5 Signs You Need Furnace Repair

Furnace Repair Tips for Homeowners

That was weird! The furnace just came on and then turned right of! Is this a problem? It could be a “short cycle.” Find out what that means below with these Furnace Repair tips for homeowners.

Cycling

Each furnace functions differently. Each home requires heat differently depending on factors like size and insulation. Different outdoor temperatures will also create different needs. On average, a normal furnace will cycle 2 to 5 times per hour and a cycle should last at least 5 minutes.

Short cycles happen when the furnace turns on for a short duration (a few seconds to less than 2 minutes) or cycles that happen frequently, say, every five minutes or so. Both types of short cycles indicate a problem that needs to be addressed. Here are some common causes of furnace short cycles.

Overheating

The heat exchange chamber has a sensor that shuts the heat off if the temperature exceeds a certain threshold. The proper flow of air ensures the heat generated by the furnace will move throughout the house properly and cool the exchange chamber. The chamber will overheat when:

• When several vents get covered, the result is reduced airflow across the heat exchanger, causing the temperature to rise to unsafe levels. Furniture and drapes are frequent culprits. Inspect the supply vents and cold air returns.
• When the filter is covered in dust, airflow is restricted from flowing properly. Set a seasonal calendar reminder to keep your filter changed regularly, a least every 3 months. Check your air filter to see if it needs to be changed.
• Dust builds up on the blower. It will slow, reducing the amount of airflow available. Clean the fins on the blower motor.

Further investigation by an HVAC technician may reveal other variables causing overheating problems.

Thermostat Settings

The thermostat serves as an ON/OFF switch; if the switch malfunctions, it can affect the timing of cycles. Since new thermostats are programmable, take a look to make sure everything is functioning properly.

• If your thermostat is battery-powered, remove the cover plate and replace them with fresh batteries.
• Check the settings and schedule to make sure the thermostat is not the source of the problem.
• If problems persist, an HVAC professional can recalibrate or replace the thermostat.

Combustion Problems

Natural gas or propane furnaces might experience problems with combustion that can cause short cycles.

• A sensor on the burner detects the intensity of the flame. If the sensor is dirty, it can cause false readings that will result in short cycles.
• A problem with the flue may restrict the flow of exhaust. Not only would this result in the buildup of carbon monoxide, but it can also cause an overheating problem as described above.

Wrong Size

• When your HVAC system was designed and installed, a precise calculation was made to determine the size of the system components. If the technician miscalculated and installed a system that is too large, it will function so well that only short cycles are required. This will eventually lead to stress on your HVAC system and can lead to a shortened lifespan.

Have questions about Furnace Repair, we can help!

Northwind Air Conditioning and Heat can help with Furnace Repair and regularly scheduled Heating System maintenance. Contact us and get the answers you need.