Honeywell S8610U Universal Intermittent Pilot Module

SUPER TRADELINE®

INSTALLATION INSTRUCTIONS

APPLICATION

The SUPER TRADELINE® S8610U Universal Replacement Ignition Module is designed to provide easy field replacement of a wide range of intermittent pilot ignition modules manufactured by Honeywell, Robertshaw, Penn-Johnson and others. The S8610U module provides ignition sequence, flame monitoring, and safety shutoff for intermittent pilot central furnaces, residential boilers, and other heating appliances. The S8610U replaces existing flame rectification type intermittent pilot ignition modules with the following characteristics:

• Single rod (local sense) or two rod (remote sense) flame sensing.
• Non-100 percent shutoff, 100 percent shutoff/lockout, or 100 percent shutoff/continuous retry.
• Natural or LP gas.
• Shutoff/lockout times of 30 seconds or longer.
• Prepurge times of four seconds or shorter.
• Pilot burners with flow rates of 1500 Btuh or less.
• With or without vent dampers.

▲ WARNING

Check Table 1 before replacing an existing intermittent pilot module with the S8610U. If the existing module is not listed, do not use the S8610U to replace it unless you are certain the specifications of the S8610U match those of the existing module.

A complete list of the specific Honeywell and other modules that the SUPER TRADELINE® S8610U is designed to replace is provided in Table 1.

The S8610U SUPER TRADELINE® package contains complete, easy-to-use instructions, plus the accessories required to adapt the existing spark cable (Rajah, stud, nail, or other) to the spark terminal on the S8610U. It also provides labels to help assure proper marking of the wires attached to the existing module.

INSTALLATION INSTRUCTIONS

The S8610U SUPER TRADELINE® Universal Module is not designed to replace controls with the following characteristics:

• Flame sensing other than by flame rectification (White Rodgers Cycle-Pilot®, or Robertshaw thermal sensing).
• Flame rectification modules with shutoff/lockout times of less than 30 seconds, prepurge times of more than 4 seconds, or pilot burners larger than 1500 Btuh.
• Standing pilot appliances.

Honeywell provides additional control packages to accomplish these replacements. See the Honeywell Electronic Ignition Service Manual, form 70-6604, or call your Honeywell wholesaler.

SPECIFICATIONS

Electrical Ratings: Voltage: 24V, 60 Hz. Current Draw: 1A pilot valve, 2A main valve. Valve Contact Rating: 0.2A.

Trial For Ignition: 90 seconds maximum, then 100 percent shutoff (pilot and main gas).

Continuous Retry: Five-minute minimum (six-minute nominal) delay if pilot fails to light during trial for ignition. After delay, trial for ignition is repeated. This sequence (trial, delay, trial, delay) continues until pilot lights or call for heat ends.

Flame Failure Response Time: 0.8 sec max at 1.0 uA flame current.

Ambient Operating Temperature: -40°F to 165°F (-40°C to 74°C). (If main valve current is 1A or less, 175°F (79°C) maximum ambient applies.)

Table 1. S8610U Replaces these Ignition Modules.

PLANNING THE INSTALLATION

▲ WARNING

FIRE OR EXPLOSION HAZARD CAN CAUSE PROPERTY DAMAGE, SEVERE INJURY, OR DEATH.

Follow these warnings exactly:

1. Plan the installation as outlined below.
2. Plan for frequent maintenance as described in the Maintenance section.

When intermittent pilot systems are used on central heating equipment in barns, greenhouses, and commercial properties and on heating appliances such as commercial cookers, agricultural equipment, industrial heating equipment and pool heaters, heavy demands are made on the controls. Special steps can be required to prevent nuisance shutdowns and control failure due to frequent cycling, severe environmental conditions related to moisture, corrosive chemicals, dust or excessive heat. These applications require Honeywell Home and Building Control Engineering review; contact your Honeywell Sales Representative for assistance.

Review the following conditions that can apply to your specific installation and take the precautionary steps suggested.

Frequent Cycling

These controls are designed for use on appliances that typically cycle three to four times an hour only during the heating season. In year-round applications with greater cycling rates, the control can wear out more quickly; perform a monthly checkout.

