Furnace Repair Checklist
1. Look at the Thermostat
To start, ensure your thermostat is instructing your furnace to turn on.
- Change the batteries if the display is empty. If the digital monitor is scrambled, the thermostat could need to be replaced.
- Make certain that the button is on “heat” as opposed to “off” or “cool.”
- Ensure the program is showing the correct day and time and is set to “run.” If you’re having trouble overriding the program, regulate the temperature by using the up/down arrows and holding the “hold” button. This will cause the furnace to ignite if thermostat is causing trouble.
- Turn the temperature setting to 5 degrees warmer than the temperature of the room.
If your heating hasn’t kicked on within a few minutes, make sure it has juice by changing the fan switch from “auto” to “on.” If the fan doesn’t start, your heating system may not have power.
If you utilize a smart thermostat—such as one manufactured by Nest, Ecobee, Lux, Honeywell or Bosch—troubleshooting will depend on your model. Take a look at the manufacturer’s website for help. If you’re still unable to get your Wi-Fi thermostat to function, reach us at 530-885-8081 for heating and cooling service.
2. Examine Breakers and Switches
Next, check if your breaker and furnace switch are on.
- Look for your main electrical panel. If you aren’t sure 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.
- Find the breaker titled “furnace” or “heat,” and double-check it’s reading “on.” If you find that the breaker tripped, it will be in the middle or “off” position.
- With one hand, steadily turn the breaker to the “on” position. If the breaker instantly trips and pops back to “off,” don't try to reset it and contact a team member from Forster Heating at 530-885-8081 immediately.
Regardless of your furnace’s age or brand, it has no less than one ordinary wall switch set on or close to it.
- Ensure the lever is moved up in the “on” position. If it was turned off, expect your furnace to take up to five minutes to turn on. (If you don’t know where your furnace is located, check your basement, garage or utility closet. It might also be in a crawl space or attic.)
3. Put in a New Air Filter
When we consider furnace issues, a dirty, blocked air filter is often to blame.
If your filter is too grungy:
- Your heat won’t stay on, or it may get too warm from limited airflow.
- Your heating bills may be higher because your furnace is turning on more than it should.
- Your heat could break down too soon since a dirty filter triggers it to work harder.
- Your heater can be cut off from power if an excessively dirty filter causes the breaker to trip.
Based on what type of heating system you own, your air filter can be found inside the blower compartment of your heater, 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 view light through it, get a new one.
- Put in the new filter with the arrow motioning toward the heating system to prevent damage.
Flat filters should be replaced once a month, while pleated filters should last about three months. If you have children or pets, you might have to put in a new filter more often.
To make the process go more quickly down the road, use a permanent writing tool on your heating system exterior or ductwork to show the airflow direction and filter size.
4. Check the Condensate Pan
Otherwise known as drain pans, condensate pans hold moisture your heater pulls from the air.
If water is leaking from your furnace or its pan is overflowing, use these steps.
- If your pan has a drain (look for a PVC pipe), double-check that it’s clear. If it needs to be drained, get a special pan-cleaning tablet you can purchase at home improvement or hardware stores.
- If your pan contains a pump, check the float switch. If the lever is stuck “up” with water in the pan, call us at 530-885-8081, because you will probably need a new pump.
5. Look for Heater Error Codes
If failures keep on happening, take a look within your heating system’s plastic window to verify the blower motor’s status. Depending on the model, the light could also be attached on the surface of your heating system.
If you see anything other than a solid, colored light or twinkling green light, call us at 530-885-8081 for HVAC service. Your furnace might be emitting an error code that is calling for pro help.
6. Brush off the Flame Sensor
If your furnace attempts to start but switches off without putting out warm air, a dirty flame sensor could be to blame. When this occurs, your furnace will make an attempt to turn on three times before a safety feature powers it down for approximately an hour.
If you feel comfortable with opening up your furnace, gently scrubbing your flame sensor is a job you can do on your own. Or, one of our heating service specialists can finish it for you.
If you are fine with cleaning the sensor on your own, you should have:
- A 1/4” hex screwdriver or wrench
- Portion of light grit sandpaper, steel wool or emery cloth
- A fresh paper towel
- Shut off the heating system’s power with its wall switch or breaker. If your gas valve isn’t electric, you have to switch off the gas along with it.
- Lift off the heating system’s front panel and track the wire to the flame sensor.
- Remove the rod and use your sandpaper, steel wool or emery cloth to carefully rub the metal rod.
- Clean the rod with a paper towel.
- Screw the sensor back in.
- Put the furnace doors back on.
- Restore power to the furnace. It could go through a sequence of inspections before resuming regular running. If your furnace doesn’t turn on, the sensor might have to be replaced or something else may be creating an issue. If this happens, contact us at 530-885-8081 for heating and cooling repair support.
7. Relight the Pilot Light
If you have an outdated heater, the pilot light could be extinguished. To relight it, find the instructions on a sheet on your furnace, or use these recommendations.
- Locate the toggle below your heating system marked “pilot,” “on” and “off.”
- Turn the switch to the “off” position.
- Don’t do anything for at least five minutes to limit the possibility for starting a fire.
- Move the knob to “pilot.”
- Hold down the “reset” lever as you bring the flame of a long lighter to the pilot light opening.
- Release the “reset” button once the pilot light is ignited.
If you have followed the instructions twice and the pilot light still won’t light or keep lit, call us at 530-885-8081 for furnace service.
Check Your Fuel Source
Try switching on an additional gas appliance. If it doesn’t operate, your natural gas service might be shut off, or you might have run out of propane.