Furnace Repair Checklist
1. Inspect the Thermostat
To start, make certain that your thermostat is telling your heater to turn on.
Digital Thermostat
- Swap out the batteries if the display is not displaying anything. If the digital monitor is messed up, the thermostat may need to be changed.
- Make certain that the button is on “heat” instead of “off” or “cool.”
- Make sure the program is set to the right day and time and is scheduled to “run.” If you’re having problems getting out of the program, set the temperature by using the up/down arrows and using the “hold” button. This will cause the furnace to turn on if thermostat is causing an issue.
- Increase the temperature setting to 5 degrees hotter than the room temperature.
If your heater hasn’t started within a couple minutes, make certain that it has power by switching the fan switch from “auto” to “on.” If the fan doesn’t start, your heating system could be without power.
Smart Thermostat
If you use a smart thermostat—like one designed by Nest, Ecobee, Lux, Honeywell or Bosch—troubleshooting will depend on your model. Refer to the manufacturer’s website for assistance. If you aren’t able to get your Wi-Fi thermostat to function, reach us at 847-362-0262 for heating and cooling service.
2. Check Breakers and Switches
Next, verify your breaker and furnace switch are on.
- Find your main electrical panel. If you have no idea where it is, keep an eye out for a gray metal box in your basement, garage or closet.
- Ensure your hands and feet aren’t wet in advance of opening the panel or breakers.
- Find the breaker labeled “furnace” or “heat,” and ensure it’s moved to “on.” If you find that the breaker tripped, it will be in the middle or “off” spot.
- Using one hand, firmly flip the breaker to the “on” position. If the breaker trips right away and pops back to “off,” don't try to reset it and call a team member from TopTec Heating, Cooling, Plumbing & Electrical at 847-362-0262 quickly.
No matter your furnace’s age or brand, it has no less than one ordinary wall switch set on or by it.
- Make sure the switch is moved up in the “on” spot. If it was shut off, expect your furnace to take up to five minutes to ignite. (If you don’t know where your furnace is located, check your basement, garage or utility closet. It could also be in a crawl space or attic.)
3. Buy a New Air Filter
When we think about furnace problems, a dirty, blocked air filter is frequently the top culprit.
If your filter is too dirty:
- Your heat won’t be able to stay on, or it could get too hot from reduced airflow.
- Your utility costs may go up because your heat is running more often.
- Your heat may stop working too soon due to the fact a dirty filter forces it to overwork.
- Your heater may be cut off from power if an extremely filthy filter causes the breaker to trip.
While it depends on what make of furnace you have, your air filter is located in the interior of the blower compartment of your furnace, an attached filter case or wall-mounted return air grille.
To swap out your filter:
- Switch off your heater.
- Take out the filter and hold it up to the light. If you can’t notice light through it, use a new one.
- Insert the new filter with the arrow motioning toward the heater to prevent damage.
Flat filters need to be replaced monthly, while pleated filters should last about three months. If you have children or pets, you could have to change your filter sooner.
To make the procedure go more quickly in the future, write with a permanent pen on your heating system housing or ductwork to indicate the airflow direction and filter size.
4. Look at the Condensate Pan
Also known as drain pans, condensate pans catch liquid your heater pulls from the air.
If liquid is seeping from within your furnace or its pan has too much water in it, use these steps.
- If your pan includes a drain (look for a PVC pipe), check that it isn’t full. If it requires draining, drop in a special pan-cleaning tablet you can get at home improvement or hardware stores.
- If your pan contains a pump, take a look at the float switch. If the switch can’t be moved from the “up” position with standing water in the pan, call us at 847-362-0262, because you will possibly have to install a new pump.
5. Look for Heater Error Codes
If malfunctions persist, peek within your heating system’s plastic window to verify the blower motor’s status. Depending on the brand, the light may also be attached on the surface of your heater.
If you see anything else besides a steady, colored light or twinkling green light, contact us at 847-362-0262 for HVAC service. Your heater may be emitting an error code that requires specialized help.
6. Clean the Flame Sensor
If your heating system makes an effort to operate but shuts off without putting out heated air, a dirty flame sensor might be at fault. When this happens, your furnace will make an attempt to ignite three times before a safety mechanism powers it down for about an hour.
If you feel okay with opening up your heater, brushing off your flame sensor is something you can do on your own. Or, one of our heating service professionals has the ability to finish it for you.
If you want to clean the sensor yourself, you need:
- A 1/4” hex screwdriver or wrench
- Piece of light grit sandpaper, steel wool or emery cloth
- A fresh paper towel
As the next step:
- Turn off the heating system’s power through its wall switch or breaker. If you don’t have an electric gas valve, you must turn off the gas in addition.
- Remove the furnace’s front panel and track the wire to the flame sensor.
- Remove the rod and use your sandpaper, steel wool or emery cloth to lightly clean the metal rod.
- Clear the rod with a paper towel.
- Remount the sensor.
- Put the furnace doors back on.
- Restore power to the furnace. It might proceed through a set of inspections before proceeding with regular operation. If your heating system doesn’t turn on, the sensor could need to be replaced or something else might be causing a problem. If this occurs, call us at 847-362-0262 for heating and cooling repair support.
7. Relight the Pilot Light
If you have an aging heater, the pilot light could be extinguished. To relight it, locate the directions on a label on your heating system, or use these guidelines.
- Locate the toggle beneath your heater that says “pilot,” “on” and “off.”
- Push the switch to the “off” position.
- Wait at least five minutes to prevent creating a fire.
- Turn the switch to “pilot.”
- Push the “reset” lever as you move the flame of a long lighter to the pilot light opening.
- Release the “reset” switch once the pilot light is lit.
If you have followed the instructions twice and the pilot light still won’t burn or stay lit, get in touch with us at 847-362-0262 for furnace service.
Check Your Energy Delivery System
Try turning on an additional gas appliance. If it doesn’t work, your natural gas service could be turned off, or you could be out of propane.