 12,700,000 10,900,000 9,660,000 8,760,000 8,050,000 7,490,000 7,030,000 6,640,000 5,890,000 5,330,000 4,910,000 4,560,000

Pipe Sizes and BTU/h Capacity (NATURAL GAS). Use this table for static gas pressure GREATER THAN 5" W.C.

Length

1/2"

3/4"

1-1/4"

1-1/2"

2-1/2"

including

fittings

(feet)

404,000

949,000

1,787,000

3,669,000 5,497,000 10,588,000 16,875,000 29,832,000 43,678,000

286,000

652,000

1,228,000

2,522,000 3,778,000 7,277,000

11,598,000 20,503,000 30,020,000

233,000

524,000

986,000

2,025,000 3,034,000 5,844,000 9,314,000

16,465,000 24,107,000

202,000

448,000

844,000

1,733,000

2,597,000 5,001,000 7,971,000

14,092,000 20,632,000

397,000

748,000

1,536,000

2,302,000 4,433,000

7,065,000

12,489,000 18,286,000

360,000

678,000

1,392,000

2,085,000 4,016,000

6,401,000

11,316,000 16,569,000

331,000

624,000

1,280,000

1,919,000

3,695,000 5,889,000 10,411,000 15,243,000

308,000

580,000

1,191,000

1,785,000

3,437,000

5,479,000

9,685,000 14,181,000

289,000

544,000

1,118,000

1,675,000

3,225,000

5,140,000

9,087,000

13,305,000

100

273,000

514,000

1,056,000 1,582,000 3,046,000 4,856,000 8,584,000 12,568,000

125

242,000

456,000

936,000

1,402,000 2,700,000 4,303,000 7,608,000 11,139,000

150

219,000

413,000

848,000

1,270,000

2,446,000 3,899,000 6,893,000

10,093,000

175

202,000

380,000

780,000

1,169,000

2,251,000 3,587,000 6,342,000 9,285,000

200

353,000

726,000

1,087,000

2,094,000 3,337,000

5,900,000 8,638,000

Note: For 1/2" line BTU/h capacities are based on specific gravity of 0.6, pressure drop of 4.6" WC and 5.0" WC. For all other line sizes, capacities are based on specific gravity of 0.6, pressure drop of 3.0" WC

iN401 - iN501 Gas Connection

Dec 2022 - Revision 01

Length including fittings (feet)

1/2"

Pipe sizes and BTU/h capacity (PROPANE). Use this table for static gas pressure GREATER THAN 5" W.C.

3/4"

1-1/4"

1-1/2"

2-1/2"

409,000

608,000

1,150,000

2,350,000 3,520,000 6,790,000 10,800,000

289,000

418,000

787,000

1,620,000 2,420,000 4,660,000 7,430,000

236,000

336,000

632,000

1,300,000 1,940,000 3,750,000 5,970,000

204,000

287,000

541,000

1,110,000

1,660,000

3,210,000

5,110,000

255,000

480,000

985,000

1,480,000 2,840,000 4,530,000

231,000

434,000

892,000

1,340,000 2,570,000 4,100,000

212,000

400,000

821,000

1,230,000 2,370,000 3,770,000

100

372,000

763,000

1,140,000

2,200,000 3,510,000

125

349,000

716,000

1,070,000

2,070,000 3,290,000

150

330,000

677,000

1,010,000

1,950,000 3,110,000

175

292,000

600,000

899,000

1,730,000

2,760,000

200

265,000

543,000

814,000

1,570,000

2,500,000

Note: The line BTU/h capacities are based on specific gravity of 1.5, pressure drop of 0.5" WC.

3"
19,100,000 13,100,000 10,600,000 9,030,000 8,000,000 7,250,000 6,670,000 6,210,000 5,820,000 5,500,000 4,880,000 4,420,000

4"
39,000,000 26,800,000 21,500,000 18,400,000 16,300,000 14,800,000 13,600,000 12,700,000 11,900,000 11,200,000 9,950,000 9,010,000

iN401 - iN501 Gas Connection

May 2019 - Revision 00

7. Air Intake Inlet and Exhaust Gas Outlet Pipe Connections

DANGER
Improper venting of the water heater will result in excessive levels of carbon monoxide, which can lead to severe personal injury or death. This water heater must be vented in accordance with the "Venting of Equipment" section of the latest edition of the ANSI Z223.1 / NFPA 54 (Natural Fuel Gas Code) in the USA, or in Canada refer to the "Venting Systems and Air Supply for Appliances" section in the latest version of CAN/CGA B149.1 (Natural Gas and Propane Installation Code), and all applicable local building codes. Vent installation should be performed only by a licensed professional.

