furnace repair

Laguna Niguel is Getting Cold, but My Furnace Wont Turn On

Fixing your furnace might feel like a daunting chore when your heat won’t turn on. But it doesn’t have to be like that.

There are several quick, low-cost fixes you can do yourself to prevent 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 a professional and live in Laguna Niguel, Ocean Air Conditioning and Heating can help you. We work on most brands of heating systems.

If you need a new heating system, we also offer furnace replacement in Laguna Niguel.

While you’re chatting with us, think about a regular furnace maintenance plan from Ocean Air Conditioning and Heating that might help you avoid breakdowns in the future. We can tell you how regularly your furnace should be inspected by one of our NATE-certified experts.

Use our easy guide below to start troubleshooting your furnace. Most of these steps don’t require mechanical skills.

Steps for Furnace Troubleshooting

Check the Thermostat

To start, make sure your thermostat is signaling your furnace to ignite.

If you have a digital thermostat:

  • Replace 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” rather than “off” or “cool.”
  • Ensure the program is showing the correct 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 make the furnace to ignite if thermostat programming is causing a problem.
  • Increase the temperature setting to 5 degrees warmer than the room temperature.
Digital Thermostat

If your furnace hasn’t turned on within few minutes, make sure it has power by toggling the fan switch from “auto” to “on.” If the fan doesn’t start, your furnace could be without power.

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

Lennox Smart Thermostat

Examine Breakers and Switches

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

  • Locate your house’s main electrical panel. If you aren’t sure where it is, keep an eye out 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.
  • Locate 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 touch it and contact a professional from Ocean Air Conditioning and Heating at 949-525-9119 right away.

No matter your furnace’s age or brand, it has at least one standard wall switch located on or by it.

  • Make sure the switch is flipped up in the “on” position. If it was turned off, expect your furnace to take 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 problems, a dirty, clogged air filter is regularly the top culprit.

If your filter is too dirty:

  • Your furnace won’t stay on, or it could overheat from reduced airflow.
  • Your energy bills could go up because your furnace is turning on too often.
  • Your furnace could fail too soon because a dirty filter causes it to overwork.
  • Your furnace can be cut off from power if an extremely 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.

Replacing a furnace filter

To replace your filter:

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

Flat filters should be replaced monthly, 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 put in a new filter more often.

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

Examine the Condensate Pan

Otherwise known as drain pans, condensate pans capture water your furnace pulls 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 get at home improvement or hardware stores.
  • If your pan contains a pump, check the float switch. If the switch is stuck “up” with water in the pan, contact Ocean Air Conditioning and Heating at 949-525-9119, because you will probably need a new pump.

Peek Inside Your Furnace

If malfunctions keep on happening, peek inside your furnace’s plastic window to check 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 other than a steady, colored light or blinking green light, call Ocean Air Conditioning and Heating at 949-525-9119. Your furnace may be communicating an error code that needs professional help.

Clean the Flame Sensor

If your furnace tries to start but switches off without blowing heat, a dirty flame sensor could be at fault. When this occurs, your furnace will try to turn on three times before a safety feature shuts it down 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 experts at Ocean Air Conditioning and Heating 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.
  • Take off the furnace’s front panel and track 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 may proceed through a sequence of checks before resuming regular operation. If your furnace doesn’t start, the sensor may need to be replaced or something else might be wrong. If this happens, call Ocean Air Conditioning and Heating at 949-525-9119 for assistance.

Relight the Pilot Light

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

  • Locate 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.”
  • Hold down 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, contact Ocean Air Conditioning and Heating at 949-525-9119.

Check Your Fuel Source

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

Ocean Air Conditioning and Heating Can Help with Furnace Problems

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

Call us today at 949-525-9119 or use our online scheduler. We’ll come out and diagnose the problem.

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