Water or Steam Cleaning

If a module or gas control gets wet, replace it. If the appliance is likely to be cleaned with water or steam, protect (cover) the controls and wiring from water or steam flow. Mount the controls high enough above the bottom of the cabinet so they do not get wet during normal cleaning procedures. Use a NEMA 4 enclosure for the ignition module; see the Electronic Ignition Service Manual, form 70-6604.

High Humidity or Dripping Water

Dripping water can cause the module to fail. Never install an appliance where water can drip on the controls. In addition, high ambient humidity can cause the gas control to corrode and fail.

If the appliance is in a humid atmosphere, make sure air circulation around the controls is adequate to prevent condensation. Also, regularly check out the system. A NEMA 4 enclosure is recommended for the ignition module; see the Electronic Ignition Service Manual, form 70-6604.

Corrosive Chemicals

Corrosive chemicals can attack the module and gas control, eventually causing a failure. If chemicals are used for routine cleaning, make sure they do not reach the controls. Where chemicals are suspended in air, as in some industrial or agricultural applications, use a NEMA 4 enclosure for the ignition module; see the Electronic Ignition Service Manual, form 70-6604.

Dust or Grease Accumulation

Heavy accumulations of dust or grease can cause controls to malfunction. Where dust or grease can be a problem, provide covers for the module and the gas control to limit contamination. A NEMA 4 enclosure is recommended for the ignition module; see the Electronic Ignition Service Manual, form 70-6604.

Heat

Excessively high temperatures can damage controls. Make sure the maximum ambient temperature at the control does not exceed the rating of the control. If the appliance operates at very high temperatures, use insulation, shielding, and air circulation, as necessary, to protect the controls. Proper insulation or shielding should be provided by the appliance manufacturer; verify proper air circulation is maintained when the appliance is installed.

INSTALLATION

When Installing this Ignition System...

1. Read these instructions carefully. Failure to follow them could damage the components or cause a hazardous condition.
2. Check the ratings given in the instructions and on the components to make sure they are suitable for your application.
3. Installer must be a trained, experienced service technician.
4. After installation is complete, check out component operation as provided in these instructions.

▲ WARNING

FIRE OR EXPLOSION HAZARD CAN CAUSE PROPERTY DAMAGE, SEVERE INJURY, OR DEATH.

1. If the ignition module gets wet, it can malfunction, leading to the accumulation of explosive gas.
   • Never install where water can flood, drip or condense on the module.
   • Never use a module that has been wet. Replace it.
2. Liquefied petroleum (LP) gas is heavier than air and will not vent upward naturally.
   • Do not light the pilot or operate electric switches, lights or appliances until you are sure the appliance area is free of gas.
3. Do not attempt to disassemble or clean the module. Improper reassembly and cleaning can cause unreliable operation.

! CAUTION

1. Disconnect power supply before beginning wiring to prevent electrical shock or equipment damage.
2. If a new gas control is to be installed, turn off the gas supply before starting installation. Conduct a Gas Leak Test according to the gas control manufacturer instructions after the gas control is installed.
3. If the module must be mounted near moisture or water, provide a suitable waterproof enclosure.
4. Using the wire labels provided, label all wires before they are disconnected. Wiring errors can cause improper appliance operation and dangerous conditions such as bypassing safety features.

Perform Preinstallation Safety Inspection

The preinstallation checks described in ANSI Standard Z21.71 in Exhibit A must be done before the replacement module is installed. If a condition that could result in unsafe operation is detected, the appliance should be shut off and the owner advised of the unsafe condition. Correct any potentially unsafe condition before proceeding with the installation.

Remove Old Module

Disconnect power supply before doing any work on the unit. Disconnect and tag the wires from the old module using the wire labels provided. Remove the old module from its mounting location.

Mount New Ignition Module

We recommend mounting the S8610U Module in the same location as the old module, if possible. Otherwise, select a location close enough to the burner to allow a short (3 ft. (0.9 m) maximum), direct cable route to the igniter. Ambient temperature at the module must be within the range listed in the Application section.

Mount the module with the terminals down to protect them from dripping water and dust. The module can also be mounted with the terminals on either side. Do not mount with the terminals pointing up. Refer to Fig. 1 for mounting recommendations. When it is necessary to drill new mounting holes, use the S8610U as a template to mark mounting hole pattern. Drill new holes, as required. Fasten securely with four No. 6-32 machine or No. 8 sheetmetal screws.