3. Determine the straight line distance and the number of elbows required to route the air intake inlet and exhaust gas outlet pipes to their termination point. "7.6 Intake Air Inlet and Exhaust Gas Outlet Pipe Diameter and Length" on page 24.
4. Determine the diameter of pipe required to properly bring in intake air and vent exhaust gas. "7.6 Intake Air Inlet and Exhaust Gas Outlet Pipe Diameter and Length" on page 24.
5. Verify the location of the air intake inlet and exhaust gas outlet terminations are within state and local codes. "7.7 Venting Clearance Specifications" on page 25.
6. Select an approved material for the air intake inlet piping. "7.8 Exhaust Gas Outlet Pipe Materials" on page 26.

WARNING
BREAT H I N G H AZ ARD CARBON M ON OX I DE GAS
· Do not operate flood damaged water heaters.
· Install venting system according to the required codes and material manufacturers specifications.
· Do not obstruct fresh air intakes or exhaust outlets. Adequately support all vent system piping.
· Do not place vapor emitting products near water heater or air intake.
· Place working carbon monoxide detectors outside each sleeping area.
· Do not operate the water heater before properly installing the exhaust outlet.
· Visually inspect the vent system and eliminate any possible area where condensation could create a blockage of intake or exhaust air.
Breathing concentrated levels of carbon monoxide, even for a short period of time, will cause brain damage and can even lead to death.

7. Select an approved material for the exhaust gas outlet piping. "7.9 Air Intake Inlet Pipe Vent Materials" on page 26.
7.2 Typical Single Unit Air Intake Inlet and Exhaust Gas Outlet Pipe Installation
1. Select one of the two venting configurations: two pipes (direct vent) configuration or with one pipe (power vent) configuration.
2. Select the desired termination location and make sure each pipe terminates within all local and state codes.
3. Select the desired material for the air intake inlet and exhaust gas outlet pipes.
CAUTION
This water heater has a factory preset control to limit the exhaust gas temperature to 149°F (65°C) when the PVC is selected in the "Flue Type" programming section. As a result, the water heater can be vented with Schedule 40 PVC. If the incoming (or recirculation return) water temperature does not exceed 150°F (66°C), the exhaust gas temperature will not exceed 149°F (65°C).

Note: This water heater falls into the Category IV appliance. 7.1 Quick Reference Installation Guide 1. Select the desired type of venting system: Two Pipe Vent
System (Direct) or Single Pipe Vent System (Power).
"7.3 Two Pipe Vent System (Direct Vent)" on page 20.
"7.4 Single Pipe Venting System (Power Vent)" on page 22. 2. Select the desired termination of the air intake inlet and exhaust gas outlet pipe; outside wall or roof.

WARNING
When the unit is set for CPVC (polypropylene pipe), flue temperatures can reach 190°F (88°C). PVC pipe will melt at temperatures above 149°F (65°C) and could therefore result in a fire. Make sure the setting and the type of material being used for the flue are compatible.
For this application use Schedule 80 CPVC or Approved Polypropylene in the USA or Type BH Special Gas Vent Class IIB (CPCV) or Class IC (Polypropylene) that conforms to ULC-S636 in Canada.

"7.3.3 Side Wall Air Intake Inlet and Exhaust Gas Outlet Pipe Termination" on page 21.

"7.3.4 Roof Air Intake Inlet and Exhaust Gas Outlet Pipe Termination" on page 22.

19 iN401 - iN501 Air Intake Inlet and Exhaust Gas Outlet Pipe Connections Dec 2022 - Revision 01

SAFETY INSTRUCTIONS
On multiple unit installations, the air intake inlet and exhaust gas outlet piping from each water heater must be connected into the properly-sized common piping. Use the table in "7.6 Intake Air Inlet and Exhaust Gas Outlet Pipe Diameter and Length" on page 24 to determine the diameter of the common connecting piping between each individual water heater.

7.3 Two Pipe Vent System (Direct Vent)
7.3.1 Single Unit Configurations
The water heater can be directly vented without any modification using a 4 inch diameter pipe.
The following diagrams represent some typical direct venting configurations and are included to assist in designing the vent system. Possible configurations are not limited to the following diagrams.

4. Determine the length and corresponding diameter for the air inlet pipe and route the pipe to the desired termination location.
a. For termination of the pipe to the outside, continue installing the required pipe to a suitable outside location. Glue all connections, making sure the joints are sealed airtight.
b. Install suitable pipe support hangers every 4 to 5 feet, or as local building codes require.
IH-39

