When I got home this afternoon, I found that the house was just 60ºF inside. Since the thermostat is set to 70º, this brought my attention to the heater. It was blowing cold air. There are a few handy furnace maintenance tips that can be tried before giving the repair guys a call.
Tip #1. Check the furnace filter.
The furnace filter on my furnace model is a 16x20x1″ filter, and according to specifications it should be replaced monthly. If you find the furnace is not blowing warm air, check the filter. If it needs replacing, do so, and then switch the furnace off and back on. It may have an automatic reset button that could trip if the furnace filter is too clogged.
Tip #2. Check the exhaust.
If you have a high-efficiency furnace, it likely is exhausted via pvc pipes out the wall. Check to make sure the exhaust pipes are clear of snow or other debris. If the exhaust is blocked, clear the blockage and then cycle the furnace on and back off. Blowing cold air still? Try another tip.
Tip #3. Look for tripped sensors.
If you’ve cleared the filter and exhaust, a sensor may have been tripped. Turn off power to the furnace, and open the panel to where the blower is. There are a few different types of sensors, but most all of them will have two wires coming out of them, and will have a button that can be pressed to reset it like a circuit breaker. My heater has 4 of these sensors. Push the button on each sensor to reset it, and then replace the door panel. Turn the furnace back on and see if it lights.
Tip #4. Look at the blink code.
Modern heaters have a motherboard, or main circuit board. Often times if there is a problem with the heater, there will be an LED light that will flash a code and give you an idea of what may be the issue. The back of the door panel will likely give information about the code and its meaning.
If you’re still stumped as to the issue with your furnace, you might consult a professional.
Baby, it’s cold outside! You don’t want to be long without heat.
Special thanks to Steve Winkelman of Ritter Heating Electric Cooling & Plumbing for sharing these handy furnace maintenance tips.