TANKLESS EASY INSTALLATION GUIDE

Tips for Professional Installation & Product Setup

Image of a Rheem tankless water heater, a rectangular metallic appliance with a digital display showing '120' and control buttons.

REGISTER YOUR 15 YEAR WARRANTY

To register your product, scan the QR code located on the back cover. You will need your unit model and serial numbers to complete this process. These can be found on the label on the top panel inside of the tankless water heater.

All warranties void after 12,000 hours of operation.

NOTE: For Warranty Type, select "Standard" for all tankless products. The owner is required to provide proof of purchase/ownership at the time of the claim.

PRODUCT INFORMATION
MODEL:________________________
SERIAL #:________________________
INSTALL DATE:___________________
INSTALLER INFORMATION
NAME:__________________________
COMPANY:______________________
PHONE:_________________________

BEFORE YOU BEGIN

This guide is designed to provide a high-level installation overview and address key installation questions. It is not intended to replace the "Installation Instructions" in the Use & Care Manual provided with the water heater. All instructions and installation requirements as well as any local or national codes, must be followed.

It is recommended that this product be installed and serviced by a licensed plumber or a professional service technician. Rheem is not liable for any damages or defects resulting from improper installation.

? This icon will tell you which section of the use & care manual to check for more information

? This icon will point out helpful Installation tips

⚠️ This icon will point out information that is key to a safe installation.

A SUCCESSFUL INSTALL STARTS HERE

INSPECT SHIPMENT

FIND INSTALL LOCATION

Consider The Following:

Diagram showing minimum clearances: 0" (0 mm) from top, 12" (300 mm) from sides, 1/2" (13 mm) from bottom.

GATHER KEY ACCESSORIES (SOLD SEPARATELY)

Choosing a Location

Outdoor Conversion Kit (RTGH-X): This water heater can be converted from indoor model to outdoor model if following "Outdoor Conversion Instructions"

STEP 1: MOUNTING THE HEATER

Mounting

  1. Secure the mounting bracket to a support brace on the wall
  2. Lower the water heater onto the bracket plate. Bracket can slide from left to right for alignment.
  3. Secure the lower and upper bracket to the support brace on the wall to fix in place

Please see Use & Care Manual for more details on mounting locations.

STEP 2: WATER CONNECTION

Water Quality & Supply

  1. Connect cold and hot water at designated inlets
  2. Install service valves and a 150 psi rated pressure relief valve at hot water outlet.
  3. Water pressure of 65 psi (448 kPa) is required to achieve maximum flow rate

Use service valves for future service of the water heater. Expansion Tank required for installations using Recirculation.

STEP 3: GAS CONNECTION

Gas Supply

  1. Ensure that all gas connections, regulator(s), and meter are sized properly for the BTU/h rating. This unit is 1/2" gas line compatible (see Gas supply section of the Use & Care Manual)
  2. Install the gas shut-off valve directly on the gas supply connection on the bottom of the water heater
  3. Connect the gas piping to the valve
  4. Check all connections and fittings for leaks

⚠️ A properly sized and installed gas supply is critical to the proper operation of this water heater. Please see National and Local Fuel Gas Code for details.

CONDENSATION LINE

Condensate

External Condensate Neutralizer should be installed in accordance with local codes.

DRAIN

3/4" NPT MALE CONNECTION

COLD

HOT

GAS

STEP 4: VENTING

Venting

DIRECT VENT INSTALLATION

Compatible with Schedule 40 PVC, CPVC, and ABS venting (2" or 3"). (See Use and Care manual for complete list).

Diagram illustrating direct vent installation showing wall plate, air intake pipe, exhaust vent pipe, upward slope to termination, outside wall, condensate collector, condensate trap, power supply cord, hot water faucet connection, drain valve, relief valve, union, water filter, manual gas supply line, and service valve.

CONCENTRIC VENT TERMINATION

Diagram showing concentric vent termination with upward slope to termination, exhaust vent pipe, air intake pipe, inspection access panel (optional), ceiling.