Exhaust
Intake Ai r

Exhaust

Intake Ai r

c. To configure the unit for power vent, insert a 3' section of 3" pipe.
5. Determine the length and corresponding diameter for the exhaust gas outlet pipe and route it to a suitable outside location.
a. Glue all connections, making sure the joints are sealed airtight.
b. Install all horizontal exhaust gas outlet piping with a minimum 2 degree (1/4" per foot) slope back toward the water heater. This allows any condensate that accumulates in the exhaust gas outlet pipe to properly drain back into the unit.
c. Install suitable pipe support hangers every 4 to 5 feet, or as local building codes require.
SAFETY INSTRUCTIONS
Do not connect any other appliance vents to the water heater inlet or outlet pipes.
6. If multiple units are installed, make sure the diameter of the connecting exhaust gas outlet pipe is properly sized for the number of units being installed.
iN401 - iN501 Air Intake Inlet and Exhaust Gas Outlet Pipe Connections 20 May 2019 - Revision 00

Exhaust
Intake Ai r

7.3.2 Multiple Units Configurations
When more than one unit is installed, refer to "7.6 Intake Air Inlet and Exhaust Gas Outlet Pipe Diameter and Length" on page 24.
Connecting multiple units together requires proper sizing of the air intake inlet and exhaust gas outlet pipes. Up to four water heaters can be connected (cascaded) together. Units which share a common vent must be connected together in a cascading configuration, as described in "13. Connecting Multiple Units" on page 47.
The following diagrams represent some typical direct venting configurations and are included to assist in designing the vent system. Possible configurations are not limited to the following diagrams.

7.3.3 Side Wall Air Intake Inlet and Exhaust Gas Outlet Pipe Termination
1. Terminate the air intake inlet pipe with a 90° elbow (angled down). Use a flange and PVC screen (not supplied).
2. Terminate the exhaust gas outlet pipe on the exterior wall at least 12" above ground and at least 18" away from the air intake inlet pipe, or as required by local building codes. In areas of high snow fall, protect the vent terminations from blockage. Use a flange and PVC guard.
1o8t"h-er3w6"iseis,ruesceo7m2m" oerngdreeda.ter.

Exhaust
Intake Ai r
Exhaust

Exhaust
IQ-020
Single unit.

Intake Air

s e e Note

Intake Ai r

Exhaust
Intake Ai r

Exhaust

IQ-020a

Intake Air

Multiple units.

Separation distance 0 - 17.9" 18" - 36"
36.1" - 71.9" 72" or greater

Allowed Not allowed
Allowed Not allowed
Allowed

3. To avoid moisture and frost build-up to openings on adjacent homes, use 45° elbows, 90° elbows, or tees for the vent termination to direct the exhaust gas fumes away from the building.

21 iN401 - iN501 Air Intake Inlet and Exhaust Gas Outlet Pipe Connections Dec 2022 - Revision 01

7.3.4 Roof Air Intake Inlet and Exhaust Gas Outlet Pipe Termination
Venting the unit through the roof is also an option. With this installation method, the terminations must extend at least 12" over maximum potential snow levels, or as required by local building codes. In areas of high snow fall, protect the vent terminations from blockage.
Terminate the air intake inlet pipe with a 90° elbow (angled down). A suitable roof flashing and vent cap (not supplied) should be installed.

12" USA or 18" Canada over maximum snow level or as required by local code
3' Minimum

12" Minimum

12" USA or 18" Canada over maximum snow level or as required by local code

7.4 Single Pipe Venting System (Power Vent) 7.4.1 Single Unit
The following illustrations represent some typical power venting configurations and are included to assist in designing the vent system. Possible configurations are not limited to these designs.
Intake Air
Exhaust
Intake Air

Single unit.

Exhaust

Intake Air

Exhaust

See Note A

Exhaust
Exhaust
Intake Air

Intake Air
Intake Air

Intake Air
Multiple units.
Note A: The distance between any exhaust gas outlet and air intake inlet pipe should be between 18 and 36 inches apart. If this minimum specification cannot be met, the air intake inlet and exhaust gas outlet pipes should be 72 inches apart or more.

Exhaust

Intake Air
Intake Air

iN401 - iN501 Air Intake Inlet and Exhaust Gas Outlet Pipe Connections 22 May 2019 - Revision 00

7.4.2 Multiple Units
When installing multiple units, refer to "7.6 Intake Air Inlet and Exhaust Gas Outlet Pipe Diameter and Length" on page 24.
Connecting multiple units together requires proper sizing of the air intake inlet and exhaust gas outlet pipes. Up to four water heaters can be connected (cascading) together. Units which share a common vent must be connected together in a cascading configuration, as described in "13. Connecting Multiple Units" on page 47.

Exhaust Exhaust

Intake Air
Intake Air

Intake Air
Intake Air
Exhaust

Intake Air
Intake Air
Decommisioined Air Intake and Gas Exhaust

23 iN401 - iN501 Air Intake Inlet and Exhaust Gas Outlet Pipe Connections Dec 2022 - Revision 01

7.5 Combustion Air Requirements
When using the single exhaust gas outlet pipe or power vent method, the following table outlines the required opening sizes for the combustion and ventilation air coming into the room and the required CFM requirements per water heater:

SAFETY INSTRUCTIONS
Do not operate the unit in an area that will draw in outside air contaminated with high levels of dust, sawdust, aerosols such as paint, or other airborne contaminants.
If necessary, purchase and install appropriate air screens and follow a regular cleaning program to ensure an adequate supply of clean, outside combustion air.