Fig. 1. Module mounting recommendations: Shows modules mounted with terminals facing down, left, or right. It explicitly states DO NOT MOUNT WITH TERMINALS FACING UP.

Wire the Module

CAUTION

1. Check the wiring diagram furnished by the appliance manufacturer, if available, and compare with Tables 3 through 6. Carefully follow any special instructions affecting the general wiring procedures outlined below.
2. Disconnect the power supply before making wiring connections to prevent electrical shock or equipment damage.

IMPORTANT

1. A common ground is required on:
   • The pilot burner mounting bracket, and
   • The GND (BURNER) terminal on the ignition module. Failure to use the GND (BURNER) terminal can result in intermittent loss of spark and/or loss of flame current sensitivity.
2. Make sure the transformer has adequate VA. The ignition module requires at least 0.2A at 24 Vac. Add the current draws of all other devices in the control circuit, including the pilot and main valves in the gas control, and multiply by 24 to determine the total VA requirement of these components. Add this total to 4.8 VA (for the ignition module). The result is the minimum transformer VA rating. Use a Class II transformer when replacement is required.
3. When a vent damper is connected to the S8610U vent damper connector, be sure the system transformer delivers at least 30 VA. The S8610U has an internal fuse that is intended to prevent appliance lightoff if the vent damper is not in place or wired properly. Using a small transformer can interfere with the proper operation of the fuse and bypass the intended safety feature.

Connect the wires to the S8610U Ignition Module as shown in Tables 3 through 6. Make sure that adequate system ground is provided as indicated in the wiring tables.

Verify the thermostat anticipator setting as explained in the Important.

NOTE: The wiring diagrams in Fig. 2 through 4 show typical hookups with the S8610U Ignition Module and should be used for reference only.

Modify Ignition Cable, If Necessary

Use existing ignition cable if it is in good condition. If the existing ignition cable does not have a 1/4 in. quick-connect on the module end, either use the Rajah adapter or strip the wire and replace with the 1/4 in. insulated quick-connect supplied. If the cable must be replaced, order a Honeywell ignition cable, see Table 2. It might be necessary to replace the connector at the pilot burner end to match the pilot burner spark termination.

NOTE: When using an S8610U to replace an S86, use the enclosed adapter to convert the S86 Ignition Cable to an S8610U Ignition Cable. Then, install the adapter and cable to the S8610U Ignition Module.

Table 2. Honeywell Preassembled Ignition Cables (UL Style 3257).

Table 3. Conversion from Honeywell S86, S90, S8600 and S8610 to S8610U1003.

a If 25V (2) and TH-R have wires connected, disconnect and splice together with solderless connector.

b If TH-R and TH-W are jumpered together, connect 25V (2) lead from S86 to TH-W on S8610U1003.

c Use Rajah to quick connector adapter (supplied) or cut Rajah connector off ignition cable at module end; attach insulated quick connect for connection to S8610.

d Leave black jumper connected.

e Terminals may be marked 25V on some models and 24V on later models. These are functionally equivalent.

f On dual igniter and sensor models, remove jumper quick connect from S8610U1003 Sense terminal, cut jumper wire at circuit board, and discard.

Table 4. Conversion from Robertshaw SP715 and SP735C to S8610U1003 (Includes 780-XXX and USI715U).

1. Use existing wiring harness to make connections to S8610 per table. IMPORTANT: If installation includes LO-15 Lockout Timer, discard wires to E3 and TH. Disconnect and retain wire to LO-15 terminal E1. Tag wire, Thermostat. Discard LO-15.

2. On 7000D series valve, retain (or install) white jumper between valve TR and pilot solenoid.

a If LO-15 Lockout timer is not installed, E3 connector provided on SP715 is not used.

b Important: If the USI 715U with combination igniter sensor is not used, remove black jumper quick connect from Sense terminal of S8610U1003. Cut jumper wire at circuit board and discard.

c For replacement of Robertshaw Flame Switch systems (SP710, 720, 730, 750, 780-700, 780-701, 780-710, 780-711, 780-712 and 780-713), see Honeywell Ignition Control Handbook.

d 780-715 and USI 715U are equivalent to SP715; 780-735 and 780-737 are equivalent to SP735. For other 780-XXX models, see notec.

e OPT. SENSOR on USI 715U. No external connection if combination igniter sensor is used.

