Furnace Repair Checklist
1. Look at the Thermostat
First, make certain that your thermostat is signaling your heat to turn on.
- Replace the batteries if the screen is blank. If the digital display is mixed up, the thermostat could need to be replaced.
- Ensure the control is set to “heat” instead of “off” or “cool.”
- Make certain the program is displaying the right day and time and is set to “run.” If you’re having trouble overriding the program, regulate the temperature by utilizing the up/down arrows and pressing the “hold” button. This will cause the furnace to ignite if thermostat is causing an issue.
- Set the temperature setting to 5 degrees above the room temperature.
If your furnace hasn’t started within a couple minutes, make sure it has power by moving the fan switch from “auto” to “on.” If the fan doesn’t begin to run, your heater may not have power.
If you use a smart thermostat—like one designed by Nest, Ecobee, Lux, Honeywell or Bosch—troubleshooting will be determined by the model you have. Take a look at the manufacturer’s website for help. If you still can’t get your Wi-Fi thermostat to work, call us at 361-265-4371 for heating and cooling service.
2. Examine Breakers and Switches
Next, confirm your breaker and furnace switch are on.
- Find your main electrical panel. If you don’t know where it is, look for a gray metal box in your basement, garage or closet.
- Make certain that your hands and feet are dry prior to touching the panel or breakers.
- Look for the breaker marked “furnace” or “heat,” and make sure it’s turned “on.” If the breaker has tripped, it will be in the middle or “off” position.
- With 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 get in touch with a team member from Rescue Heating & Air at 361-265-4371 quickly.
Regardless of your furnace’s age or brand, it has at least one ordinary wall switch installed on or close to it.
- Ensure the control is moved up in the “on” spot. If it was turned off, expect your furnace to take 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. Buy a New Air Filter
When we consider furnace problems, a filthy, full air filter is often the top offender.
If your filter is too grungy:
- Your heating system won’t keep heating your home, or it might overheat from limited airflow.
- Your energy costs might go up because your furnace is turning on more than it should.
- Your heating system might break down sooner than it should due to the fact a dusty filter forces it to overwork.
- Your heating system can be cut off from power if an overly clogged filter results in a tripped breaker.
Based on what make of furnace 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:
- Cut the power to your furnace.
- Remove the filter and hold it up to the light. If you can’t notice light through it, replace it.
- Install the new filter with the arrow facing toward the heater to keep damage from happening.
Flat filters ought to be replaced every month, while pleated filters should last about three months. If you have children or pets, you may have to replace your filter sooner.
To make the procedure easier down the line, write with 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 hold water your furnace draws from the air.
If water is seeping from your heating system or its pan is overflowing, try these steps.
- If your pan has a drain (look for a PVC pipe), check that it isn’t full. If it needs to be drained, drop in a special pan-cleaning tablet you can buy at home improvement or hardware stores.
- If your pan contains a pump, check the float switch. If the lever is jammed “up” with standing water in the pan, call us at 361-265-4371, because you will likely have to install a new pump.
5. Watch for Heater Error Codes
If failures persist, look within your furnace’s plastic window to check the blower motor’s status. Subject to the type, the light might also be mounted on the exterior of your furnace.
If you note anything else besides an uninterrupted, colored light or twinkling green light, contact us at 361-265-4371 for HVAC service. Your heating system could be emitting an error code that needs specialized assistance.
6. Brush off the Flame Sensor
If your heater makes an effort to run but switches off without blowing heat, a grimy flame sensor can be responsible. When this happens, your heater will try to ignite three times before a safety feature turns it off for approximately an hour.
If you feel okay with removing the panels from your heater, cleaning your flame sensor is a task you have the ability to do yourself. Or, one of our heating service professionals has the ability to do it for you.
If you are fine with cleaning the sensor personally, 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
- Disable the heater’s power with its wall switch or breaker. If your gas valve isn’t electric, you must switch off the gas along with it.
- Remove the heater’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 rub the metal rod.
- Wipe off the rod with a paper towel.
- Remount the sensor.
- Replace the furnace doors.
- Turn the furnace’s power back on. It could proceed through a set of checks before proceeding with normal running. If your heater doesn’t start, the sensor may have to be replaced or something else may be wrong. If this happens, call us at 361-265-4371 for heating and cooling repair support.
7. Relight the Pilot Light
If you are using an older heater, the pilot light could be extinguished. To relight it, find the guide on a sheet on your heater, or try these steps.
- Locate the lever below your furnace that says “pilot,” “on” and “off.”
- Turn the switch to the “off” position.
- Wait at least five minutes to avoid creating a fire.
- Push the dial to “pilot.”
- Hold down the “reset” lever as you bring 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 list twice and the pilot light still won’t light or stay lit, contact us at 361-265-4371 for furnace service.
Inspect Your Gas Delivery System
Try turning on a second gas appliance. If it doesn’t work, your natural gas source may be turned off, or you may have run out of propane.