Required Combustion & Ventilation Air Opening Sizes (sq. in) Per Heater Per Boiler Room:

Model

Input

Air Type

Required CFM

Air is drawn directly from outside into the mechanical room

through two openings*, direct
or vertical

through one opening**

through two horizontal ducts

Air is drawn from another interior space inside the
building

Combustion Air

100

200

400

iN401

399,999

125

Ventilation Air

100

200

400

Combustion Air

125

250

500

iN501

499,999

125

Ventilation Air

125

250

500

*Where two openings are used, one must be within 12 inches of the floor and the other opening must be within 12 inches of the ceiling of the mechanical room. **Where one opening is required, it must be located within 12 inches of the ceiling.

7.6 Intake Air Inlet and Exhaust Gas Outlet Pipe Diameter and Length
The iN401 and iN501 come factory installed with 4 inch polypropylene (PP) venting. The following chart outlines the maximum length of venting allowable for each model.
A vent system's length is calculated by adding the length of all straight runs used (both horizontal and vertical) and then adding the equivalent lengths of each turn (90° or 45° elbow) used in the system.

SAFETY INSTRUCTIONS
A vent system's length must not exceed the maximum length outlined in the chart below.

Maximum Pipe Length in Feet

Number of Units
1

Venting Type
1 pipe 2 pipes

4" Diameter

iN401 250

iN501 180

125

Diameter, Model, and Length in Feet

6" Diameter

iN401

iN501

250

125

8" Diameter

iN401 250

iN501 250

125

1 pipe

2 pipes

250

125

1 pipe

2 pipes

250

176

250

125

1 pipe 4
2 pipes

250

125

1 pipe - Only exhaust out pipe is connected and the combustion air intake is from within the room. For example, one iN401 with a 4" diameter, the maximum exhaust pipe length for 1 pipe is 250 feet.

2 pipes - Both the Combustion air intake and the exhaust pipe are connected. In this case, the table specifies the maximum length per pipe. For example, one iN401 with 4" diameter, 125 feet maximum is allowed for combustion air intake pipe and exhaust out pipe. The 125 feet maximum is per pipe.

Note: 1. Reduce the maximum equivalent length above by 5 feet per 90° elbow used and by 2 feet per 45° elbow used. Do not exceed the above set limits.

2. If multiple units are common vented, then the units must be cascaded. Please refer to the combustion section for how to do combustion with common vented units.

iN401 - iN501 Air Intake Inlet and Exhaust Gas Outlet Pipe Connections 24 August 2021 - Revision 04

7.7 Venting Clearance Specifications

V V

V Operable Fixe d

Closed V

Fixed

Closed

Operable

IQ-010

Inside Corner Detail
X Air Inside Inlet

J A

V Vent Terminal

Area Where Terminal is Not Permitted

Gas Meter/Regulator

B
V L

Venting Clearance Specifications

Item A B C D E F G H

Description Clearances above grade, veranda, porch, deck, or balcony Clearances to window or door that may be opened Clearances to permanently closed window Vertical clearance to a ventilated soffit, eves, or overhang Clearances to unventilated soffit, eves, or overhang Clearances to outside corner Clearances to inside corner Clearances to each side of centerline extended from meter/regulator

Clearances to gas meter regulator vent outlet

Clearances to non-mechanical air supply inlet or combustion air inlet to any other appliance

Clearances to mechanical air supply inlet

Clearances to above paved sidewalk or paved driveway on public property

M Clearances under veranda, porch, deck, or balcony

*Per local/gas supplier codes. Use clearances in accordance with local building codes and local gas supplier. ** For single vent pipe/direct 4 feet (1.2 m) below or to the side of opening and 1 foot above opening.
1 In accordance with Z223.1 2 In accordance with CSA B149.1

Clearance Distance

USA1

Canada2

1 foot 1 foot**

1 foot 3 feet

3 feet within a height

15 feet above meter/

regulator assembly

3 feet

1 foot**

3 feet

3 feet above if within 10 feet horizontally
*

6 feet 7 feet

1 foot

Note: The vent for this appliance shall not terminate: Over public walkways; or Near soffit vents or crawl space vents or other areas where condensate or vapor could create a nuisance or hazard or cause property damage; or Where condensate vapor could cause damage or could be detrimental to the operation of regulators, relief valves, or other equipment.