FLAT VENT TERMINATION

Diagram showing flat vent termination with exhaust vent pipe, air intake pipe, upward slope to termination, inspection access panel (optional), ceiling.

It is recommended that the air intake pipe and exhaust pipe have a 1/4" per foot upward slope away from the unit.

When not using a termination kit, extend the exhaust a minimum of 12 inches further than the air intake to ensure clean air.

OUTDOOR INSTALLATION KIT

Typical Outdoor Water Heater (Outdoor Conversion Kit Required - sold separately)

Diagram of an outdoor water heater showing power supply cord, hot water faucet connection, condensate pipe, drain valve, built-in display, water filter, manual gas shut-off valve, manual gas supply line, union, sediment trap, service valve, cold water supply shut-off valve, cap, to suitable drain.

⚠️ 2" Venting may REQUIRE a DIP switch adjustment! See chart below for vent length and altitude settings.

⚠️ Please see Venting section of the Use & Care Manual for detailed venting requirements and proper clearances.

Number of 90° ElbowsSINGLE UNIT: MAX. EQUIVALENT VENT LENGTHS - STRAIGHT PIPE
Max Length 2" Straight PipeMax Length 3" Straight Pipe
060 ft. (18.3 m)150 ft. (45.7 m)
154 ft. (16.5 m)144 ft. (43.9 m)
248 ft. (14.6 m)138 ft. (42.7 m)
342 ft. (12.8 m)132 ft. (40.2 m)
436 ft. (11.0 m)126 ft. (38.4 m)
530 ft. (9.1 m)120 ft. (36.6 m)
624 ft. (7.3 m)114 ft. (34.7 m)
EQUIVALENT FT. OF ELBOWS
2" Pipe3" Pipe
90° 6 ft (1.83 m)6 ft (1.83 m)
45° 3 ft. (0.9 m)3 ft. (0.9 m)

STEP 5: ELECTRICAL

Electrical Wiring

  1. This water heater plugs into a standard 120VAC, 3-prong grounded outlet for indoor installation. Hard wiring is required for outdoor installation. Refer to "Outdoor Conversion Instructions" for outdoor installation.
  2. Do NOT connect this water heater to a GCFI or AFCI circuit.

This water heater draws 3 to 5 watts of current during standby, and up to 200 watts during the freeze protection operation.

Image of the water heater showing intake and exhaust ports.

START UP

Start Up

ENABLE (POWER ON): Press the power On/Off button

DISABLE (POWER OFF): Press the power On/Off button

SETTING THE TEMPERATURE

Press the ▲ or ▼ button to adjust temperature between 100-120°F.

To adjust set point above 120°F, press the ▲ button repeatedly until 120°F shows in the display.

Hold the ▲ button until the "120" on the display starts to blink.

Press and hold the ▲ button for 5 seconds to set above 120. Maximum set point is 140°F.

