Furnace Repair Checklist
1. Check the Thermostat
To begin, make sure your thermostat is telling your furnace to start.
- Swap out the batteries if the display is empty. If the digital display is jumbled, the thermostat may need to be swapped out.
- Make certain that the control is switched to “heat” rather than “off” or “cool.”
- Ensure the program is displaying the appropriate day and time and is programmed to “run.” If you’re having a hard time overriding the setting, regulate the temperature with the up/down arrows and pressing the “hold” button. This will cause the furnace to start if thermostat is causing trouble.
- Increase the temperature setting to 5 degrees warmer than the temperature of the room.
If your heater hasn’t kicked on within a couple minutes, make sure it has electricity by changing the fan switch from “auto” to “on.” If the fan doesn’t operate, your heater may not have power.
If you utilize a smart thermostat—like one designed by Nest, Ecobee, Lux, Honeywell or Bosch—troubleshooting will be determined by the model you have. Refer to the manufacturer’s website for assistance. If you aren’t able to get your Wi-Fi thermostat to work, call us at 562-286-6624 for heating and cooling service.
2. Inspect Breakers and Switches
Next, check if your breaker and furnace switch are on.
- Locate your main electrical panel. If you don’t know where it is, keep an eye out for a silver metal box in your basement, garage or closet.
- Ensure your hands and feet are dry before opening the panel or breakers.
- Look for the breaker marked “furnace” or “heat,” and ensure it’s reading “on.” If the breaker has tripped, it will be in the middle or “off” area.
- Moving one hand, quickly flip the breaker to the “on” position. If the breaker immediately trips and pops back to “off,” don't try to reset it and contact a professional from YES R&M Inc. at 562-286-6624 immediately.
It doesn’t matter how old your furnace is or what brand it is, it has no less than one standard wall switch positioned on or by it.
- Make sure the lever is flipped up in the “on” placement. If it was shut off, anticipate your furnace could take up to five minutes to start. (If you don’t know where to locate your furnace, take a look at your basement, garage or utility closet. It can also be in a crawl space or attic.)
3. Replace the Air Filter
When we think about furnace issues, a filthy, clogged air filter is regularly the top offender.
If your filter is too dirty:
- Your heat won’t keep heating your home, or it could get too hot from reduced airflow.
- Your utility costs may be higher because your heat is operating more often.
- Your heat might break down sooner than it should because a dusty filter causes it to work overtime.
- Your furnace may lose power if an extremely clogged filter causes the breaker to trip.
While it depends on what type of heater you use, your air filter can be found in the interior of the blower compartment of your heating system, an attached filter case or wall-mounted return air grille.
To replace your filter:
- Turn off your furnace.
- Remove the filter and angle it toward the light. If you can’t view light through it, get a new one.
- Insert the new filter with the arrow pointing toward the heater to keep damage from happening.
Flat filters should be replaced monthly, while pleated filters should last about three months. If you have children or pets, you could have to put in a new filter sooner.
To make the process go more quickly down the road, write with a permanent pen on your furnace exterior or ductwork to show the airflow direction and filter size.
4. Examine the Condensate Pan
Commonly known as drain pans, condensate pans hold liquid your heater removes from the air.
If moisture is seeping from within your furnace or its pan has standing water in it, try these guidelines.
- If your pan has a drain (look for a PVC pipe), make sure that it isn’t full. If it requires draining, drop in a special pan-cleaning tablet you can purchase at home improvement or hardware shops.
- If your pan has a pump, check the float switch. If the lever is stuck “up” with standing water in the pan, contact us at 562-286-6624, because you will likely need a new pump.
5. Check for Heating Error Codes
If failures keep on happening, peek inside your furnace’s plastic window to confirm the blower motor’s status. Subject to the brand, the light might also be attached on the surface of your heater.
If you notice anything except a solid, colored light or twinkling green light, call us at 562-286-6624 for HVAC service. Your furnace may be emitting an error code that is calling for professional assistance.
6. Brush off the Flame Sensor
If your heater attempts to start but turns off without putting out warm air, a dirty flame sensor might be responsible. When this occurs, your furnace will attempt to start three times before a safety feature powers it down for approximately an hour.
If you feel confident with opening up your heater, brushing off your flame sensor is a task you can do on your own. Or, one of our heating service professionals is able to finish it for you.
If you want to clean the sensor on your own, you need:
- A 1/4” hex screwdriver or wrench
- Piece of light grit sandpaper, steel wool or emery cloth
- A dry, clean paper towel
As the next step:
- Shut off the furnace’s power with its wall switch or breaker. If your furnace’s gas valve isn’t electric, you have to turn off the gas as well.
- Lift off the heater’s front panel and follow the wire to the flame sensor.
- Take off the rod and use your sandpaper, steel wool or emery cloth to lightly rub the metal rod.
- Clear the rod with a paper towel.
- Put the sensor back in.
- Put the furnace doors back on.
- Switch the furnace’s power back on. It could go through a series of inspections before continuing regular operation. If your heater doesn’t start, the sensor may need to be replaced or something else might be wrong. If this takes place, contact us at 562-286-6624 for heating and cooling repair assistance.
7. Relight the Pilot Light
If you are using an older heating system, the pilot light could be turned off. To relight it, look for the directions on a sheet on your heating system, or try these guidelines.
- Look for the switch beneath your furnace labeled “pilot,” “on” and “off.”
- Move the switch to the “off” position.
- Don’t do anything for at least five minutes to prevent sparking a fire.
- Push the knob to “pilot.”
- Hold down the “reset” lever as you push the flame of a long lighter to the pilot light opening.
- Let go of the “reset” switch once the pilot light is ignited.
If you have used the instructions twice and the pilot light still won’t light or remain ignited, contact us at 562-286-6624 for furnace service.
Check Your Energy Delivery System
Try turning on another gas appliance. If it doesn’t work, your natural gas service may be switched off, or you might have run out of propane.