25 iN401 - iN501 Air Intake Inlet and Exhaust Gas Outlet Pipe Connections Dec 2022 - Revision 01

7.8 Exhaust Gas Outlet Pipe Materials
SAFETY INSTRUCTIONS
For Canadian installations, plastic exhaust gas outlet piping must comply with CAN/CGA B149.1 and be certified to the Standard For Type BH Gas Venting Systems, ULC-S636. Components of this listed system must not be interchanged with other vent systems or unlisted pipes or fittings. All plastic components and specified primers and glues must be from a single system manufacturer and must not be intermixed with another system manufacturer's products.

If the inlet/return water temperature will exceed 150°F (66°C), do not use PVC pipe. Follow the display prompts to set the maximum water temperature for the exhaust gas outlet pipe material being used.

All units come factory installed with 4 inch polypropylene (PP) venting. A polypropylene to PVC adapter is included with each unit to enable the use of PVC exhaust gas outlet pipe. The maximum allowable venting distances are the same regardless of vent material selected.
The materials listed in the tables below outline the acceptable exhaust gas outlet pipe materials:

United States Exhaust Gas Outlet Pipe Standards

Material

Description*

Exhaust Gas
Outlet Pipe

PVC Schedule 40 (ASTM D1785) CPVC Schedule 80
Approved Polypropylene AL29-4C Stainless Steel

Canadian Exhaust Gas Outlet Pipe Standards

Material
Exhaust Gas
Outlet Pipe

Description (approved to ULC-S636)** Type BH Special Gas Vent Class IIA (PVC) Type BH Special Gas Vent Class IIB (CPVC) Type BH Special Gas Vent Class IIC (Polypropylene) Type BH Special Gas Vent Class I (AL29-4C Stainless
Steel)

*Note: Use of cellular core PVC (ASTM F891), cellular core CPVC, or Radel (polyphenylsulfone) in nonmetallic venting systems is prohibited. Covering non-metallic vent pipe and fittings with thermal insulation is prohibited.

**Note: The components (pipe, fittings, primers, and glues) must be from a single manufacturer; do not interchange. Follow the vent manufacturer's certified instructions.

SAFETY INSTRUCTIONS
Do not use cellular foam core pipe to vent exhaust gases.
This water heater has a built-in exhaust gas outlet temperature control that limits the exhaust gas temperature to a maximum of 149°F (65°C) for PVC pipe. In commercial applications which require higher water temperatures, exhaust gas temperature can reach 190°F (88°C) and require materials such as polypropylene (PP), stainless steel (SS), or CPVC.
If the temperature approaches the upper limit, the burner will turn off automatically to protect the vent pipe. Once the exhaust gas temperature has dropped to a normal operating level, the unit will automatically restart.

7.9 Air Intake Inlet Pipe Vent Materials
The air intake inlet pipe can be of any plastic or metal vent material available. ABS, PVC, polypropylene, galvanized steel, and/or flexible corrugated ducting are all examples. When using a corrugated material, ensure there is no inadvertent crimping or blockage to the air intake inlet pipe.
Refer to the table below for a list of approved materials.

Material Vent Pipe

United States Vent Pipe Standards
Description PVC Schedule 40 CPVC Schedule 80 Approved Polypropylene

Material Vent Pipe

Canadian Vent Pipe Standards Description
Type BH Special Gas Vent Class IIA (PVC) Type BH Special Gas Vent Class IIB (CPVC) Type BH Special Gas Vent Class IIC (Polypropylene)

Note: In addition to these charts, it is recommended to consult the most recent edition of ANSI Z223.1/NFPA 54 or CAN/CGA B149.1, as well as all applicable local codes and regulations when selecting vent pipe materials.

iN401 - iN501 Air Intake Inlet and Exhaust Gas Outlet Pipe Connections 26 May 2019 - Revision 00

7.10 Recommended Exhaust Gas Outlet Pipe Transitions
3X DIA. MIN 45°
Do not direct exhaust gas from opposite directions. Use a 45 degree transition, as shown.

1/4" Rise Per Foot Run Condensate Drain
1/4" Rise Per Foot Run Condensate Drain

Do not use reducers in a straight run of pipe.
Do not transition into a reducer or use a t-fitting. Transitions should always be directed into a straight run of pipe.

