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Furnace Repair in San Jose, CA

HVAC man working on a furnace

When your HVAC system won’t kick on, doing your own furnace repair in San Jose, CA, can appear like a big undertaking.

There are several time-saving, low-cost solutions you can take care of on your own to prevent a heating repair call.

If your heater won’t start, won’t run consistently or won’t fire, take a look at the troubleshooting checklist below prior to calling an HVAC pro.

If you realize you need assistance from a heating and cooling professional and live in San Jose, American HVAC Inc can provide assistance to you. We are able to repair most types of heating systems.

CALL NOW 408-215-1018

If you need a new heating system, we also offer furnace installation.

While you’re talking with our team, think over a regular furnace maintenance plan from American HVAC Inc that could help you avoid problems in the future. Our team can inform you about how frequently your HVAC system should be inspected by one of our professionals.

Go through our easy list as demonstrated to get to work on troubleshooting your furnace. The majority of these processes don’t have a need for mechanical abilities to complete your furnace repair.

Furnace Repair Checklist

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1. Inspect the Thermostat

To start, make certain that your thermostat is signaling your heat to ignite.

Digital Thermostat

  • Change the batteries if the screen is empty. If the digital display is jumbled, the thermostat might need to be replaced.
  • Make sure the control is switched to “heat” instead of “off” or “cool.”
  • Make sure the program is set to the right day and time and is scheduled to “run.” If you’re having problems turning off the schedule, adjust the temperature by utilizing the up/down arrows and holding the “hold” button. This will cause the furnace to start if thermostat is causing trouble.
  • Set the temperature setting to 5 degrees above the temperature of the room.

If your heater hasn’t kicked on within a couple minutes, make certain that it has electricity by moving the fan switch from “auto” to “on.” If the fan doesn’t operate, your heating system could be without power.

Smart Thermostat

If you use a smart thermostat—like one made by Nest, Ecobee, Lux, Honeywell or Bosch—troubleshooting will be determined by the model you have. Check the manufacturer’s website for help. If you’re still unable to get your Wi-Fi thermostat to operate, reach us at 408-215-1018 for heating and cooling service.

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2. Check Breakers and Switches

Next, confirm 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 silver metal box in your basement, garage or closet.
  • Ensure your hands and feet are dry in advance of opening the panel or breakers.
  • Locate the breaker titled “furnace” or “heat,” and make sure it’s turned “on.” If the breaker has tripped, it will be in the middle or “off” position.
  • With one hand, firmly 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 contact an expert from American HVAC Inc at 408-215-1018 immediately.

No matter your furnace’s age or brand, it has at least one ordinary wall switch situated on or close to it.

  • Make certain the switch is facing up in the “on” spot. If it was switched off, anticipate your furnace could take up to five minutes to turn on. (If you’re unaware of where to find your furnace, take a look at your basement, garage or utility closet. It could also be in a crawl space or attic.)
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3. Buy a New Air Filter

When we consider heating problems, a dirty, blocked air filter is often to blame.

If your filter is too dusty:

  • Your heating system won’t keep heating your home, or it might get too warm from limited airflow.
  • Your heating costs may go up because your furnace is turning on more than it should.
  • Your furnace might break down prematurely due to the fact a filthy filter triggers it to work harder.
  • Your heater can be disconnected from power if an overly clogged filter is the cause of a tripped breaker.

Based on what make of furnace you own, your air filter can be found inside the blower compartment of your heater, an attached filter case or wall-mounted return air grille.

To put in a new filter:

  • Turn 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.
  • Install the new filter with the arrow motioning toward the heating system 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 change your filter sooner.

To make the procedure smoother down the line, draw with a permanent writing tool on your heater housing or ductwork to list the airflow direction and filter size.

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4. Examine the Condensate Pan

Commonly known as drain pans, condensate pans catch liquid your furnace removes from the air.

If liquid is seeping from your heater or its pan is overflowing, try these guidelines.

  • If your pan includes a drain (look for a PVC pipe), double-check that it isn’t full. If it needs to be drained, drop in a special pan-cleaning tablet you can buy at home improvement or hardware stores.
  • If your pan contains a pump, inspect the float switch. If the switch is jammed “up” with water in the pan, call us at 408-215-1018, because you will likely need a new pump.
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5. Look for Heater Error Codes

If failures continue, peek inside your heating system’s plastic window to confirm the blower motor’s status. Dependent on the model, the light could also be fixed on the surface of your heating system.

If you notice anything else besides a steady, colored light or blinking green light, reach us at 408-215-1018 for HVAC service. Your heating system might be giving an error code that requires pro help.

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6. Clean the Flame Sensor

If your heating system attempts to run but switches off without blowing warmth, a grimy flame sensor could be at fault. When this happens, your furnace will try to ignite three times before a safety feature turns it off for around an hour.

If you feel comfortable with opening up your furnace, cleaning your flame sensor is work you have the ability to do yourself. Or, one of our heating service specialists is able to do it for you.

If you are fine with cleaning the sensor yourself, you require:

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


  • Disable the heater’s power with its wall switch or breaker. If you don’t have an electric gas valve, you will need to switch off the gas along with it.
  • Take off the heating system’s front panel and follow the wire to the flame sensor.
  • Unscrew the rod and use your sandpaper, steel wool or emery cloth to gently clean the metal rod.
  • Clear the rod with a paper towel.
  • Screw the sensor back in.
  • Secure the furnace doors.
  • Restore power to the furnace. It could go through a set of tests before continuing normal heating. If your heating system doesn’t ignite, the sensor may require replacement or something else could be causing a problem. If this happens, call us at 408-215-1018 for heating and cooling repair assistance.
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7. Relight the Pilot Light

If you are using an aging heating system, the pilot light could be out. To reignite it, find the instructions on a label on your furnace, or follow these recommendations.

  • Locate the toggle beneath your heater labeled “pilot,” “on” and “off.”
  • Turn the switch to the “off” position.
  • Take a break for at least five minutes to prevent starting a fire.
  • Move the switch to “pilot.”
  • Push the “reset” lever as you bring the flame of a long lighter to the pilot light opening.
  • Depress the “reset” lever once the pilot light is burning.
  • If you have gone through the instructions twice and the pilot light still won’t ignite or remain burning, contact us at 408-215-1018 for furnace service.

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Inspect Your Gas Delivery System

Try using a second gas appliance. If it doesn’t function, your natural gas service may be shut off, or you might have run out of propane.

We Can Provide Furnace Servicing

Followed our troubleshooting list but your heating system still doesn’t operate?

Call us right away at 408-215-1018 or contact us online. We’ll come out and pinpoint the trouble.


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