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brass213monkey
Dec 13, 2014, 11:01 PM
False flame or gas valve relay shorted indicated on panel . My furnace will ignite for about 1-2 min then shut off . I cleaned the igniter but problem persists . Can someone help me ?

ma0641
Dec 14, 2014, 09:28 AM
If it burns that long, you may have a high temp switch opening or a rollout switch. Make sure filters are clean and you are getting g good airflow.

drtom4444
Dec 15, 2014, 09:16 AM
If it is indicating that a gas valve relay is shorted then you need to trace back the wires attached (All 24 volt control wiring) to the gas valve until you find the relay. One wire will be the low voltage common at the transformer and the other one will be to the normally open contact on the relay. You will have two coil wire terminals which you should test with a meter set to "ohms" (Have the power turned off when using this function.). Read across the terminals and you should have about 200-300 ohms or so. If it is low then you have a short, but also test and see if it reads to ground. Disconnect wires when you do this test or any other test using the "ohm" function. At least one wire should be disconnected, but if you are testing to ground disconnect both wires. Then trace the coil wires back further to see where they lead. You should find a safety somewhere that is opening. You also need to test the gas valve to see if it is shorted or the coil is grounded. Test from a terminal to the body of the valve to test for a ground. If any component is grounded or shorted it is bad. Grounds are best found with the meter set to the highest range on "ohms." Here are some diagrams: https://dl.dropboxusercontent.com/u/8010163/AC%20Wiring%20Diagrams.zip