Do not use 90 degree transition into a reducer or a straight pipe.
27 iN401 - iN501 Air Intake Inlet and Exhaust Gas Outlet Pipe Connections Dec 2022 - Revision 01

8. Water Connections
Note: For flow rate changes faster than 10 gpm in one second, a water hammer arrester must be installed to prevent damage to the water heater.
8.1 Quick Reference Installation Instructions
1. Install the hot water pipe and the pressure relief valve (furnished with the water heater) as per "8.2 Hot Water Connection" on page 28.
NOTICE
When tightening any fittings to the connections on the water heater, care should be exercised not to overtighten these joints and damage the unit.
2. Install the cold water pipe as per "8.3 Cold Water Connection" on page 29.
3. Install a condensate drain line as per "8.4 Condensate Drain Line" on page 29.
4. After installation has been completed, fill and test the water heater for proper flow and inspect for leaks.
5. Run the hot water for a few minutes and then clean the inlet water strainer located on the cold water inlet fitting. This strainer must be cleaned periodically to maintain proper water flow.
8.2 Hot Water Connection
Install and connect the hot water lines. Keep the hot water pipes as short as possible to deliver hot water to the fixtures quickly. If an optional hot water storage tank is required, connect the hot water lines to this tank also.
Since each installation is different, it is up to the installer to route the water lines using the most efficient routing. The drawings shown here are only suggestions indicating the items needed for the installation.
CAUTION
To prevent adverse health issues, only materials (pipes, fittings, valves, solder, etc.) that are approved for use in potable water systems should be used.
1. Connect a 1-1/2" NPT coupler to the water heater's hot water connection.
2. Install a 1-1/2" union connection.
3. Install the supplied 3/4" 150 psi maximum pressure relief valve, into the port on the top of the unit.
4. Following local building codes, install a 1-1/2" manual shut-off valve with 1-1/2" NPT fittings.

WARNING
To prevent serious personal injury, do not install any shut-off device between the water heater and the pressure relief valve. This valve is designed to release abnormally high pressure within the water heater in the event of a system problem.
NOTICE
The pressure relief valve must be rated at 150 psi, the maximum btu/h output of the unit, and comply with all local building codes and standards. Do not install any restrictions or other valves prior to the pressure relief valve.
5. Install and route a discharge pipe from pressure relief valve to within six inches of the floor and directed away from walkways or other appliances.
a. Route the relief valve to within six inches of the floor to prevent injury in the event of a discharge.
b. The diameter of the pipe from the relief valve must be equal to the outlet size of the relief valve.
c. Do not use reducers in the outlet pipe.
d. Do not install any valves, restrictions, elbows, or other blockages in the outlet pipe.
e. For multiple unit installations, the outlet piping must not be connected together. Each pipe must be separately routed to a suitable drain.
6. Connect the unit to the building's hot water pipes. If multiple water heaters are being installed, the diameter of both the main cold water pipes and the main hot water pipes need to be sized by an engineering professional.
7. To conserve energy, insulate all hot water pipes and recirculation pipes.

iN401 - iN501 Water Connections

May 2019 - Revision 00

SAFETY INSTRUCTIONS
Do not insulate the pressure relief valve.
8. With the unit OFF, open a nearby hot water faucet and allow the water to flow through the unit until all the trapped air is exhausted from the water pipes and from the water heater.
9. Leak test the water piping. Repair any leaks immediately.
8.3 Cold Water Connection
Install and connect the cold water pipes.
Note 1: If the incoming water is known to have a high mineral content or "hardness" (see "18. Warranty" on page 68), treatment is recommended upstream from the water heater.
When the water heater is installed in a closed loop recirculation system, and if the cold water supply pipe has a back flow preventer, then an expansion tank should be installed to allow for water expansion as per the diagrams in "3.7 Configuration Options" on page 9.
CAUTION
To prevent adverse health issues, only materials (pipes, fittings, valves, solder, etc.) that are approved for use in potable water systems should be used.
1. Connect a 1-1/2" NPT coupler to the water heater's cold water connection.
2. Install a 1-1/2" union connection.

Note: Isolation valve kits can be used if incoming water treatment is anticipated (such as a water softener) due to hardness levels or heavy usage of the unit.
6. With the unit OFF, open a nearby cold water faucet and allow the water to flow through the unit until all the trapped air is exhausted from the water pipes and from the water heater.
7. Leak test the water pipes. Repair any leaks immediately.
8.4 Condensate Drain Line
Due to its efficient design, the water heater produces condensate (water) as a normal by-product of heating the water.
This condensate is acidic, with a pH level between 3 and 4. Local building codes may require an in-line neutralizer to be installed (not included) to treat this water. The maximum condensate flow rate is 3.6 GPH.
1. Install a 3/4" flexible hose to the hose connection on the water heater.
a. If a floor drain is used to remove the discharge, route the drain hose over or into the drain.
Note: Ensure that the flex tube is not pinched or kinked. The tube should freely drain. The tube termination should not be immersed in water.

Shut-off Valve
Union

Notes: Please check local plumbing code and install a condensate neutralizer if required.
2. Follow applicable local codes and if required, install in-line neutralizer to treat the acidic condensate. Follow all the installation instructions included with the neutralizer.

