Forum Discussion
Harvard
Nov 18, 2014Explorer
QUOTE: "I forgot to turn the thermostat off before going out in search of a space heater, came back about 4 hours later and the furnace was finally working.
It worked perfectly for about 5 hours (I didn't even have to turn the thermostat on and off a million times to get it to work when the temp. fell).
This morning (when it was 4 degrees, as luck would have it) it reverted back to what it was doing before (blower runs, no ignition)." END QUOTE
There is a remote possibility of an oil trap in the copper line to the furnace which may pass gas when warm (low viscosity) but not when cold (high viscosity). If convenient do a bubble check for gas pressure at the furnace gas connection if and when you are going to disconnect same.
It worked perfectly for about 5 hours (I didn't even have to turn the thermostat on and off a million times to get it to work when the temp. fell).
This morning (when it was 4 degrees, as luck would have it) it reverted back to what it was doing before (blower runs, no ignition)." END QUOTE
There is a remote possibility of an oil trap in the copper line to the furnace which may pass gas when warm (low viscosity) but not when cold (high viscosity). If convenient do a bubble check for gas pressure at the furnace gas connection if and when you are going to disconnect same.
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