Furnace Repair Checklist
1. Check the Thermostat
First, ensure your thermostat is signaling your heater to turn on.
- Replace the batteries if the monitor is empty. If the digital screen is jumbled, the thermostat may need to be changed.
- Make sure the button is set to “heat” instead of “off” or “cool.”
- Make sure the program is showing the appropriate day and time and is set to “run.” If you’re having problems turning off the program, regulate the temperature by using the up/down arrows and holding the “hold” button. This will cause the furnace to turn on if thermostat is causing trouble.
- Turn the temperature setting to 5 degrees warmer than the temperature of the room.
If your heater hasn’t started 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 could be without power.
If you utilize a smart thermostat—like one manufactured by Nest, Ecobee, Lux, Honeywell or Bosch—troubleshooting is very model-specific. Refer to the manufacturer’s website for support. If you aren’t able to get your Wi-Fi thermostat to work, call us at 925-233-6238 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 have no idea where it is, keep an eye out for a metallic metal box in your basement, garage or closet.
- Ensure your hands and feet aren’t moist in advance of touching the panel or breakers.
- Look for the breaker titled “furnace” or “heat,” and double-check it’s moved to “on.” If the breaker has tripped, it will be in the middle or “off” spot.
- Moving one hand, firmly 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 an expert from Clean Air HVAC at 925-233-6238 quickly.
No matter your furnace’s age or brand, it has at minimum one regular wall switch positioned on or near it.
- Make sure the lever is moved up in the “on” position. If it was turned off, it could take your furnace up to five minutes to turn on. (If you don’t know where your furnace is located, look in your basement, garage or utility closet. It could also be in a crawl space or attic.)
3. Replace the Air Filter
When we think about heater problems, a filthy, clogged air filter is frequently to blame.
If your filter is too dirty:
- Your heating system won’t keep heating your home, or it may get too hot from restricted airflow.
- Your utility costs may increase because your furnace is switching on more than it should.
- Your furnace might fail prematurely due to the fact a filthy filter causes it to overwork.
- Your heating system may be cut off from power if an extremely filthy filter results in a tripped breaker.
Depending on what model of furnace 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 heating system.
- Remove the filter and tilt it toward the light. If you can’t view light through it, use a new one.
- Install the new filter with the arrow facing toward the heating system to keep damage from happening.
Flat filters need to be replaced every month, while pleated filters should last about three months. If you have children or pets, you might have to change your filter sooner.
To make the process smoother in the future, write with a permanent marker on your furnace outside or ductwork to list the airflow direction and filter size.
4. Check the Condensate Pan
Commonly known as drain pans, condensate pans catch water your heater removes from the air.
If liquid is seeping from within your heating system or its pan is overflowing, follow these guidelines.
- If your pan contains a drain (look for a PVC pipe), double-check that it isn’t full. If it needs to be drained, use a special pan-cleaning tablet you can purchase at home improvement or hardware stores.
- If your pan uses a pump, check the float switch. If the button is jammed “up” with standing water in the pan, reach us at 925-233-6238, because you will likely have to install a new pump.
5. Watch for Heater Error Codes
If malfunctions continue, look within your furnace’s plastic window to verify the blower motor’s status. Depending on the type, the light might also be attached on the exterior of your heater.
If you notice anything other than a solid, colored light or flickering green light, contact us at 925-233-6238 for HVAC service. Your heater may be emitting an error code that requires expert service.
6. Brush off the Flame Sensor
If your furnace attempts to run but shuts off without distributing warm air, a dusty flame sensor could be responsible. When this takes place, your furnace will attempt to turn on three times before a safety feature shuts it down for approximately an hour.
If you feel confident with removing the panels from your furnace, brushing off your flame sensor is a task you have the ability to do on your own. Or, one of our heating service experts can complete it for you.
If you are fine with cleaning the sensor personally, 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 heating system’s power with its wall switch or breaker. If you don’t have an electric gas valve, you have to shut off the gas along with it.
- Lift off the heating system’s front panel and trace the wire to the flame sensor.
- Unscrew the rod and use your sandpaper, steel wool or emery cloth to lightly scrub the metal rod.
- Clean the rod with a paper towel.
- Screw the sensor back in.
- Secure the furnace doors.
- Turn the furnace’s power back on. It may go through a sequence of examinations before proceeding with regular heating. If your heater doesn’t turn on, the sensor could have to be replaced or something else could be causing a problem. If this happens, call us at 925-233-6238 for heating and cooling repair help.
7. Light the Pilot Light
If you own an older heating system, the pilot light could be out. To reignite it, look for the directions on a sticker on your heater, or follow these guidelines.
- Locate the lever beneath your furnace labeled “pilot,” “on” and “off.”
- Move the switch to the “off” position.
- Wait at least five minutes to avoid sparking a fire.
- Move the knob to “pilot.”
- Press the “reset” lever as you push the flame of a long lighter to the pilot light opening.
- Release the “reset” button once the pilot light is ignited.
If you have gone through the guide twice and the pilot light still won’t ignite or keep ignited, call us at 925-233-6238 for furnace service.
Double-Check Your Energy Source
Try switching on a second gas appliance. If it doesn’t work, your natural gas source could be turned off, or you may have run out of propane.