Before paying a repairman to come to your home when your furnace breaks, there are a few basic things you should try. This is one of them.
Recently my region received a substantial amount of snow. Although it was all blown around, my yard certainly received more than a foot, perhaps 15 inches. The following day, my furnace, an Armstrong Ultra SX 90, did not work.
- Furnace would turn on, hum, make noise
- Air would come out of my vents, but it was not hot air, it was cold air
- I cleared the snow around the air intake and exhaust ports on the outside of my home. If these are blocked, it can cause the furnace to stop working. Clearing these did not help me.
- I cleared the snow around the natural gas meter, which as typical had a vent on it. If the vent is blocked, it can deny gas to the furnace. Clearing this did not help me.
- I searched the internet and found a web page describing exactly my problem with exactly my furnace, but unfortunately my little tubes were not corroded or blocked, so that fix did not work for me.
- Then, following the instructions on the inside of the furnace panel, I turned the whole thing off and turned it back on again. I watched for the fire to come on, but it did not.
I didn't pay the man for his labor; I paid him for his knowledge. I didn't know what a roll-out switch was, but now I do! And so should you! Here is what to do:
- Open the door of your furnace. It lifts up, and the inside should look like this if you have the same furnace I have, an Armstrong Ultra SX 90.
- The roll-out switch is located at the top right of this picture, behind the curvy pipe which takes natural gas up into the silver combustion area.
- Reach back there and press the button on the switch. That's all there is to it.
- The purpose of the roll-out switch is to immediately cut the gas in the event that the combustion box gets too hot. In my case, it probably got too hot because the exhaust or air-intake ports were clogged during the snowstorm in my area, but it could also indicate a furnace part which is beginning to fail. If you have to do this trick more than once, or in suspicious circumstances, then have a technician help you.