WINCHESTER IS GETTING COLD, BUT MY FURNACE WON’T TURN ON

Fixing your furnace might feel like an overwhelming task when your heat won’t turn on. But it doesn’t have to be like that. There are a couple of fast, reasonable fixes you can do by yourself to avoid a furnace repair call. If your furnace won’t turn on, won’t stay on or won’t ignite, try the troubleshooting list below before contacting an HVAC professional. If you find you need help from an expert and live in Winchester, Thornberry Bros Inc can provide assistance to you. We repair most makes of heating systems. If it’s time for a new heating system, we also offer furnace replacement in Winchester. While you’re talking with us, think over an annual furnace maintenance plan from Thornberry Bros Inc that could help you avoid problems in the future. We can tell you how regularly your furnace should be examined by one of our NATE-certified professionals. Use our easy guide below to get started on troubleshooting your furnace.

Furnace Troubleshooting

Check the Thermostat

To begin, make sure your thermostat is signaling your furnace to turn on.

If you have a digital thermostat:

  • Change the batteries if the screen is blank. If the digital screen is jumbled, the thermostat may need to be replaced.
  • Make sure the switch is set to “heat” instead of “off” or “cool.”
  • Ensure the program is set to the right day and time and is set to “run.” If you’re having trouble overriding the program, set the temperature by using the up/down arrows and press the “hold” button. This will cause the furnace to ignite if thermostat programming is causing trouble.
  • Increase the temperature setting to 5 degrees warmer than the room temperature.

Digital Thermostat

If your furnace hasn’t kicked on within few minutes, make sure it has power by toggling the fan switch from “auto” to “on.” If the fan doesn’t begin to run, your furnace may not have power.

If you have a smart thermostat—like one made by Nest, Ecobee, Lux, Honeywell or Bosch—troubleshooting is very model-specific. Check the manufacturer’s website for help. If you still can’t get your Wi-Fi thermostat to work, contact us for assistance.

Smart Thermostat

Examine Breakers and Switches

Next, you will need to check if your breaker and furnace switch are on.

  • Find your house’s main electrical panel. If you have no idea where it is, search for a gray metal box in your basement, garage or closet.
  • Make sure your hands and feet are dry before touching the panel or breakers.
  • Look for the breaker labeled “furnace” or “heat,” and make sure it’s switched “on.” If the breaker has tripped, it will be in the middle or “off” position.
  • Using one hand, firmly switch the breaker to the “on” position. If the breaker immediately trips and pops back to “off,” don’t try to reset it and call a professional from Thornberry Bros Inc at 859-414-0596 right away.

It doesn’t matter how old your furnace is or what brand it is, it has at least one standard wall switch located on or near it.

  • Make sure the switch is flipped up in the “on” position. If it was turned off, it could take your furnace up to five minutes to start. (If you don’t know where to find your furnace, look in your basement, garage or utility closet. It could also be in a crawl space or attic.)

Replace Your Furnace’s Air Filter

When it comes to furnace issues, a grungy, clogged air filter is frequently to blame.

If your filter is too dirty:

  • Your furnace won’t keep heating your home, or it could overheat from restricted airflow.
  • Your energy bills could go up because your furnace is turning on more often.
  • Your furnace could fail sooner than it should because a dirty filter causes it to work overtime.
  • Your furnace can be cut off from power if an excessively dirty filter causes the breaker to trip.

Depending on what model of furnace you use, your air filter is located inside the blower compartment of your furnace, an attached filter case or wall-mounted return air grille.

Furnace Filter

To replace your filter:

  • Turn off your furnace.
  • Pull out the filter and angle it toward the light. If you can’t see light through it, use a new one.
  • Install the new filter with the arrow pointing toward the furnace to avoid damage.

Flat filters should be replaced every month, while pleated filters should last about three months. You can also use a washable filter that will last about 10 years. If you have children or pets, you may have to change your filter sooner.

To make the process go more quickly in the future, use a permanent marker on your furnace housing or ductwork to show the airflow direction and filter size.

Examine the Condensate Pan

Commonly known as drain pans, condensate pans capture water your furnace draws from the air. If water is leaking out of your furnace or its pan has standing water in it, follow these steps:

  • If your pan has a drain (look for a PVC pipe), check that it’s clear. If it needs to be drained, use a special pan-cleaning tablet you can purchase at home improvement or hardware stores.
  • If your pan uses a pump, inspect the float switch. If the switch is stuck “up” with water in the pan, contact Thornberry Bros Inc at 859-414-0596, because you will likely need a new pump.

Peek Inside Your Furnace

If malfunctions continue, take a look inside your furnace’s plastic window to confirm the status of the blower motor. Depending on the model, the light could also be attached on the outside of your furnace.

If you see anything except a steady, colored light or blinking green light, call Thornberry Bros Inc at 859-414-0596. Your furnace may be communicating an error code that requires professional service.

Clean the Flame Sensor

If your furnace tries to start but turns off without putting out heat, a dirty flame sensor could be responsible. When this occurs, your furnace will attempt to ignite three times before a safety feature turns it off for about an hour. If you feel comfortable with opening up your furnace, cleaning your flame sensor is something you can do yourself. Or, one of our HVAC specialists at Thornberry Bros Inc can do it for you.

If you want to clean the sensor yourself, you’ll need:

  • A 1/4” hex screwdriver or wrench
  • Piece of light grit sandpaper, steel wool or emery cloth
  • A dry, clean paper towel

Next:

  • Shut off the furnace’s power by using its wall switch or breaker. If your gas valve is not electric, you will need to shut off the gas as well.
  • Lift off 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.
  • Wipe off the rod with a paper towel.
  • Remount the sensor.
  • Replace the furnace doors.
  • Turn the furnace’s power back on. It could go through a series of checks before proceeding with usual operation. If your furnace doesn’t ignite, the sensor may need to be replaced or something else might be wrong. If this happens, contact Thornberry Bros Inc at 859-414-0596 for assistance.

Relight the Pilot Light

If you have an older furnace, the pilot light could be extinguished. To relight it, find the instructions on a label on your furnace, or follow these steps.

  • Find the switch on the bottom of your furnace labeled “pilot,” “on” and “off.”
  • Turn the switch to the “off” position.
  • Wait at least five minutes to avoid possibly starting a fire.
  • Turn the knob to “pilot.”
  • Push the “reset” button as you bring the flame of a long lighter to the pilot light opening.
  • Release the “reset” button once the pilot light is lit.

If you have followed the instructions twice and the pilot light still won’t light or stay lit, call Thornberry Bros Inc at 859-414-0596.

Check Your Fuel Source

Try switching on another gas appliance. If it doesn’t work, your natural gas service could be turned off, or you could be out of propane.

Thornberry Bros Inc Can Help with Furnace Problems

Followed our troubleshooting guide but your furnace still won’t work?

Call us today at 859-414-0596! We’ll come out and figure out the problem.

Broken AC unit? Furnace trouble?

We can fix that. Trust in Thornberry today.

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