Table 5. Conversion from Penn-Johnson CSA--(All), G60, G65, G66, G67, G600, G670 Or G770 to S8610U1003.

a Discard wire between transformer and terminal 5 (G60) or 6 (G600); otherwise, use existing harness for wiring.

b Discard wires between Y79A and module as follows: Red to 3, Black to 2, White to GR. Discard wire between transformer and 6.

c Discard wires between Y79B and module as follows: White to 3, Black to 1, Brown to GR. Discard wire between transformer and 6.

d CSA code numbers (for example, CSA45A-600R) are equivalent to G600 and use the same wiring information tables.

e Important: Remove black jumper quick connect from Sense terminal of S8610U1003; cut jumper wire at circuit board and discard.

*IF INSTALLATION DOES NOT INCLUDE VENT DAMPER WITH PLUG CONNECTION TO MODULE:

1. Leave vent damper plug on S8610U Module in position.
2. Use TH-W terminal.

*IF INSTALLATION INCLUDES VENT DAMPER WITH PLUG CONNECTION TO MODULE:

1. Replace S8610U Module vent damper plug with damper Molex connector.
2. Wire thermostat W wire to TH-W.
3. Run wire from switched leg of transformer secondary to both thermostat R and S8610 Module 24V terminals.

Table 6. Conversion from Camstat, Fenwal or HSC to S8610U1003.

a Use existing wiring harness to make connections to S8610.

b Tag all wires at module connector with terminal designations. Cut wires at connector, attach quick connects and connect to S8610; per table.

c Important: Remove black jumper quick connect from Sense terminal of S8610U1003; cut jumper wire at circuit board and discard.

Wiring Diagrams

Fig. 2. S8610U in heating system with atmospheric burner. This diagram illustrates the typical wiring connections for the S8610U module in an atmospheric burner system. It shows connections to the thermostat, limit controller, vent damper plug, dual valve combination gas control (pilot and main valve operators), igniter, and sensor. Key terminals on the S8610U include GND (BURNER), MV, MV/PV, PV, 24V GND, TH-W, SENSE, and SPARK. It includes warnings regarding power supply, alternate limit controller locations, maximum cable length, 24V circuit grounding, vent damper plug usage, and minimum VA for vent damper connections.

Fig. 3. S8610U in heating system with power-assisted combustion. This diagram shows the wiring for the S8610U module in a power-assisted combustion system. It includes connections to the thermostat, limit controller, vent damper plug, dual valve combination gas control, igniter, sensor, combustion air blower relay, and combustion air blower motor. Similar warnings as in Fig. 2 are present, emphasizing power supply, grounding, and vent damper connections.

Operation Sequence

Fig. 4. S8610U in typical ST9120 application. This flowchart outlines the operational sequence:

1. START
2. STAGE 1: TRIAL FOR IGNITION
   • Thermostat (Controller) calls for heat.
   • Spark generator powered; first valve (pilot) operator opens.
   • Pilot burner lights. Module senses flame current.
3. STAGE 2: MAIN BURNER OPERATION
   • FLAME CURRENT SENSED: Spark generator off; second valve operator (main) opens.
   • Module monitors pilot flame current.
4. END

The flowchart also details specific conditions:

• PILOT BURNER OPERATION: If pilot fails to light within 90 seconds, the system shuts off. After a minimum 5-minute delay, the trial for ignition restarts. This cycle repeats until the pilot lights or the call for heat ends.
• POWER INTERRUPTION: System shuts off and restarts when power is restored.
• PILOT FLAME FAILURE: Main valve closes, and the module starts a trial for ignition.
• THERMOSTAT (CONTROLLER) SATISFIED: Valves close, pilot and main burners turn off.

STARTUP AND CHECKOUT

Check out the gas control system:

• At initial installation of the appliance.
• As part of regular maintenance procedures.
• At maintenance intervals determined by the application.
• As the first step in troubleshooting.
• Any time work is done on the system.

Maintenance frequency must be determined individually for each application; see Maintenance section.

▲ WARNING

FIRE OR EXPLOSION HAZARD CAN CAUSE PROPERTY DAMAGE, SEVERE INJURY, OR DEATH.

