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 | TROUBLESHOOTING GUIDE | 
| Main power light is not lit. | Make sure that water heater is plugged in. | 
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 | When the switch is on, is there 120VAC between L1 and N on the terminal block? If not, then | 
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 | check for loose wire connections on the “Power Switch Wire Harness.” If connections are ok, then | 
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 | replace the switch. | 
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 | If there is voltage between L1 and N then the light on the switch is burnt out. Replace switch. | 
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| Thermostat does not call for heat. | Make sure that the temperature of the tank is cool. | 
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 | If the thermostat does not call for heat, then check the PRIMARY voltage across the “Transformer”. | 
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 | If there is voltage across the PRIMARY, then check the voltage across the SECONDARY leads of | 
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 | the “Transformer”. | 
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 | Install a jumper wire from N.O. terminal to the COM terminal on the “Thermostat PC Board.” If | 
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 | the thermostat calls for heat after installing a jumper wire then check the “Thermostat Sensor | 
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 | Probe” leads for proper resistance with an OHM meter (See appendix A). | 
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 | If sensor reading are not correct, replace “Thermostat Sensor Probe.” | 
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 | If the sensor readings are correct, then check “Potentiometer” for the proper resistance. If the | 
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 | readings are correct, then replace the “Thermostat PC Board”, otherwise replace the | 
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 | “Potentiometer.” | 
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| Ignition module “Power” LED is not lit. | Check for 120 VAC at the ignition module on “120 VAC IN.” If there is voltage, then replace the | 
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 | ignition module. | 
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 | If there is not any voltage, check the voltage across the transformer as previously described. | 
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| Blower does not energize. | Is the “Vacuum Switch” (air intake switch) N.C.? If no, then check the hose and see if it is filled | 
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 | with condensate. If the hose is not filled with condensate, then replace vacuum switch. If filled, | 
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 | empty hose. | 
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 | Is the “Pressure Switch” (exhaust pressure switch) N.O.? If no, then check the hose and see if it | 
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 | is filled with condensate. If the hose is not filled with condensate, then replace pressure switch. | 
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 | If filled empty hose. | 
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 | Is the “Collector Limit Switch” N.C.? If no, then reset switch. If this switch trips more than 3 | 
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 | times, call service. | 
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 | If all items above are ok, then replace the blower. | 
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| Ignitor does not glow. | Is there voltage to the “Hot Surface Ignitor”? Check for 120VAC to the ignitor from the ignition | 
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 | module. | 
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 | Is there continuity across the “Hot Surface Ignitor?” If no, then replace hot surface ignitor. If | 
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 | yes, then replace the ignition module. | 
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| Main valve does not turn on. | Put your hand on the gas valve. When the “Valve” LED lights on the ignition module, can you | 
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 | feel it energize? If not, then check the voltages at the ignition module across pins 2 and 7 on | 
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 | the plug “CONTROL”. If there is 24 VAC across these pins, then check to see if the “Rectifier | 
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 | Harness” is secure. If it is secure, then replace the “Gas Valve”. | 
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 | If you can feel the gas valve energize, check the main gas supply is not in the off position. | 
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| Burner Flame keeps going out. | Is there minimum gas supplied to water heater as stated on the rating plate? If not, then | 
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 | increase the supply pressure to the water heater. | 
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 | Measure the microAmps through the flame sensor using a multimeter. Is there at least 4 | 
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 | microAmps? If not, then replace the “Flame Sensor” or flame sensor wire. | 
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| Thermostat does not satisfy. | Is the tank temperature above the temperature set point? | 
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 | Does the T&P relief valve leak? If yes, then replace “Thermostat PC Board.” | 
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| Blower did not post purge | Check “Vacuum Switch” (air intake switch) as previously mentioned. | 
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 | Check “Pressure Switch” (exhaust pressure switch) as previously mentioned. | 
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 | Check “Collector Limit Switch” as previously mentioned. | 
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 | If above switches are all ok, then replace “Ignition Module.” | 
| 2 0 | 9/07 Printed in USA |