What Causes A Blown Fuse In The Furnace?

You can wear as many layers of warm woolen clothes, but clothes cannot provide comfort like a furnace system in the winter. If you notice that the fuse blows away often, it is time to contact South County Air Services specializing in HVAC service in Mission Viejo. We can help resolve the issue.

Eight Reasons That Caused The Furnace Fuse To Blow

  1. Excessive Dirt And Dust
    Dust and dirt settle on the furnace components and cause the furnace system to overheat. A safety feature in the HVAC systems shuts down the HVAC unit if the temperature inside the furnace crosses a decided value. In this case, switch off the furnace system for 5-6 hours. In the meantime, dust off the furnace system with a brush and a damp cloth.

  2. Water Leakage
    Water leakage often happens due to blockage in the condensate drain or broken condensate pan. Dripping water can lead to short circuits, and you should look into the matter as early as possible.

    One of the best methods to keep the condensate drain clean is to pour a pan of hot water, a tablespoon of baking soda, and a cup of vinegar into the drain monthly. Take a long brush and remove the blockage if you find it in the condensate pipe.

  3. Electrical Wiring issue
    With time, the insulation over the copper wires gets worn down, or the electric wires loosen from their place. If two wires meet, it can lead to a short circuit, and the furnace fuse will blow off. Contact South County Air Services, the best HVAC service professional in Mission Viejo for a quick check because operating on open wires without safety measures might be dangerous.

  4. Clogged Air Filter
    Almost all furnace repair experts recommend replacing the air filter annually for optimum and efficient operation. A clogged air filter can disrupt the airflow and cause a dirt build-up inside the unit that can shut down the blower motor. It is cost-effective to replace the air filter rather than to replace or repair the blower motor.

  5. Malfunctioning Thermostat
    If your household thermostat has a metal frame, the issue can be due to the thermostat because the internal wires are touching the metal frame. The control board may blow out if the electric wires cannot resist high voltage, and it prevents the draft inducer from starting.

  6. Faulty Components
    Faulty components may also cause the furnace fuse to blow up as they may draw more electricity than required to function appropriately. In most cases, the capacitor, blower motor, transformer, and valves are responsible.

  7. Valve Failure
    In gas furnaces, the blocked valve can expel too much heat or cannot dissipate the heat. It can lead to overheating, and overheating leads to a temporary shutdown.

  8. Issues In The Fuse
    Sometimes, the culprit is the fuse. Due to electrical problems or improper installation, the fuse works inappropriately and causes the furnace system to shut down.


If you want to keep your family and comfort in your residence safe, it is best to call our HVAC technician for maintenance and replace the air filter. Moreover, contact the technician quickly if you find the furnace system working oddly.

Apart from furnace services, South County Air Services technicians are here if you search for air duct cleaning near me online. Dial 949-933-3130 and schedule an appointment for reliable HVAC services today.