1. If you smell gas or suspect a gas leak, turn off the gas at the manual service valve and evacuate the building. Do not try to light any appliance; do not touch any electrical switch or telephone in the building until you are sure no spilled gas remains.
2. Gas leak test must be done as described in Steps 1 and 6 below during initial installation and anytime work is done involving the gas piping.

Step 1: Perform visual inspection.

1. With power off, make sure all wiring connections are clean and tight.
2. Turn on the power to the appliance.
3. Open the manual shutoff valves in the gas line to the appliance.
4. Test for gas leak before gas control if piping has been disturbed.

Gas Leak Test: Paint the gas control gasket edges and all pipe connections downstream of the gas control, including the pilot tubing connections, with a rich soap and water solution. Bubbles indicate gas leaks. Tighten the joints and screws or replace component to stop gas leak. Recheck with soap and water solution.

Step 2: Verify control system ground.

The igniter, flame sensor, and ignition module must share a common ground with the main burner. Use thermoplastic insulated wire with a minimum rating of 105°C (221°F) for the ground wire; asbestos insulation is not acceptable. If the temperature at the wire could exceed 105°C (221°F), use a shield to protect the wire from radiant heat generated by the burner. Connect the ground wire as follows:

1. Fit one end of the ground wire with a female 1/4 in. quick-connect terminal and connect it to the male quick-connect GND (BURNER) terminal on the ignition module.
2. Strip the other end of the wire and fasten it under the igniter bracket mounting screw. If necessary, use a shield to protect the ground wire from radiant heat.
3. The burner serves as the common grounding area. If there is not good metal-to-metal contact between the burner and ground, run a lead from the burner to ground.

NOTE: Earth ground is not required.

Step 3: Review normal operating sequence and module specifications.

See Operation and Application sections.

Step 4: Reset the module.

1. Turn the thermostat to its lowest setting.
2. Wait one minute.

As you do Steps 4 and 5, watch for points where operation deviates from normal. Refer to Troubleshooting Guide, Fig. 7, to correct problem.

Step 5: Check safety shutoff operation.

1. Turn off the gas supply.
2. Set the thermostat or controller above the room temperature to call for heat.
3. Watch for spark at pilot burner.
4. Time spark from start to shutoff. Spark should shut off after 90 seconds maximum. Ignition sequence repeats after five minutes minimum.
5. Open manual gas control knob and make sure no gas is flowing to pilot or main burner.
6. Set the thermostat below the room temperature and wait one minute before continuing.

Step 6: Check normal operation.

1. Set the thermostat or controller above the room temperature to call for heat.
2. Make sure the pilot lights smoothly when the gas reaches the pilot burner.
3. Make sure the main burner lights smoothly without flashback.
4. Make sure the burner operates smoothly without floating, lifting, or flame rollout to the furnace vestibule or heat buildup in the vestibule.
5. If the gas line has been disturbed, complete the gas leak test.

Gas Leak Test: Paint the gas control gasket edges and all pipe connections downstream of the gas control, including pilot tubing connections, with a rich soap and water solution. Bubbles indicate gas leaks. Tighten the joints and screws or replace component to stop gas leak. Recheck with soap and water solution.

1. Turn the thermostat or controller below the room temperature. Make sure the main burner and pilot flames go out.

MAINTENANCE

▲ WARNING

FIRE OR EXPLOSION HAZARD CAN CAUSE PROPERTY DAMAGE, SEVERE INJURY, OR DEATH. Do not attempt to take the module apart or to clean it. Improper assembly and cleaning can cause unreliable operation.

Regular preventive maintenance is important in applications that place a heavy load on system controls, such as in the commercial cooking and agricultural and industrial industries because:

• In many applications, particularly commercial cooking, the equipment operates 100,000 to 200,000 cycles per year. Such heavy cycling can wear out the gas control in one to two years.
• Exposure to water, dirt, chemicals and heat can damage the gas control and shut down the control system. A NEMA 4 enclosure can reduce exposure to environmental contaminants. See electronic Ignition Service Manual, form 70-6604.

The maintenance program should include regular system checkout as outlined in the Startup and Checkout section, and the control system as described in the appliance manufacturer literature.

