Furnace Repair Checklist
1. Inspect the Thermostat
To begin, ensure your thermostat is signaling your heater to turn on.
Digital Thermostat
- Replace the batteries if the screen is not displaying anything. If the digital display is jumbled, the thermostat might need to be changed.
- Make sure the control is on “heat” as opposed to “off” or “cool.”
- Ensure the program is set to the appropriate day and time and is programmed to “run.” If you’re having a hard time turning off the program, adjust the temperature by utilizing the up/down arrows and using the “hold” button. This will cause the furnace to turn on if thermostat is causing an issue.
- Turn the temperature setting to 5 degrees warmer than what the room temperature currently is.
If your heating hasn’t turned on within a few minutes, ensure it has juice by changing the fan switch from “auto” to “on.” If the fan doesn’t operate, your heater could be without power.
Smart Thermostat
If you have a smart thermostat—such as one manufactured by Nest, Ecobee, Lux, Honeywell or Bosch—troubleshooting is very model-specific. Refer to the manufacturer’s website for help. If you’re still unable to get your Wi-Fi thermostat to operate, reach us at 302-231-1380 for heating and cooling service.
2. Check Breakers and Switches
Next, check if your breaker and furnace switch are on.
- Look for your main electrical panel. If you don’t know where it is, keep an eye out for a metallic 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 reading “on.” If the breaker has tripped, it will be in the middle or “off” position.
- With one hand, steadily turn the breaker to the “on” position. If the breaker trips right away and pops back to “off,” don't try to reset it and call an expert from SchagrinGAS Company at 302-231-1380 immediately.
No matter your furnace’s age or brand, it has at least one standard wall switch placed on or near it.
- Make certain the control is facing up in the “on” spot. If it was shut off, expect your furnace to take up to five minutes to turn on. (If you’re unaware of where to locate your furnace, take a look at your basement, garage or utility closet. It may also be in a crawl space or attic.)
3. Put in a New Air Filter
When we think about furnace breakdowns, a grungy, blocked air filter is regularly the top culprit.
If your filter is too dusty:
- Your heat won’t be able to stay on, or it could get too hot from reduced airflow.
- Your gas bills could go up because your heating system is turning on more often.
- Your heater could stop working prematurely due to the fact a dirty filter forces it to work overtime.
- Your heater may lose power if an extremely filthy filter causes the breaker to trip.
While it depends on what type of heating system 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 put in a new filter:
- Turn off your heating system.
- Take out the filter and angle it toward the light. If you can’t notice light through it, replace it.
- Put in the new filter with the arrow motioning toward the heater to prevent damage.
Flat filters should be replaced monthly, while pleated filters should last about three months. If you have children or pets, you may have to replace your filter more frequently.
To make the procedure smoother down the road, use a permanent marker on your furnace housing or ductwork to indicate the airflow direction and filter size.
4. Examine the Condensate Pan
Otherwise known as drain pans, condensate pans hold liquid your heating system removes from the air.
If moisture is leaking from within your heating system or its pan has too much water in it, follow these recommendations.
- If your pan includes a drain (look for a PVC pipe), double-check that it’s clear. If it should be drained, get a special pan-cleaning tablet you can purchase at home improvement or hardware stores.
- If your pan uses a pump, take a look at the float switch. If the lever is jammed “up” with water in the pan, reach us at 302-231-1380, because you will likely need a new pump.
5. Look for Heater Error Codes
If failures keep on happening, take a look inside your furnace’s plastic window to verify the blower motor’s status. Depending on the model, the light might also be attached on the surface of your heater.
If you notice anything other than an uninterrupted, colored light or twinkling green light, call us at 302-231-1380 for HVAC service. Your heater might be emitting an error code that needs specialized service.
6. Brush off the Flame Sensor
If your furnace attempts to run but switches off without putting out heated air, a filthy flame sensor could be to blame. When this occurs, your heating system will make an attempt to start three times before a safety device shuts it down for around an hour.
If you feel comfortable with opening up your heating system, brushing off your flame sensor is a task you are able to do on your own. Or, one of our heating service professionals has the ability to complete it for you.
If you want to clean the sensor yourself, you should have:
- A 1/4” hex screwdriver or wrench
- Section of light grit sandpaper, steel wool or emery cloth
- A fresh paper towel
As the next step:
- Disable the heater’s power by using its wall switch or breaker. If your furnace’s gas valve isn’t electric, you must turn off the gas in addition.
- Remove the heater’s front panel and follow 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.
- Screw the sensor back in.
- Secure the furnace doors.
- Turn the furnace’s power back on. It might run through a sequence of checks before resuming regular operation. If your heating system doesn’t ignite, the sensor may require replacement or something else might be creating an issue. If this happens, call us at 302-231-1380 for heating and cooling repair assistance.
7. Light the Pilot Light
If you are using an outdated heating system, the pilot light could be extinguished. To light it, find the steps on a sheet on your heater, or use these guidelines.
- Look for the lever on the bottom of your furnace marked “pilot,” “on” and “off.”
- Push the switch to the “off” position.
- Take a break for at least five minutes to avoid sparking a fire.
- Push the dial to “pilot.”
- Push the “reset” switch as you move the flame of a long lighter to the pilot light opening.
- Let go of the “reset” lever once the pilot light is lit.
If you have gone through the guide twice and the pilot light still won’t burn or remain ignited, get in touch with us at 302-231-1380 for furnace service.
Examine Your Energy Source
Try switching on a second gas appliance. If it doesn’t operate, your natural gas source might be switched off, or you could be out of propane.