3. Following local building codes, install a 1-1/2" manual shut-off valve with 1-1/2" NPT fittings.
4. Connect the unit to the existing cold water pipes. 5. Connect the unit to the building's cold water pipes. If
multiple water heaters are being installed, the diameter of the main cold water pipe needs to be sized by an engineering professional.
29

iN401 - iN501 Water Connections May 2020 - Revision 02

9. Electrical Power
9.1 Electrical Recommendations

WARNING
To avoid serious injury or even death, follow all applicable local, state, and national regulations, mandates, and building codes for guidelines to install the electrical power supply.

Electrical code requirements are different in the USA and Canada. Refer to and follow the local building codes, the latest edition of the National Electrical Code (NFPA 70) in the USA, or the CGA C22.1 Canadian Electrical Code - Part 1.
For a single in401 or iN501 water heater, the circuit breaker(s) should be at least 15 amps per circuit. Please follow the local electrical code in determining the appropriate breaker size.
For multiple units install an adequately sized circuit breaker. Installing a separate circuit breaker for each unit is required to isolate units during service or repair.

15 (20) Amp Single Unit

15(20) Amp Unit#1
15(20) Amp Unit#2
15(20) Amp Unit#3
15(20) Amp Unit#4

WARNING
To avoid serious injury or even death from electrical hazards, an additional ON/OFF electrical junction box should be installed near the water heater. This switch will allow power to be removed from the water heater prior to service or in the case of an emergency.
3. Route a customer-supplied appropriately-sized, wire with ground from an electrical junction box with an ON/OFF switch through the back panel of the water heater. Route the wire through the cabinet to the junction box.
4. On the opposite side of the block from the factory installed wiring, connect the white wire to the white terminal, the black wire to the black terminal, and the green ground wire to the green terminal (for each circuit).

Note: For an electrical wiring schematic, refer to "15.2 Complete Wiring Diagram (all models)" on page 52 for additional information.

NOTICE
The electrical connections for the water heaters are polarity sensitive. Before connecting the water heater to the power source, test the polarity of the electrical circuit.
9.2 Connection Instructions
1. On single unit installations, make sure the electrical circuit being used is wired with appropriately sized wire (or at least 12 gauge) wire and grounded with an appropriately sized circuit breaker. Please note that the wire size varies based on the breaker size. The electrical power required for the water heater is 120V AC at 60 Hz.
2. Remove the two cover screws and open the cover.

5. If multiple units are being installed, install each with a dedicated, appropriately sized circuit breaker. For installing multiple units, refer to "13. Connecting Multiple Units" on page 47 for additional information.

iN401 - iN501 Electrical Power

Dec 2022 - Revision 01

10. Adjusting CO Level 2
10.1 General Information
This procedure is required:
1) only during installation in a high-altitude location over 8,000 feet, or
2) when converting the unit from natural gas to propane.
This procedure should be performed only by a qualified technician.

10.2 Adjustment Procedure
1. Open or remove the front doors.
2. Locate the gas valve on each heat engine. There are two heat engines.

DANGER

A concentration of carbon monoxide (CO) as small as 0.04% (400 parts per million) in the air can be fatal. When making High Fire and/or Low Fire adjustments, CO levels must be monitored using a flue gas analyzer and must not exceed 400 ppm of CO at any time during the operation.
Adjusting the "Low Fire screw" or the "High Fire screw" even in small increments can result in a significant increase in CO concentration. To avoid serious injury or death, DO NOT make any adjustments to the gas valve without monitoring the exhaust gases with a functional and calibrated flue gas analyzer.

Description
High Fire Low Fire
High Fire Low Fire

CO2 and CO Standards

CO Range (%) 2

Max. CO Level (ppm)

Natural Gas

9.1% to 9.3%

< 200 ppm

9.1% to 9.3%

< 60 ppm

Propane

10.1% to 10.5%

< 200 ppm

10.1% to 10.5%

< 60 ppm

3. Remove the plug from the test port on the exhaust manifold. Insert a calibrated flue gas analyzer into the test port.
4. Follow the display screens.

NOTICE
1. The values listed in the table are for nominal conditions. Variables such as gas pressure, heating value of the gas, humidity, and temperature of combustion air can impact CO and CO2 values. Changes in these variables can result in different CO and CO2 values on the same water heater.
2. A qualified service technician must use a calibrated flue gas analyzer to adjust the gas valve to achieve the desired CO2 and CO values.
3. Before any adjustments are made, the service technician must confirm the static gas pressure meets these minimum requirements. Natural Gas - 8" W.C. Propane - 11" W.C.
4. If units are cascaded and common vented, then combustion must be performed only one unit at any given time. Please valve off the hot water outlet of other units and power off them before performing combustion.

iN401 - iN501 Adjusting CO2 Level

August 2021 - Revision 04

9. If the CO2 values are within appropriate range, proceed to Step 10, otherwise continue.
a. Use a flat blade screwdriver to turn the High Fire screw clockwise to decrease and counterclockwise to increase the CO2 value.
b. Adjust in ¼ turn increments.
c. Wait three minutes to stabilize flue gas readings and recheck values.
d. Adjust until values fall with specified range.