DIP SWITCH

Settings

2" Vent System Diameter
Identify Vent LengthIdentify Altitude
0 - 2,000 ft Dip2,001- 5,400 ft Dip5,400 - 7,800 ft Dip
MUST CHANGE FACTORY DIP SETTINGA-0 (Factory Setting)
DIP Switch Configuration: [Switches 1, 2, 3, 4 positions shown as ON, ON, ON, ON]
--
6 to 21 feet (1.8 to 6.4 meters)A-1
DIP Switch Configuration: [Switches 1, 2, 3, 4 positions shown as ON, ON, OFF, OFF]
B-1
DIP Switch Configuration: [Switches 1, 2, 3, 4 positions shown as ON, ON, OFF, OFF]
C-1
DIP Switch Configuration: [Switches 1, 2, 3, 4 positions shown as ON, ON, OFF, OFF]
21 to 42 feet (6.4 to 12.8 meters)A-2
DIP Switch Configuration: [Switches 1, 2, 3, 4 positions shown as ON, OFF, ON, OFF]
B-2
DIP Switch Configuration: [Switches 1, 2, 3, 4 positions shown as ON, OFF, ON, OFF]
C-2
DIP Switch Configuration: [Switches 1, 2, 3, 4 positions shown as ON, OFF, ON, OFF]
42 to 60 feet (12.8 to 18.3 meters)A-3
DIP Switch Configuration: [Switches 1, 2, 3, 4 positions shown as ON, OFF, OFF, ON]
B-3
DIP Switch Configuration: [Switches 1, 2, 3, 4 positions shown as ON, OFF, OFF, ON]
C-3
DIP Switch Configuration: [Switches 1, 2, 3, 4 positions shown as ON, OFF, OFF, ON]
3" Vent System Diameter
Identify Vent LengthIdentify Altitude
0 - 2,000 ft Dip2,001- 5,400 ft Dip5,400 - 7,800 ft Dip
6 to 45 feet (1.8 - 13.7 meters)A-0 (Factory Setting)
DIP Switch Configuration: [Switches 1, 2, 3, 4 positions shown as ON, ON, ON, ON]
B-0
DIP Switch Configuration: [Switches 1, 2, 3, 4 positions shown as ON, ON, ON, ON]
C-0
DIP Switch Configuration: [Switches 1, 2, 3, 4 positions shown as ON, ON, ON, ON]
45 to 150 feet (13.7 to 45.7 meters)A-1
DIP Switch Configuration: [Switches 1, 2, 3, 4 positions shown as ON, ON, OFF, OFF]
B-1
DIP Switch Configuration: [Switches 1, 2, 3, 4 positions shown as ON, ON, OFF, OFF]
C-1
DIP Switch Configuration: [Switches 1, 2, 3, 4 positions shown as ON, ON, OFF, OFF]

TROUBLESHOOTING

Error Codes / Troubleshooting

If a problem occurs, the unit will stop operating and display an error code. The most common error codes on start-up are:

Error CodePossible CauseSolution
11The gas shut-off valve is not fully opened.Check shut-off valve and open completely.
Gas service has been interrupted.Check gas supply.
12Low Gas SupplyContact a dealer or qualified service technician.
Check Dip Switch settings.Refer to Dip Switch chart.
29Condensation Trap is clogged.Contact a dealer or qualified service technician.
Air intake or vent exhaust opening may be blocked.Remove any blockage. (Air intake requires 12 in. [30 cm] of clearance.)
90The vent pipes on the vent termination may not be connected properly.Contact a dealer or qualified service technician.
P1Not enough water flow to operate the unit.Increase the water flow from the fixtures.

CLEARING ALARMS

  1. Turn off all hot water faucets.
  2. Turn off the water heater by pressing the Power ON/OFF button.
  3. Wait 5 minutes and then restart the water heater. Press the POWER ON/OFF button.
  4. Turn on a hot water faucet and check the display for errors.
  5. If the error remains, turn off the faucet and water heater. Unplug the water heater from power source. Wait 30 seconds and plug back in. Repeat steps 1 thru 4.
  6. If error code still remains, turn off faucet and water heater. Call for service assistance at the number listed in the Customer Service box below.

For all other codes not listed, please contact a dealer or qualified service technician.

CUSTOMER SERVICE/NEED HELP

HAVE QUESTIONS? NEED HELP TROUBLESHOOTING?

Get the unit's Model and Serial Numbers ready and contact us: US 1.800.432.8373 / Canada 1.800.268.6966

Be sure to have your Model and Serial Numbers before calling customer service (located on the water heater's Rating Label)

TIPS & MAINTENANCE

DRAINING THE WATER HEATER

⚠️ WARNING: IF THE BUILDING IS TO REMAIN UNOCCUPIED FOR AN EXTENDED PERIOD, IT IS RECOMMENDED THAT THE TANKLESS WATER HEATER BE DRAINED TO PREVENT POSSIBLE DAMAGE DUE TO FREEZING CONDITIONS.

Draining the Water Heater

FLUSHING THE UNIT

To ensure the best continued performance from your tankless water heater, we recommend cleaning your unit every year to year and a half. This process is called "flushing." Please refer to proper flushing procedures which can be found utilizing the QR code below.

