7 Common Issues With Conventional Gas Furnaces

Conventional gas furnaces are typically older furnaces that have standing pilot lights and chimney flues. The annual fuel utilization efficiency (AFUE) rate for these systems is up to 89%, whereas high-efficiency condensing furnaces have ratings of at least 90%. Conventional furnaces can experience the following issues.

  1. Frequently cycling furnace

Short cycling could indicate a dirty filter, faulty thermostat, or blocked exhaust vent. If replacing the filter, troubleshooting the thermostat, or cleaning the vent doesn’t address the problem, contact Tucker Hill for professional HVAC service.

  1. Constantly running blower

There are two potential causes of a constantly running blower. A thermostat set to FAN will cause the blower to run continuously. This may be good if you’d like to filter indoor air or lower the humidity in the home. But typically, adjusting the thermostat to AUTO will stop the system from frequently cycling off and on.

A faulty fan limit switch could also cause short cycling. This switch monitors the temperature in the furnace and shuts down the system once the set temperature has been reached. Resetting the switch can help solve the problem. Or, it may need to be replaced.

  1. Noisy furnace

Loud banging, low-pitched humming, or squealing may be caused by a variety of issues. In some instances, replacing the filter or oiling the blower motor can eliminate the unusual noise. For more serious cases, schedule an appointment with Tucker Hill for a professional inspection.

  1. Unlit pilot light

A strong draft, dirty orifice in the pilot burner, or dirt in the gas tube can cause the pilot light to go out. A faulty thermocouple can cause the gas supply to shut off, as well. Relighting the pilot light or replacing the thermocouple can address this issue.

  1. Failing electronic ignition

Furnaces with electronic ignition can fail if there’s a problem with any of the components. The result could be little to no heat being produced by the furnace. To correct the ignition, try replacing the filter and checking the power and gas line to the furnace.

  1. Mismatched thermostat and furnace

If the wrong type of thermostat is paired with the furnace, there will be problems operating the system. Contact Tucker Hill to find out which type of thermostat you should have with your furnace.

  1. Faulty thermostat

In some cases, a faulty thermostat may be the reason why the furnace isn’t working. If resetting the thermostat doesn’t solve the problem, call Tucker Hill for inspection and repair.