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Heating Troubles That May Be the Fault of the Air Filter

air-fliter-cuModern heating systems are normally reliable, year after year, provided they receive a professional installation by licensed HVAC technicians and continue to have annual maintenance. But no system can ever be 100% reliable, and no amount of care can protect a heater from all malfunctions. At some point in your current heater’s service life, you may need to call for heating repair in Fresno, CA from our trained team.

One of the more common problems that affect forced-air systems (which include all types of furnace and heat pumps) is trouble with the air filter. This isn’t a filter for providing better indoor air quality, but the standard filter attached to the HVAC cabinet that stops dust and dirt from getting into the heater through the return air vents. An air filter clogs over time and must be replaced every 1 to 3 months so air can flow freely through the blower and heater.

If a clogged filter is left in place, it can lead to these heating problems:

  • Cold spots: When the filter chokes off the airflow into the heater, it lowers the air pressure throughout the ventilation system. The amount of air from the vents will drop—and so will temperatures in the rooms. At the first sign of rooms that are colder than they should be, we recommend checking on the air filter (more on how to do this below). Put in a new filter if the current one is clogged.
  • The heater shutting down abruptly: A clogged filter can make a heater shut down. If the strain placed on the blower fan is too high, the fan motor might overload the circuit and trip the circuit breaker. This cuts off electrical power to the blower and the furnace won’t work. The clogged filter can also trap enough heat inside a gas furnace that the furnace’s limit switch will activate to shut the system off.
  • High heating costs: When you have a stuffed-up nose, your lungs have to put in more work to draw in air. A similar problem occurs with clogged filters: the reduction in airflow places extra strain on the blower motor, forcing it to draw on more electricity. This lowers the efficiency of the system and raises heating costs.
  • Damage to the blower fan: This can happen if the filter becomes excessively clogged. Pleated filters, one of the most common types, may bend and collapse from the pressure and fall into the blower fan. This is rare, but it does happen in situations where changing the filter has been neglected for too long.

If you don’t know where the air filter is on your heating system, look over the cabinet at the spot where the return air duct connects to the blower. In most HVAC layouts, the filter is in a slot at this point. To change the filter, slide it out of the slot and put in a new one, making sure the guiding arrows face the right direction. During routine maintenance, our technicians will change out the filter for you. You can always ask them for assistance showing you how it’s done.

Purl’s Sheet Metal & Air Conditioning: Quality Is the Cornerstone of Our Business Since 1952.

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