To make this servicing even easier for you to remember, we've added a Maintenance Notification Setting to remind you that it is time to flush via a flashing code "88" on your tankless display or through the Econet® App on your phone (Wi-Fi Models Only).

SETTING SERVICE ALERT HOURS

  1. Press power button on the front control to turn off.
  2. Turn off the gas and water by closing the shut-off valves.
  3. Press and hold the ▲ or ▼ button until "1Y" is displayed.
  4. Press the ▲ or ▼ button until "8A " is displayed. Press and hold the power button on the display for 1 second.
  5. Press the ▲ or ▼ button to choose "50", "75", "100" or "OF".
DisplayedMaintenance Notice Hour
50500 hours
75750 hours
1001,000 hours
OFOFF

IF YOU HAVE A PROBLEM OR ISSUE WITH THIS WATER HEATER DO NOT RETURN, CALL FIRST.

Manufacturer National Service Department 1-866-720-2076

Models: 7D522B21 Tankless Water Heater, 7D522B21, Tankless Water Heater, Water Heater, Heater

File Info : application/pdf, 8 Pages, 3.67MB

PDF preview unavailable. Download the PDF instead.

1E135DF2-876A-4FF1-BBD1-E984A545C081 Adobe PDF Library 17.0 Adobe InDesign 18.0 (Macintosh)

Related Documents

Preview Rheem RTGH Series Super High Efficiency Condensing Tankless Water Heaters
Explore the Rheem RTGH Series Super High Efficiency Condensing Tankless Water Heaters, featuring advanced modern design, superior energy efficiency, flexible installation options, and smart Wi-Fi connectivity for optimal home comfort and environmental sustainability.
Preview Rheem RTGH Series High-Efficiency Condensing Tankless Gas Water Heaters | Specs & Features
Explore the Rheem RTGH Series Super High Efficiency Condensing Tankless Gas Water Heaters. Get detailed specifications, installation guides, flow rates, and accessories for models RTGH-68, RTGH-84, RTGH-90, and RTGH-95.
Preview Rheem ENERGY STAR 5.0 Certified Water Heaters
Discover Rheem's water heaters certified under the new ENERGY STAR 5.0 performance requirements, effective April 18, 2023. This guide details certified Heat Pump, High Efficiency Gas (Tankless, Storage), and Boiler models, highlighting eligibility for federal tax credits.
Preview Rheem Electric Tankless Series Water Heaters - Specifications and Applications
Comprehensive information on Rheem Electric Tankless Series water heaters, detailing features, applications, dimensions, electrical specifications, and flow rate performance for models RTE 3, RTE 7, RTE 9, RTE 13, RTE 18, and RTE 27.
Preview Rheem Professional Classic RTEX Tankless Electric Water Heaters: Specs & Sizing Guide
Explore the Rheem Professional Classic RTEX series tankless electric water heaters. Find detailed specifications, performance features, warranty information, and a comprehensive sizing guide for models RTEX-18, RTEX-24, RTEX-27, and RTEX-36.
Preview Rheem, Ruud, Richmond HVAC Price List - February 2023
Comprehensive price list for Rheem, Ruud, and Richmond HVAC products, including Hybrid Heat Pumps, Residential Tankless Gas Water Heaters, Commercial Tankless Gas Water Heaters, and Commercial Tankless Electric Water Heaters, effective February 1, 2023.
Preview Rheem Performance Platinum High Efficiency Condensing Tankless Gas Water Heaters
Discover the Rheem Performance Platinum™ series of high-efficiency condensing tankless gas water heaters, offering continuous hot water, advanced features, and eco-friendly operation for residential and commercial applications. Explore models ECOH200, ECOH180, and ECOH160 with EcoNet® WiFi capabilities.
Preview Rheem IKONIC Super High Efficiency Condensing Tankless Water Heater
Discover the Rheem IKONIC, the new standard in tankless water heating. This brochure details its super high efficiency, compact design, advanced features, and ease of installation, making it an ideal choice for modern homes.