Furnace Repair Checklist
1. Look at the Thermostat
To begin, ensure your thermostat is instructing your heat to turn on.
- Swap out the batteries if the screen is empty. If the digital display is mixed up, the thermostat might need to be changed.
- Make certain that the switch is set to “heat” rather than “off” or “cool.”
- Make certain the program is set to the correct day and time and is scheduled to “run.” If you’re having trouble turning off the schedule, adjust the temperature by utilizing the up/down arrows and holding the “hold” button. This will cause the furnace to turn on if thermostat is causing an issue.
- Turn the temperature setting to 5 degrees above the room temperature.
If your heat hasn’t kicked on within several minutes, ensure it has electricity by toggling the fan switch from “auto” to “on.” If the fan doesn’t operate, your heater may not have power.
If you use a smart thermostat—like one manufactured by Nest, Ecobee, Lux, Honeywell or Bosch—troubleshooting will depend on your model. Check the manufacturer’s website for support. If you aren’t able to get your Wi-Fi thermostat to work, reach us at 510-343-9841 for heating and cooling service.
2. Check Breakers and Switches
Next, verify 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.
- Ensure your hands and feet aren’t moist in advance of using the panel or breakers.
- Find the breaker titled “furnace” or “heat,” and make sure it’s reading “on.” If the breaker has tripped, it will be in the middle or “off” area.
- Using one hand, quickly switch the breaker to the “on” position. If the breaker trips right away and pops back to “off,” don't try to reset it and get in touch with a team member from Contra Costa Heating & AC at 510-343-9841 right away.
It doesn’t matter how old your furnace is or what brand it is, it has at least one standard wall switch set on or by it.
- Ensure the control is moved up in the “on” position. If it was turned off, it could take your furnace up to five minutes to ignite. (If you don’t know where to find your furnace, check your basement, garage or utility closet. It might also be in a crawl space or attic.)
3. Get a New Air Filter
When it comes to heater issues, a grungy, full air filter is often to blame.
If your filter is too grungy:
- Your heat won’t keep heating your home, or it could get too warm from limited airflow.
- Your energy costs could be higher because your heating system is operating more than it should.
- Your heating system may fail too soon due to the fact a filthy filter causes it to work overtime.
- Your heater can lose power if an extremely dirty filter results in a tripped breaker.
Based on what type of heater you have, your air filter can be found inside the blower compartment of your heating system, an attached filter case or wall-mounted return air grille.
To replace your filter:
- Cut the power to your heater.
- Pull out the filter and tilt it toward the light. If you can’t notice light through it, get a new one.
- Put in the new filter with the arrow pointing toward the heater to avoid damage.
Flat filters need to be replaced monthly, while pleated filters should last about three months. If you have children or pets, you might have to put in a new filter sooner.
To make the procedure easier down the line, draw with a permanent marker on your furnace exterior or ductwork to show the airflow direction and filter size.
4. Look at the Condensate Pan
Also known as drain pans, condensate pans capture water your heating system draws from the air.
If moisture is seeping out of your heating system or its pan is overflowing, try these steps.
- If your pan contains a drain (look for a PVC pipe), double-check that it isn’t full. If it requires draining, use a special pan-cleaning tablet you can buy at home improvement or hardware shops.
- 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 liquid in the pan, contact us at 510-343-9841, because you will possibly have to get a new pump.
5. Look for Heater Error Codes
If faults persist, take a look inside your heating system’s plastic window to confirm the blower motor’s status. Dependent on the brand, the light could also be fixed on the exterior of your heating system.
If you notice anything else besides an uninterrupted, colored light or blinking green light, contact us at 510-343-9841 for HVAC service. Your heating system might be giving an error code that needs professional assistance.
6. Scrub the Flame Sensor
If your heater attempts to operate but switches off without distributing heat, a grimy flame sensor might be at fault. When this happens, your heater will make an attempt to turn on three times before a safety mechanism turns it off for about an hour.
If you feel comfortable with opening up your heating system, brushing off your flame sensor is work you are able to do personally. Or, one of our heating service specialists can do it for you.
If you are confident cleaning the sensor yourself, you need:
- A 1/4” hex screwdriver or wrench
- Portion of light grit sandpaper, steel wool or emery cloth
- A dry, clean paper towel
- Disable the furnace’s power with its wall switch or breaker. If you don’t have an electric gas valve, you have to switch off the gas along with it.
- Take off the furnace’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 carefully rub the metal rod.
- Clear the rod with a paper towel.
- Remount the sensor.
- Secure the furnace doors.
- Restore power to the furnace. It could run through a series of examinations before proceeding with regular heating. If your heating system doesn’t turn on, the sensor might have to be replaced or something else could be causing a problem. If this occurs, contact us at 510-343-9841 for heating and cooling repair support.
7. Reignite the Pilot Light
If you have an outdated heating system, the pilot light could be out. To light it, find the directions on a label on your heater, or follow these recommendations.
- Locate the lever on the bottom of your furnace that says “pilot,” “on” and “off.”
- Push the switch to the “off” position.
- Take a break for at least five minutes to prevent starting a fire.
- Turn the dial to “pilot.”
- Press the “reset” button as you move the flame of a long lighter to the pilot light opening.
- Release the “reset” lever once the pilot light is ignited.
If you have tried the guide twice and the pilot light still won’t ignite or stay ignited, contact us at 510-343-9841 for furnace service.
Inspect Your Energy Supply
Try turning on another gas appliance. If it doesn’t operate, your natural gas source could be switched off, or you may have run out of propane.