Gas Heat

Before you call for Gas Heating help:

This page is for Gas Furnaces And Gas-Packs


Are your filters clean?


Most filters are located in “filter grills” inside your house. They should be kept clean to avoid a multitude of A/C and heating problems. They should be changed about once a month.


Does your system have a supply of gas?

Another thing to check for is if your gas supply is turned “on”.
Every gas system has a way to shut off the gas. This sounds too simple, but we get several calls for this problem every year.
Is your gas meter valve unlocked & "opened"?
If you have LP your tank empty?
There will be a guage under the dome that will tell you what's left in the tank.
It will show in percentages. ( 0 percent is empty)
The gas valve inside the system should be in the "on" position
Is your pilot lit?
Newer furnaces wont have a standing pilot, they use electronic ignition instead, but if you have an older system that has a position on the gas valve which says "pilot" then it will be the type with a standing pilot which is normally lit all the time 24/7. If it has gone out you may choose to try to re light it.
Select "pilot" on the gas valvePress the red button downAs you hold the button down light the pilot with a match.
If the pilot flame is good and thermocouple and gas valve are ok then it will stay lit by itself after about 30 seconds (without holding the button down).
Turn the valve selector to "on"

If you dont have a standing have electronic ignition

Is your combustion blower motor working?

Somewhere in your burner compartment there will be a small motor which drives a small wheel that blows the exhaust gasses out of your furnace.If it isnt working and it's the only thing in that area that's hot then it's off via its internal thermal overload switch. It may just need you to let it cool down for 1/2 hr or so and try it again after moving the shaft by hand to help"free it up" a bit.
Note: At the beginning of the heating season this is the most likely because they have been idle for 6 or 7 months and tend to "freeze up.
Circuit board problems
If your furnace has electrical power but nothing at all works, not even the fan switch at your thermostat (the fan switch is a good test) then check for a fuse on your integrated circuit board. Many boards have a fuse that can be replaced.This will be a small fuse, the same kind used in cars and readily available in auto parts stores. Furnaces will usually have a 3 amp fuse and Gas-Packs will have a 5 amp fuse.

LED codes

Here’s some good news. Many integrated circuit boards are able to diagnose problems for us.
When your system is failing, if you have an LED light on your circuit board then it will be flashing a number of flashes which can be identified on the code list for that particular board.
The list may be on the inside of the electrical panel, or in the owners manual, or perhaps you will have to call the local supply house or factory rep for that particular system.
Note: This LED may be flashing something even when everything is OK. It may just be indicating that it’s beginning a heat cycle, or whatever it happens to be doing at the time.

For more advanced information please go to Service & Maintenance Tips

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