Furnace Repair Checklist
1. Look at the Thermostat
To start, make sure your thermostat is telling your heater to turn on.
- Change the batteries if the screen is empty. If the digital monitor is messed up, the thermostat could need to be replaced.
- Make sure the switch is set to “heat” instead of “off” or “cool.”
- Make sure the program is showing the correct day and time and is scheduled to “run.” If you’re having a hard time turning off the setting, set the temperature by using the up/down arrows and holding the “hold” button. This will cause the furnace to start if thermostat is causing a problem.
- Increase the temperature setting to 5 degrees above the temperature of the room.
If your heating hasn’t started within a few minutes, make sure it has power by switching the fan switch from “auto” to “on.” If the fan doesn’t start, your heater could be without power.
If you use a smart thermostat—such as one made by Nest, Ecobee, Lux, Honeywell or Bosch—troubleshooting will be determined by the model you have. Check the manufacturer’s website for assistance. If you’re still unable to get your Wi-Fi thermostat to function, reach us at 832-224-3887 for heating and cooling service.
2. Examine Breakers and Switches
Next, confirm your breaker and furnace switch are on.
- Look for your main electrical panel. If you don’t know where it is, search for a gray metal box in your basement, garage or closet.
- Ensure your hands and feet aren’t wet prior to using the panel or breakers.
- Locate the breaker labeled “furnace” or “heat,” and ensure it’s turned “on.” If you discover a tripped breaker, it will be in the middle or “off” position.
- With 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 contact a professional from Air Houston Mechanical LLC at 832-224-3887 quickly.
Regardless of your furnace’s age or brand, it has no less than one regular wall switch positioned on or by it.
- Ensure the lever is facing up in the “on” spot. If it was switched off, expect your furnace to take up to five minutes to start. (If you’re unaware of 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. Get a New Air Filter
When we think about heater problems, a grungy, clogged air filter is frequently the top culprit.
If your filter is too grungy:
- Your heat won’t keep heating your home, or it might get too hot from restricted airflow.
- Your utility bills may be higher because your heat is running more often.
- Your furnace might fail sooner than it should due to the fact a dusty filter causes it to work overtime.
- Your furnace might be cut off from power if an overly dirty filter is the cause of a tripped breaker.
Based on what model of heater you own, your air filter will be in the interior of the blower compartment of your heater, an attached filter case or wall-mounted return air grille.
To replace your filter:
- Cut the power to your heater.
- Remove the filter and tilt it toward the light. If you can’t view light through it, replace it.
- Put in the new filter with the arrow pointing toward the heater to keep damage from happening.
Flat filters need to be replaced once a month, while pleated filters should last about three months. If you have children or pets, you may have to change your filter more often.
To make the process easier down the road, use a permanent writing tool on your heater exterior or ductwork to indicate the airflow direction and filter size.
4. Check the Condensate Pan
Commonly known as drain pans, condensate pans hold liquid your heating system draws from the air.
If water is seeping from your furnace or its pan has too much water in it, try these guidelines.
- If your pan contains a drain (look for a PVC pipe), double-check that it isn’t full. If it should be drained, get a special pan-cleaning tablet you can get at home improvement or hardware stores.
- If your pan contains a pump, inspect the float switch. If the button is stuck “up” with standing water in the pan, call us at 832-224-3887, because you will likely have to install a new pump.
5. Check for Heating Error Codes
If malfunctions keep on happening, look at your heater’s plastic window to confirm the blower motor’s status. Depending on the brand, the light could also be attached on the surface of your heater.
If you note anything other than an uninterrupted, colored light or blinking green light, call us at 832-224-3887 for HVAC service. Your heater may be emitting an error code that needs specialized assistance.
6. Clean the Flame Sensor
If your heater attempts to run but switches off without putting out heat, a filthy flame sensor might be at fault. When this happens, your heater will attempt to ignite three times before a safety feature turns it off for around an hour.
If you feel confident with removing the panels from your heater, gently scrubbing your flame sensor is a job you can do personally. Or, one of our heating service professionals is able to complete it for you.
If you are fine with cleaning the sensor on your own, you require:
- A 1/4” hex screwdriver or wrench
- Bit of light grit sandpaper, steel wool or emery cloth
- An unused paper towel
As the next step:
- Turn off the furnace’s power through its wall switch or breaker. If you don’t have an electric gas valve, you must switch off the gas as well.
- Take off the heater’s front panel and trace the wire to the flame sensor.
- Take off the rod and use your sandpaper, steel wool or emery cloth to carefully clean 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 might proceed through a series of examinations before proceeding with regular heating. If your heater doesn’t turn on, the sensor may need to be replaced or something else could be wrong. If this takes place, get in touch with us at 832-224-3887 for heating and cooling repair assistance.
7. Reignite the Pilot Light
If you are using an aging furnace, the pilot light could be out. To relight it, locate the directions on a sheet on your furnace, or follow these recommendations.
- Find the lever below your heater that says “pilot,” “on” and “off.”
- Push the switch to the “off” position.
- Wait at least five minutes to prevent sparking a fire.
- Turn the knob to “pilot.”
- Press the “reset” switch as you bring the flame of a long lighter to the pilot light opening.
- Release the “reset” switch once the pilot light is lit.
If you have gone through the instructions twice and the pilot light still won’t ignite or remain burning, call us at 832-224-3887 for furnace service.
Inspect Your Fuel Supply
Try turning on a second gas appliance. If it doesn’t function, your natural gas delivery might be turned off, or you may have run out of propane.