Running Furnace Without Gas On

[Travelinon]

Hi everyone,
My wife thinks she may have left the switch in the trailer for the heat on, on the thermostat! I turned the gas outside off when we were there last week! The weather is starting to cool down and she the thermostat set for about 72 degrees. What I was wondering, if the furnace comes on and goes back off, without gas going through, will this cause any kind of damage? Weather is cooling down and I suspect the furnace will be running on and off! Thank you in advance!

[JimD]

In theory the furnace should shut down in an error condition. It will come on, sense the blower operation, and then attempt to light. When that operation fails, the furnace will try again and finally give up.

[Jagiven]

Originally Posted by JimD

In theory the furnace should shut down in an error condition. It will come on, sense the blower operation, and then attempt to light. When that operation fails, the furnace will try again and finally give up.

X2, I accidentally tried it a few years back. I just turned the gas on and purged the line (lite the stove) then turned the furnace off and back on. Worked fine.

[Travelinon]

Originally Posted by Jagiven

X2, I accidentally tried it a few years back. I just turned the gas on and purged the line (lite the stove) then turned the furnace off and back on. Worked fine.

Okay great, thank you!

[2edgesword]

If you get gas, purge the line (light one of the burners on the stove to insure all the air is out of the line) and the furnace won't ignite it may need to be manually reset, probably just a matter of pushing a button or flipping a switch. This is designed into the system so the ignitor won't continue to try to ignite the furnace with no gas in the line.

[Travelinon]

Thank you for all your help! Went to the trailer and purged the gas line and the furnace did come back on! Doesn't seem to be any damage to the fan or the ignitor! Happy camping!