Maintenance frequency must be determined individually for each application. Some considerations are:

• Cycling frequency. Appliances that can cycle 20,000 times annually should be checked monthly.
• Intermittent use. Appliances that are used seasonally should be checked before shutdown and again before the next use.
• Consequence of unexpected shutdown. Where the cost of an unexpected shutdown would be high, the system should be checked more often.
• Dusty, wet, or corrosive environment. Because these environments can cause the gas control to deteriorate more rapidly, the system should be checked more often.

Any control should be replaced if it does not perform properly on checkout or troubleshooting. In addition, replace any module if it is wet or looks like it has ever been wet. Protective enclosures, as described in Planning the Installation section, are recommended regardless of checkout frequency.

Troubleshooting Guide

Fig. 5. S8610U normal operating sequence. This flowchart guides troubleshooting:

1. START
2. Turn off gas supply. Turn thermostat (controller) to call for heat.
3. Check power to module (24V nominal) at TH-W and 24V terminals.
4. If vent damper is connected, check line voltage, transformer, limit controller, thermostat, and air proving switch. Verify vent damper is open.
5. If spark is not across igniter/sensor gap:
   • Pull ignition lead and check spark at module.
   • If spark is not okay:
     • Check vent damper plug status (if applicable); replace vent damper if necessary.
     • On other models, replace module.
   • If spark is okay:
     • Check ignition cable, ground wiring, ceramic insulator, and gap.
     • Check ignition cable boot for melting/buckling; replace and shield if necessary.
6. Turn on gas supply.
7. If pilot burner does not light:
   • Check manual gas valves, tubing, pressures, and pilot burner orifice.
   • Check electrical connections to module and pilot operator.
   • Check for 24 Vac across PV-MV/PV terminals. Replace gas control if voltage is okay, otherwise replace module.
8. If spark stops when pilot is lit:
   • Check continuity of ignition cable and ground wire.
   • Clean flame rod.
   • Check electrical connections to flame rod and module.
   • Check for cracked ceramic flame rod insulator.
   • Check pilot flame is steady, blue, and covers flame rod. Adjust pilot flame if necessary.
   • If problem persists, replace module.
9. If main burner does not light:
   • Check for 24 Vac across MV-MV/PV terminals. Replace module if no voltage.
   • Check electrical connections to module and gas control. Replace gas control or operator if okay.
   • Check continuity of ignition cable and ground wire.
   • Check temperature at igniter-sensor insulator.
   • Check pilot flame covers flame rod.
   • If checks are okay, replace module.
10. If system runs until call for heat ends:
    • Check for proper thermostat operation.
    • Remove MV lead; if valve closes, check controller/wiring. If not, replace gas control.
11. If call for heat ends and system shuts off:
    • Repeat procedure until troublefree operation is obtained.

Ignition System Checks

Step 1: Check ignition cable.

Make sure:

1. Ignition cable does not run in contact with any metal surfaces.
2. Ignition cable is no more than 36 in. (0.9m) long.
3. Connections to the ignition module and to the igniter or igniter-sensor are clean and tight.
4. Ignition cable provides good electrical continuity.

Step 2: Check ignition system grounding. Nuisance shutdowns are often caused by a poor or erratic ground.

1. A common ground, usually supplied by the pilot burner bracket, is required for the module and the pilot burner/igniter-sensor.
   • Check for good metal-to-metal contact between the pilot burner bracket and the main burner.
   • Check the ground lead from the GND (BURNER) terminal on the module to the pilot burner. Make sure connections are clean and tight. If the wire is damaged or deteriorated, replace it with No. 14 through 18 gauge, moisture-resistant, thermoplastic insulated wire with 105°C (221°F) minimum rating.
   • Check the ceramic flame rod insulator for cracks or evidence of exposure to extreme heat, which can permit leakage to ground. Replace pilot burner/igniter-sensor and provide shield, if necessary.
   • If flame rod or bracket are bent out of position, restore to correct position.

Step 3: Check spark ignition circuit. You will need a short jumper wire made from ignition cable or other heavily insulated wire.

1. Close the manual gas valve.
2. Disconnect the ignition cable at the SPARK terminal on the module.

▲ WARNING

ELECTROCUTION HAZARD CAN CAUSE SERIOUS INJURY OR DEATH. When performing the following steps, do not touch stripped end of jumper or SPARK terminal. The ignition circuit generates over 10,000 volts and electrical shock can result.

