Furnace Repair Checklist
1. Examine the Thermostat
To start, ensure your thermostat is telling your furnace to turn on.
- Change the batteries if the screen is not displaying anything. If the digital display is messed up, the thermostat might need to be swapped out.
- Ensure the switch is switched to “heat” as opposed to “off” or “cool.”
- Make sure the program is showing the right day and time and is set to “run.” If you’re having problems getting out of the setting, set the temperature with the up/down arrows and holding the “hold” button. This will cause the furnace to start if thermostat is causing an issue.
- Turn the temperature setting to 5 degrees hotter than the temperature of the room.
If your heat hasn’t turned on within a couple minutes, make sure it has power by switching the fan switch from “auto” to “on.” If the fan doesn’t start, your furnace may not have power.
If you have a smart thermostat—such as one manufactured by Nest, Ecobee, Lux, Honeywell or Bosch—troubleshooting is very model-specific. Check the manufacturer’s website for help. If you’re still unable to get your Wi-Fi thermostat to function, contact us at 623-208-6444 for heating and cooling service.
2. Check Breakers and Switches
Next, check if your breaker and furnace switch are on.
- Locate your main electrical panel. If you have no idea where it is, search for a gray metal box in your basement, garage or closet.
- Make sure your hands and feet aren’t moist before touching the panel or breakers.
- Look for the breaker marked “furnace” or “heat,” and double-check it’s reading “on.” If you discover a tripped breaker, it will be in the middle or “off” spot.
- With one hand, steadily switch the breaker to the “on” position. If the breaker immediately trips and pops back to “off,” don't try to reset it and call a professional from Cooler Tymes LLC at 623-208-6444 immediately.
Regardless of your furnace’s age or brand, it has no less than one standard wall switch set on or close to it.
- Make sure the lever is flipped up in the “on” placement. If it was switched off, anticipate your furnace could take up to five minutes to turn on. (If you’re unaware of where your furnace is located, check your basement, garage or utility closet. It might also be in a crawl space or attic.)
3. Get a New Air Filter
When we think about heating breakdowns, a dirty, clogged air filter is frequently the top offender.
If your filter is too dusty:
- Your heating system won’t be able to stay on, or it could get too warm from limited airflow.
- Your energy expenses may be higher because your heating system is operating more than it should.
- Your heating system might fail sooner than it should since a dirty filter causes it to work harder.
- Your heater may be disconnected from power if an overly dirty filter is the cause of a tripped breaker.
While it depends on what model of furnace you own, your air filter is located inside the blower compartment of your heating system, an attached filter case or wall-mounted return air grille.
To put in a new filter:
- Switch off your heating system.
- Remove the filter and tilt it toward the light. If you can’t notice light through it, use a new one.
- Install the new filter with the arrow pointing toward the furnace to keep damage from happening.
Flat filters ought to be replaced monthly, while pleated filters should last about three months. If you have children or pets, you may have to replace your filter sooner.
To make the procedure easier in the future, draw with a permanent marker on your heater housing or ductwork to show the airflow direction and filter size.
4. Examine the Condensate Pan
Also known as drain pans, condensate pans catch liquid your heating system pulls from the air.
If water is leaking from within your heater or its pan has standing water in it, follow these steps.
- If your pan contains a drain (look for a PVC pipe), make sure that it’s clear. If it needs to be drained, get a special pan-cleaning tablet you can buy at home improvement or hardware retailers.
- If your pan has a pump, inspect the float switch. If the switch is stuck “up” with standing water in the pan, contact us at 623-208-6444, because you will probably have to buy a new pump.
5. Look for Furnace Error Codes
If faults continue, peek inside your furnace’s plastic window to confirm the blower motor’s status. Dependent on the type, the light might also be mounted on the outside of your heating system.
If you notice anything other than a solid, colored light or flickering green light, call us at 623-208-6444 for HVAC service. Your heater may be giving an error code that is calling for specialized assistance.
6. Clean the Flame Sensor
If your heater tries to work but shuts off without putting out warm air, a dusty flame sensor can be to blame. When this happens, your furnace will make an attempt to ignite three times before a safety mechanism shuts it down for approximately an hour.
If you feel okay with taking the panels off your furnace, cleaning your flame sensor is something you are able to do yourself. Or, one of our heating service experts has the ability to complete it for you.
If you are fine with cleaning the sensor personally, you should have:
- A 1/4” hex screwdriver or wrench
- Bit of light grit sandpaper, steel wool or emery cloth
- A dry, clean paper towel
- Shut off the furnace’s power through its wall switch or breaker. If you don’t have an electric gas valve, you will need to shut off the gas along with it.
- Take off the heating system’s front panel and follow the wire to the flame sensor.
- Unscrew the rod and use your sandpaper, steel wool or emery cloth to gently clean the metal rod.
- Clean the rod with a paper towel.
- Screw the sensor back in.
- Secure the furnace doors.
- Restore power to the furnace. It may run through a sequence of tests before proceeding with normal heating. If your heating system doesn’t start, the sensor might have to be replaced or something else may be wrong. If this occurs, get in touch with us at 623-208-6444 for heating and cooling repair assistance.
7. Relight the Pilot Light
If you have an outdated heating system, the pilot light could be out. To relight it, find the steps on a sheet on your heating system, or try these recommendations.
- Look for the toggle below your heater that says “pilot,” “on” and “off.”
- Push the switch to the “off” position.
- Take a break for at least five minutes to limit the possibility for starting a fire.
- Push the knob to “pilot.”
- Push the “reset” lever as you push the flame of a long lighter to the pilot light opening.
- Depress the “reset” button once the pilot light is burning.
If you have followed the guide twice and the pilot light still won’t ignite or keep ignited, contact us at 623-208-6444 for furnace service.
Inspect Your Fuel Source
Try using another gas appliance. If it doesn’t work, your natural gas delivery might be switched off, or you could be out of propane.