Dvs-36 & Dvs-42 Intermittent Pilot Troubleshooting - White Mountain Hearth DVS-30-2, DVS-30RF-2, DVS-36-2, DVS-36IP-2, DVS-36RF-2, DVS-42-2, DVS-42IP-2, DVS-42RF-2 Installation And Owner's Manual

DVS-36 & DVS-42 INTERMITTENT PILOT TROUBLESHOOTING
GENERAL: All furnaces have been fire-tested to check for
proper operation. This includes, main burner flame, pilot
flame, fan operation, fan control, limit control and automatic
valve operation. If the furnace fails to function on initial
installation, it is advisab\le to re-check the following:
1. 115 volts to the junction box.
2. Inlet gas pressure.
3. The 24 volt system.
4. Type of gas being used and that shown on the rating
label.
The Service Department at Empire Comfort Systems, Inc. may
be contacted to assist in servicing furnace.
Servicing the Pilot and Main Burners, Pilot Orifice, and
Main Burner Orifices: Disconnect the gas supply at the inlet
to the control valve. Then remove the burner door to which the
above components are attached.
Servicing The Fan Motor: The upper front panel, the shroud
surrounding the fan blade and fan blade must be removed. See
"Oiling the Motor" paragraph on page 8.
S 8 6 0 0 H I N T E R M I T T E N T I G N I T I O N M O D U L E
SPECIFICATIONS
Lockout timing is 90 seconds. Ignition timing is until pilot
lights or lockout occurs.
Module shuts down and cuts power to gas control on flame
failure. Gas control closes to provide 100 percent lockout on
flame failure. Manual reset required.
ELECTRICAL RATINGS:
Voltage and frequency: 20.5 to 28.5V (24V nom.) 60 Hz.
Current rating: 0.2 A.
Valve contact ratings (at 24 Vac):
Run Inrush
Pilot 1.0 A 10.0 A
Main 1.0 A 10.0 A
SPARK GENERATOR OUTPUT: 13kV peak at 25 pf load.
THERMOSTAT ANTICIPATOR SETTING: 0.2 A plus pilot
valve rating plus main valve rating.
THERMOSTAT COMPATIBILITY: Standard models com-
patible with all open-close switch type 24 Vac thermostats
capable of supplying rated voltage and current to the mod-
ule.
AMBIENT TEMPERATURE RATING: Minus 40 F to plus
175 F (minus 40 C to plus 79 C).
RELATIVE HUMIDITY RATING: 5 to 90 percent RH at 95
F.
FLAME FAILURE RESPONSE TIME: 0.8 seconds at 1.0 uA
flame current.
FLAME CURRENT: 1 uA, min.
CHECKOUT
Check out the gas control system:
1. At initial installation of the appliance.
2. As part of regular maintenance procedures.
3. As the first step in troubleshooting.
4. Any time work is done on the system.
13369-1-0203
CALL SERVICEMAN
STEP 1: Perform Visual Inspection.
A. With power off, make sure all wiring connections are
clean and tight.
B. Turn on power to appliance and ignition module.
C. Open manual shutoff valves in the gas line to the appli-
ance.
D. Do gas leak test ahead of gas control if piping has been
disturbed.
GAS LEAK TEST: Paint pipe joints with rich soap and
water solution. Bubbles indicate gas leak. Tighten joints
to stop leak.
STEP 2: Review Normal Operating Sequence and Module
Specifications.
STEP 3: Reset the Module.
A. Turn the thermostat to its lowest setting.
B. Wait one minute.
As you do Steps 4 and 5, watch for points where operation
deviates from normal. Refer to Troubleshooting Chart to
correct problem.
STEP 4: Check Safety Lockout Operation.
A. Turn gas supply off.
B. Set thermostat above room temperature to call for heat.
C. Watch for spark at pilot burner.
D. Time length of spark operation. Maximum spark time is
90 seconds.
E. Open manual gas cock and make sure no gas is flowing to
pilot or main burner.
F. Set thermostat below room temperature and wait one
minute before continuing.
STEP 5: Check Normal Operation.
A. Set thermostat above room temperature to call for heat.
B. Make sure pilot lights smoothly when gas reaches the pilot
burner.
C. Make sure main burner lights smoothly without flash-
back. Make sure burner operates smoothly without float-
ing or lifting.
D. If gas line has been disturbed, complete gas leak test.
GAS LEAK TEST: Paint gas control gasket edges and all
pipe connections downstream of gas control, including
pilot tubing connections, with rich soap and water solu-
tion. Bubbles indicate gas leaks. Tighten joints and
screws or replace component to stop gas leak.
E. Turn thermostat below room temperature. Make sure
main burner and pilot flames go out.
OPERATION
Module operation can be conveniently divided into two phases
for S8600H. The phases are trial for ignition and main burner
operation.
TRIAL FOR IGNITION
Pilot Ignition
Following call for heat (system start on S8600H), the module
energizes the first main valve operator. The first main valve
opens, which allows gas to flow to the pilot burner. At the
same time, the electronic spark generator in the module pro-
duces a 13,000 volt spark pulse output (at 25 pf load). The
voltage generates a spark at the igniter-sensor that lights the
pilot.
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