NOTICE
Do NOT change the blower speed settings. This adjustment MUST be performed by factory personnel ONLY. Changing this setting WILL VOID the warranty!
5. Create a hot water flow of at least 6.0 GPM as shown on the display screen.

High FireScrew

10. Once the desired values are achieved, record the new High Fire CO2 "adjusted values" in the table.

Note: If flow rate is inadequate, a pop-up message will notify to increase the flow.

Description Natural Gas High Fire

CO and CO Standards 2 CO2 Range 9.1% to 9.3%

Propane High Fire

10.1% to 10.5%

Max. CO Level < 200 ppm < 200 ppm

Heat Engine (TOP)

CO 2

Value

Max CO ppm

Heat Engine (BOTTOM)

CO 2

Value

Max CO ppm

High Fire Recorded Values

Date ____ / ____ / _______

Initial Output

Adjusted Value

Initial Output

Adjusted Value

11. From the display screen, press Bottom Heat Engine and repeat the High Fire procedure for all heat engines.

6. At at a flow rate of 6.0 GPM, Top Heat Engine will start. 7. Allow three minutes of operation at High Fire. 8. Record "initial output" in Hire Fire Recorded Values table.

iN401 - iN501 Adjusting CO2 Level

May 2019 - Revision 00

12. Press LOW FIRE on the display screen.

13. Record "initial output" in Low Fire Recorded Values table.

Description Natural Gas Low Fire

CO2 and CO Standards CO2 Range
9.1% to 9.3%

Propane Low Fire

10.1% to 10.5%

Max. CO Level < 60 ppm < 60 ppm

Heat Engine (TOP)

CO 2

Value

Max CO ppm

Heat Engine (BOTTOM)

CO 2

Value

Max CO ppm

Low Fire Recorded Values

Date ____ / ____ / _______

Initial Output

Adjusted Value

Initial Output

Adjusted Value

17. When all heat engines have been properly adjusted, turn off water flow.
18. Remove the flue gas analyzer probe and plug the test port.
19. Press the back button to return to the main screen.
20.Check for gas leaks using a leak detector.
21. Install side panel covers. If converting to propane, proceed to section "11. Natural Gas to Propane Conversion" on page 34.

14. Adjust the Low Fire screw while the burner operates at low fire using a 2mm hex wrench. Turn clockwise to increase CO2 and counterclockwise to decrease CO2.

Low FireScrew

15. Once the desired values are achieved, record the new

Low

Fire

CO 2

"adjusted

values"

the

table.

16. From the display screen, press Bottom Heat Engine and repeat the Low Fire procedure for all heat engines.

iN401 - iN501 Adjusting CO2 Level Dec 2022 - Revision 01

11. Natural Gas to Propane Conversion
SAFETY INSTRUCTIONS
A qualified service technician MUST make the required changes to convert the water heater from Natural Gas to Propane.

b. Place the circuit breaker for the water heater at the main electrical panel in the OFF position. Verify there is no power to the unit(s).

11.1 General Information
Note: This conversion process also requires the CO2 levels to be adjusted. Refer to "11. Natural Gas to Propane Conversion" on page 34 for instructions.
Before converting the unit for propane, verify the current gas inlet pressure meets the recommended pressure and record it in the space below.

Propane Static Gas Pressure

Parameters Minimum Static Gas Pressure
Recommended Gas Pressure Maximum Static Gas Pressure

Specifications 8" W.C. (non-corrugated, black
iron) 11" W.C. 13" W.C.

Current Static Propane Gas Pressure ___________W.C. Date ___________________

tNoobtee:aTdjhuisstecdo.nvReerfseior ntop"ro10c.esAsdajulssotinrgeqCuOir2esLethveel"CoOn2

levels page

31 for instructions.

11.2 Conversion Procedure
1. Follow these steps before repositioning the DIP switches.

a. Turn the water heater OFF using the display screen.

c. Open the front door and locate the main circuit board. Note: There are two control boards in the iN401/iN501.
d. Locate DIP Switch 1 on each of the two circuit boards.

e. Move each DIP switch downward into the Propane position.

DIP Switch Settings (Réglages des commutateurs DIP)

SW1

ON
Propane

ON Natural Gas
(Gaz naturel)

iN401 - iN501 Natural Gas to Propane Conversion

May 2019 - Revision 00

f. Reset the circuit breaker to the ON position. Turn the water heater ON using the display screen.
2. Follow the display screens to check if the unit is now set to propane.
3. Refer to section "10. Adjusting CO2 Level" on page 31 in this manual for instructions to adjust CO levels.
2

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