1. Energize the module and immediately touch one end of the jumper firmly to the GND terminal on the module. Move the free end of the jumper slowly toward the SPARK terminal until a spark is established.
2. Pull the jumper slowly away from the terminal and note the length of the gap when sparking stops, check as follows:

Step 4: Check pilot and main burner lightoff.

1. Set the thermostat to call for heat.
2. Watch the pilot burner during the ignition sequence to be sure:
   • Ignition spark continues after the pilot is lit.
   • Pilot lights and the spark stops, but the main burner does not light.
   • Pilot lights, the spark stops and the main burner lights, but the system shuts down.
3. If so, verify adequate flame current as follows:
   • Turn off the furnace at the circuit breaker or fuse box.
   • Clean the flame rod with an emery cloth.
   • Make sure the electrical connections are clean and tight. Replace the damaged wire with moisture-resistant No. 18 wire rated for continuous duty up to 105°C (221° F).
   • Check for a cracked ceramic insulator, which can cause short to ground, and replace the igniter-sensor or sensor, if necessary.
   • At the gas control, disconnect the main valve wire from the TH or MV terminal.
   • Turn on the power and set the thermostat to call for heat. The pilot should light but the main burner remains off because the main valve actuator is disconnected.
   • Check the pilot flame. Make sure it is blue, steady and envelops 3/8 to 1/2 in. (10 to 13 mm) of the flame rod. See Fig. 6 for possible flame problems and the causes.
   • If necessary, adjust the pilot flame by turning the pilot adjustment screw on the gas control clockwise to decrease or counterclockwise to increase the pilot flame. Following adjustment, always replace the pilot adjustment cover screw and tighten firmly to assure proper gas control operation.
   • Set the thermostat below the room temperature to end the call for heat.
4. Recheck ignition sequence as follows:
   • Reconnect the main valve wire.
   • Set the thermostat to call for heat.
   • Watch the ignition sequence at the burner.
   • If spark continues after the pilot lights, replace the ignition module.
   • If the main burner does not light or if the main burner lights but the system locks out, check the module, ground wire, and gas control, as described in the Troubleshooting Guide, see Fig. 7.

Fig. 6. Examples of unsatisfactory pilot flames:

• SMALL BLUE FLAME: Cause: Lack of gas (clogged orifice/filter, low supply pressure, minimum pilot adjustment).
• LAZY YELLOW FLAME: Cause: Lack of air (dirty orifice, dirty lint screen, dirty primary air opening, minimum pilot adjustment).
• WAVING BLUE FLAME: Cause: Excessive draft at pilot location, recirculating products of combustion.
• NOISY LIFTING BLOWING FLAME: Cause: High gas pressure.
• HARD SHARP FLAME: Cause: High gas pressure, orifice too small. This flame is characteristic of manufactured gas.

Fig. 7. S8610U Troubleshooting Guide.

This flowchart guides troubleshooting:

1. START
2. Turn off gas supply. Turn thermostat (controller) to call for heat.
3. Check power to module (24V nominal) at TH-W and 24V terminals.
4. If vent damper is connected, check line voltage, transformer, limit controller, thermostat, and air proving switch. Verify vent damper is open.
5. If spark is not across igniter/sensor gap:
   • Pull ignition lead and check spark at module.
   • If spark is not okay:
     • Check vent damper plug status (if applicable); replace vent damper if necessary.
     • On other models, replace module.
   • If spark is okay:
     • Check ignition cable, ground wiring, ceramic insulator, and gap.
     • Check ignition cable boot for melting/buckling; replace and shield if necessary.
6. Turn on gas supply.
7. If pilot burner does not light:
   • Check manual gas valves, tubing, pressures, and pilot burner orifice.
   • Check electrical connections to module and pilot operator.
   • Check for 24 Vac across PV-MV/PV terminals. Replace gas control if voltage is okay, otherwise replace module.
8. If spark stops when pilot is lit:
   • Check continuity of ignition cable and ground wire.
   • Clean flame rod.
   • Check electrical connections to flame rod and module.
   • Check for cracked ceramic flame rod insulator.
   • Check pilot flame is steady, blue, and covers flame rod. Adjust pilot flame if necessary.
   • If problem persists, replace module.
9. If main burner does not light:
   • Check for 24 Vac across MV-MV/PV terminals. Replace module if no voltage.
   • Check electrical connections to module and gas control. Replace gas control or operator if okay.
   • Check continuity of ignition cable and ground wire.
   • Check temperature at igniter-sensor insulator.
   • Check pilot flame covers flame rod.
   • If checks are okay, replace module.
10. If system runs until call for heat ends:
    • Check for proper thermostat operation.
    • Remove MV lead; if valve closes, check controller/wiring. If not, replace gas control.
11. If call for heat ends and system shuts off:
    • Repeat procedure until troublefree operation is obtained.

