Furnace Repair in Lake Forest, CA

HVAC man working on a furnace

When your HVAC system won’t start, doing your own furnace repair in Lake Forest, CA, can feel daunting.

There are a few quick, reasonable fixes you can take on yourself to skip a heater service call.

If your heater refuses to kick on, won’t keep running or won’t ignite, try the troubleshooting checklist below before contacting an HVAC pro.

If you discover you need assistance from a heating and cooling pro and live in Lake Forest, 1st Choice Heating & Air Conditioning, Inc. will be able to assist you. We are able to repair most brands of HVAC systems.

CALL NOW 949-204-0859

If it’s time for a new heating system, we also offer furnace installation.

While you’re chatting with one of our team members, consider a routine furnace maintenance plan from 1st Choice Heating & Air Conditioning, Inc. that could help you avoid problems down the road. Our team can tell you how often your furnace ought to be checked by one of our NATE-certified professionals.

Use our simple list as follows to get started on troubleshooting your HVAC system. A great deal of these steps don’t have the requirement of mechanical know-how to complete your furnace repair.

Furnace Repair Checklist

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1. Check the Thermostat

First, make certain that your thermostat is instructing your furnace to turn on.

Digital Thermostat

  • Change the batteries if the monitor is empty. If the digital screen is scrambled, the thermostat might need to be replaced.
  • Make certain that the control is set to “heat” as opposed to “off” or “cool.”
  • Make certain the program is showing the appropriate day and time and is scheduled to “run.” If you’re having trouble turning off the schedule, regulate the temperature by utilizing the up/down arrows and pressing the “hold” button. This will cause the furnace to turn on if thermostat is causing a problem.
  • Increase the temperature setting to 5 degrees warmer than the room temperature.

If your heater hasn’t kicked on within a few minutes, make sure it has juice by changing the fan switch from “auto” to “on.” If the fan doesn’t begin to run, your heater might not have power.

Smart Thermostat

If you use a smart thermostat—such as one made by Nest, Ecobee, Lux, Honeywell or Bosch—troubleshooting will be determined by the model you have. Check the manufacturer’s website for assistance. If you aren’t able to get your Wi-Fi thermostat to work, call us at 949-204-0859 for heating and cooling service.

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2. Examine 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 gray metal box in your basement, garage or closet.
  • Ensure your hands and feet aren’t wet prior to opening the panel or breakers.
  • Find the breaker titled “furnace” or “heat,” and double-check it’s moved to “on.” If you find that the breaker tripped, it will be in the middle or “off” position.
  • With one hand, firmly flip the breaker to the “on” position. If the breaker trips right away and pops back to “off,” don't try to reset it and get in touch with an expert from 1st Choice Heating & Air Conditioning, Inc. at 949-204-0859 quickly.

Regardless of your furnace’s age or brand, it has no less than one regular wall switch set on or by it.

  • Make sure the control is moved up in the “on” position. If it was shut off, it could take your furnace up to five minutes to ignite. (If you don’t know where to locate your furnace, look in your basement, garage or utility closet. It can also be in a crawl space or attic.)
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3. Replace the Air Filter

When we consider furnace problems, a filthy, blocked air filter is regularly to blame.

If your filter is too grungy:

  • Your heater won’t stay on, or it could get too hot from limited airflow.
  • Your utility costs may be higher because your heat is turning on more often.
  • Your heater could stop working prematurely since a dusty filter forces it to work harder.
  • Your heater can lose power if an overly dirty filter is the cause of a tripped breaker.

While it depends on what type of heating system you have, your air filter can be found inside the blower compartment of your heating system, an attached filter case or wall-mounted return air grille.

To replace your filter:

  • Switch off your furnace.
  • Take out the filter and hold it up to the light. If you can’t see light through it, use a new one.
  • Put in the new filter with the arrow motioning toward the heater to prevent damage.

Flat filters need to be replaced every month, while pleated filters should last about three months. If you have children or pets, you could have to replace your filter more frequently.

To make the process go more quickly down the road, use a permanent pen on your heater exterior or ductwork to indicate the airflow direction and filter size.

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4. Look at the Condensate Pan

Commonly known as drain pans, condensate pans catch liquid your heating system draws from the air.

If moisture is leaking out of your furnace 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, drop in a special pan-cleaning tablet you can purchase at home improvement or hardware retailers.
  • If your pan contains a pump, inspect the float switch. If the button is stuck “up” with standing water in the pan, reach us at 949-204-0859, because you will likely have to get a new pump.
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5. Check for Heater Error Codes

If faults continue, look inside your heating system’s plastic window to confirm the blower motor’s status. Depending on the brand, the light may also be fixed on the exterior of your heater.

If you see anything except an uninterrupted, colored light or blinking green light, call us at 949-204-0859 for HVAC service. Your furnace may be emitting an error code that needs expert help.

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6. Clean the Flame Sensor

If your furnace attempts to run but turns off without distributing warmth, a grimy flame sensor might be responsible. When this occurs, your furnace will attempt to ignite three times before a safety feature shuts it down for approximately an hour.

If you feel confident with opening up your heater, brushing off your flame sensor is a job you have the ability to do on your own. Or, one of our heating service specialists is able to do it for you.

If you are fine with cleaning the sensor personally, you should have:

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


  • Turn off the heating system’s power through its wall switch or breaker. If you don’t have an electric gas valve, you must turn off the gas along with it.
  • Lift off the furnace’s front panel and follow the wire to the flame sensor.
  • Take off the rod and use your sandpaper, steel wool or emery cloth to lightly clean the metal rod.
  • Clear the rod with a paper towel.
  • Put the sensor back in.
  • Secure the furnace doors.
  • Restore power to the furnace. It might proceed through a set of examinations before continuing normal running. If your heating system doesn’t start, the sensor may require replacement or something else could be creating an issue. If this occurs, call us at 949-204-0859 for heating and cooling repair assistance.
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7. Relight the Pilot Light

If you have an older heater, the pilot light could be extinguished. To light it, locate the steps on a sheet on your heater, or use these guidelines.

  • Look for the toggle below your furnace marked “pilot,” “on” and “off.”
  • Move the switch to the “off” position.
  • Wait at least five minutes to avoid sparking a fire.
  • Push the knob to “pilot.”
  • Push the “reset” button as you move the flame of a long lighter to the pilot light opening.
  • Release the “reset” switch once the pilot light is lit.
  • If you have gone through the instructions twice and the pilot light still won’t ignite or stay ignited, get in touch with us at 949-204-0859 for furnace service.

condensate pan icon

Inspect Your Gas Source

Try switching on another gas appliance. If it doesn’t operate, your natural gas delivery may be shut off, or you could be out of propane.

We Can Help with Furnace Servicing

Used our troubleshooting list but your furnace still doesn’t work?

Call us now at 949-204-0859 or contact us online. We’ll make a call at your house and diagnose the issue.


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