Furnace Repair Checklist
1. Examine the Thermostat
First, make sure your thermostat is signaling your heater to start.
- Change the batteries if the monitor is not displaying anything. If the digital monitor is messed up, the thermostat might need to be changed.
- Make sure the button is switched to “heat” instead of “off” or “cool.”
- Make sure the program is set to the right day and time and is scheduled to “run.” If you’re having trouble overriding the setting, adjust the temperature by using the up/down arrows and using the “hold” button. This will cause the furnace to turn on if thermostat is causing a problem.
- Set the temperature setting to 5 degrees hotter than the temperature of the room.
If your heater hasn’t turned on within several minutes, make certain that it has electricity by moving the fan switch from “auto” to “on.” If the fan doesn’t start, your heating system may not have power.
If you have a smart thermostat—for example one made 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 still can’t get your Wi-Fi thermostat to function, call us at (985) 764-2426 for heating and cooling service.
2. Inspect Breakers and Switches
Next, verify your breaker and furnace switch are on.
- Locate your main electrical panel. If you have no idea where it is, keep an eye out for a silver metal box in your basement, garage or closet.
- Make certain that your hands and feet aren’t moist before using the panel or breakers.
- Locate the breaker labeled “furnace” or “heat,” and make sure 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 instantly trips and pops back to “off,” don't try to reset it and call a professional from Mayeuxs AC & Heating at (985) 764-2426 immediately.
Regardless of your furnace’s age or brand, it has at least one regular wall switch installed on or near it.
- Ensure the control is facing up in the “on” placement. If it was shut off, expect your furnace to take up to five minutes to turn on. (If you don’t know where to locate your furnace, look in 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 breakdowns, a dirty, clogged air filter is often the top offender.
If your filter is too dirty:
- Your heating system won’t stay on, or it could overheat from reduced airflow.
- Your gas bills may increase because your heating system is switching on more than it should.
- Your heating system could break down sooner than it should due to the fact a dusty filter triggers it to work harder.
- Your heater can be cut off from power if an extremely filthy filter is the cause of a tripped breaker.
Depending on what type of furnace you have, your air filter can be found in the interior of the blower compartment of your furnace, an attached filter case or wall-mounted return air grille.
To replace your filter:
- Switch off your heater.
- Pull out the filter and hold it up to the light. If you can’t see light through it, use a new one.
- Install the new filter with the arrow motioning toward the heater to prevent damage.
Flat filters ought 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 more frequently.
To make the process easier down the line, use a permanent marker on your heating system outside or ductwork to list the airflow direction and filter size.
4. Inspect the Condensate Pan
Otherwise known as drain pans, condensate pans capture liquid your heater draws from the air.
If moisture is dripping from your heater or its pan has standing water in it, follow these recommendations.
- If your pan contains a drain (look for a PVC pipe), make sure that it isn’t clogged. If it should be drained, get a special pan-cleaning tablet you can buy at home improvement or hardware retailers.
- If your pan contains a pump, check the float switch. If the button can’t be moved from the “up” position with liquid in the pan, call us at (985) 764-2426, because you will likely have to get a new pump.
5. Watch for Furnace Error Codes
If failures continue, peek inside your heater’s plastic window to verify the blower motor’s status. Subject to the type, the light may also be attached on the exterior of your furnace.
If you notice anything other than a solid, colored light or twinkling green light, contact us at (985) 764-2426 for HVAC service. Your heating system might be communicating an error code that requires pro assistance.
6. Brush off the Flame Sensor
If your heater tries to start but turns off without putting out warm air, a dusty flame sensor could be at fault. When this happens, your heating system will try to turn on three times before a safety feature powers it down for approximately an hour.
If you feel okay with removing the panels from your heating system, gently scrubbing your flame sensor is a job you are able to do on your own. Or, one of our heating service professionals is able to do it for you.
If you are fine with cleaning the sensor yourself, you should have:
- A 1/4” hex screwdriver or wrench
- Portion of light grit sandpaper, steel wool or emery cloth
- A dry, clean paper towel
As the next step:
- Shut off the furnace’s power by using 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 heating system’s front panel and track the wire to the flame sensor.
- Unscrew the rod and use your sandpaper, steel wool or emery cloth to lightly clean the metal rod.
- Clear the rod with a paper towel.
- Remount the sensor.
- Replace the furnace doors.
- Turn the furnace’s power back on. It might run through a set of inspections before resuming usual heating. If your heating system doesn’t turn on, the sensor could require replacement or something else might be wrong. If this occurs, contact us at (985) 764-2426 for heating and cooling repair help.
7. Light the Pilot Light
If you have an outdated heater, the pilot light could be extinguished. To relight it, find the directions on a sheet on your heater, or use these recommendations.
- Find the lever on the bottom of your heater marked “pilot,” “on” and “off.”
- Push the switch to the “off” position.
- Wait at least five minutes to limit the possibility for creating a fire.
- Move the knob to “pilot.”
- Push the “reset” button as you bring the flame of a long lighter to the pilot light opening.
- Depress the “reset” switch once the pilot light is lit.
If you have gone through the list twice and the pilot light still won’t light or remain lit, get in touch with us at (985) 764-2426 for furnace service.
Examine Your Fuel Supply
Try using another gas appliance. If it doesn’t operate, your natural gas source might be switched off, or you may have run out of propane.