Fig. 8. Schematic for S8610U.

This schematic diagram illustrates the internal circuitry and external connections of the S8610U module. It shows the flow of power from the transformer through the ON-OFF switch, limit controller, and thermostat to the module. Key internal components like the spark drive circuit, flame detector circuit, low voltage power supply, hybrid circuits, relay drivers, and timing circuits are depicted. External connections include terminals for TH-W, 24V GND, SPARK, SENSE, GND (BURNER), MV, MV/PV, and PV. It also shows the vent damper plug connection. Warnings are provided regarding power supply protection, alternate limit controller locations, fuse function (3A non-replaceable), separate sensor usage, and igniter-sensor configurations.

ANSI STANDARDS

Exhibit A: Recommended Procedure for Safety Inspection of an Existing Appliance Installation as A Preliminary Step to Applying an Automatic Intermittent Pilot System

This procedure is a guide to aid in determining that an appliance is properly installed and in a safe condition for continuing use. It applies to central furnace and boiler installations with atmospheric gas burners, not direct vent types. It emphasizes that generalized procedures cannot anticipate all situations, and deviations may be necessary.

Key steps include:

• Performing a Gas Leakage Test of the appliance piping and control system.
• Visually inspecting the venting system for blockages, restrictions, leakage, or corrosion.
• Shutting off all gas and other fuel-burning appliances in the room.
• Inspecting burners and crossovers for blockage and corrosion.
• Inspecting heat exchangers (warm air heating) for cracks or corrosion.
• Inspecting boilers for water or combustion product leaks.
• Closing building doors/windows and turning on exhaust fans to ensure adequate combustion air.
• Placing the appliance in operation, adjusting the thermostat for continuous operation.
• Determining proper pilot burning and satisfactory main burner ignition by interrupting and re-establishing electrical supply.
• Determining manifold pressure to match original input.
• Visually determining proper main burner gas burning (no floating, lifting, or flashback) and adjusting primary air shutters.
• Checking high/low flame control or flame modulation operation.
• Testing for spillage at the draft hood relief opening.
• Returning doors, windows, fans, and other appliances to their previous conditions.
• Checking limit controller and fan controller operation (warm air heating).
• Checking circulating water pumps, low water cutoffs, and limit controls (boilers).

Exhibit B: Procedure for Installing Automatic Intermittent Pilot Systems

This procedure is a guide for safely installing a listed automatic intermittent pilot system on an existing listed appliance with an atmospheric gas burner, not direct vent type. It assumes a history of safe operation.

Key steps include:

• Performing a safety inspection (refer to Exhibit A).
• Shutting off all gas and electricity to the appliance.
• Installing the automatic intermittent pilot system per manufacturer's instructions.
• Turning on gas and electricity.
• Determining transformer capacity by computing current draw and comparing it to the transformer's VA rating. Replace transformer if necessary.
• Checking the heat anticipator in the comfort thermostat.
• Ensuring wiring connections are tight and wires are secured.
• Conducting a Gas Leakage Test.
• Adjusting thermostat for highest setting, testing manifold pressure, and adjusting pressure regulator.
• Visually determining proper main burner gas burning and adjusting primary air shutters.
• Checking high/low flame control or flame modulation.
• Determining proper pilot ignition and main burner ignition by interrupting and re-establishing electrical supply.
• Testing pilot safety device and turndown characteristics.
• Sequencing the appliance through at least three operating cycles.
• Checking limit controller and fan controller operation (furnaces).
• Checking circulating water pumps, low water cutoffs, and limit controls (boilers).
• Adding required labels to the appliance.

Contact Information

Home and Building Control Honeywell International, Inc. 1985 Douglas Drive North Golden Valley, MN 55422

Home and Building Control Honeywell Limited-Honeywell Limitée 35 Dynamic Drive Scarborough, Ontario M1V 4Z9

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