Furnace Repair Checklist
1. Examine the Thermostat
To begin, make sure your thermostat is instructing your heat to turn on.
- Change the batteries if the display is blank. If the digital monitor is messed up, the thermostat could need to be swapped out.
- Make certain that the switch is switched to “heat” instead of “off” or “cool.”
- Ensure the program is displaying the appropriate day and time and is programmed to “run.” If you’re having problems overriding the setting, adjust the temperature with the up/down arrows and pressing the “hold” button. This will cause the furnace to start if thermostat is causing trouble.
- Turn the temperature setting to 5 degrees above what the room temperature currently is.
If your heat hasn’t kicked on within several minutes, ensure it has electricity by moving the fan switch from “auto” to “on.” If the fan doesn’t operate, your heater could be without power.
If you utilize 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 assistance. If you still can’t get your Wi-Fi thermostat to work, reach us at 540-636-3396 for heating and cooling service.
2. Examine Breakers and Switches
Next, verify your breaker and furnace switch are on.
- Find your main electrical panel. If you aren’t sure where it is, look for a gray metal box in your basement, garage or closet.
- Ensure your hands and feet are dry before opening the panel or breakers.
- Look for the breaker labeled “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.
- With one hand, firmly flip the breaker to the “on” position. If the breaker instantly trips and pops back to “off,” don't try to reset it and contact a team member from Dave's Diversified Services at 540-636-3396 quickly.
No matter your furnace’s age or brand, it has at least one standard wall switch situated on or near it.
- Ensure the control is facing up in the “on” position. If it was turned off, anticipate your furnace could take up to five minutes to start. (If you’re unsure where your furnace is located, look in your basement, garage or utility closet. It can also be in a crawl space or attic.)
3. Buy a New Air Filter
When it comes to heater breakdowns, a dirty, blocked air filter is frequently the top offender.
If your filter is too grungy:
- Your heater won’t be able to stay on, or it may get too warm from reduced airflow.
- Your gas expenses may increase because your heating system is switching on more than it should.
- Your heater might stop working prematurely due to the fact a dusty filter causes it to work overtime.
- Your furnace may lose power if an excessively dirty filter is the cause of a tripped breaker.
While it depends on what make of furnace you own, your air filter is located within the blower compartment of your heater, an attached filter case or wall-mounted return air grille.
To put in a new filter:
- Cut the power to your furnace.
- Take out 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 furnace to avoid damage.
Flat filters should be replaced every month, while pleated filters should last about three months. If you have children or pets, you could have to change your filter more frequently.
To make the procedure go more quickly in the future, use a permanent marker on your furnace housing or ductwork to show the airflow direction and filter size.
4. Examine the Condensate Pan
Commonly known as drain pans, condensate pans hold water your furnace pulls from the air.
If moisture is dripping from within your furnace or its pan has standing water in it, try these recommendations.
- If your pan contains a drain (look for a PVC pipe), check that it isn’t clogged. If it should be drained, drop in a special pan-cleaning tablet you can get at home improvement or hardware shops.
- If your pan contains a pump, inspect the float switch. If the switch is stuck “up” with water in the pan, reach us at 540-636-3396, because you will possibly have to install a new pump.
5. Look for Heater Error Codes
If failures continue, look at your heating system’s plastic window to verify the blower motor’s status. Depending on the brand, the light could also be mounted on the surface of your heating system.
If you notice anything other than a steady, colored light or twinkling green light, reach us at 540-636-3396 for HVAC service. Your furnace could be communicating an error code that needs specialized assistance.
6. Scrub the Flame Sensor
If your furnace attempts to start but shuts off without blowing warm air, a dusty flame sensor might be to blame. When this takes place, your heater will try to ignite three times before a safety mechanism shuts it down for about an hour.
If you feel confident with removing the panels from your heater, brushing off your flame sensor is a task you can do on your own. Or, one of our heating service specialists can do it for you.
If you are confident 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
- Disable the heating system’s power with its wall switch or breaker. If your furnace’s gas valve isn’t electric, you will need to shut off the gas in addition.
- Remove the furnace’s front panel and follow the wire to the flame sensor.
- Unscrew the rod and use your sandpaper, steel wool or emery cloth to carefully rub the metal rod.
- Clean the rod with a paper towel.
- Put the sensor back in.
- Put the furnace doors back on.
- Restore power to the furnace. It could run through a series of examinations before resuming normal heating. If your heater doesn’t turn on, the sensor may require replacement or something else might be causing a problem. If this takes place, call us at 540-636-3396 for heating and cooling repair support.
7. Reignite the Pilot Light
If you are using an outdated heating system, the pilot light could be extinguished. To reignite it, look for the instructions on a sheet on your heating system, or follow these recommendations.
- Find the lever beneath 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 sparking a fire.
- Turn the dial to “pilot.”
- Push the “reset” button as you move 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 followed the list twice and the pilot light still won’t ignite or remain lit, contact us at 540-636-3396 for furnace service.
Examine Your Fuel Supply
Try switching on a second gas appliance. If it doesn’t function, your natural gas service may be switched off, or you might have run out of propane.