The heating system shuts off shortly after coming on. Feb 28, 2022
Heating equipment typically cycles for 10 to 15 minutes at a time. When the system starts up and shuts down again within a minute or two, this issue is known as short cycling. Short cycling has many causes – despite its cause, this issue causes damage to the HVAC equipment along with discomfort in the home, leading to higher heating bills and more frequent system repair needs.
1. Thermostat malfunction.
Faulty electrical connections, dirty temperature sensors, improper location of the device, or even an unlevel older mercury model are all issues that cause short cycling stemming from the thermostat. Gentle cleaning of sensors, recalibration, repositioning, or replacement may be used to solve these issues.
2. Improper thermostat anticipator calibration.
Some older manual thermostats have adjustable heat anticipators which warm up the interior of the thermostat in order to prematurely end a heating cycle. This is done in anticipation of residual heat in the ducts, allowing it to reach the living areas while avoiding overheating the space. Improper calibration of the anticipator can end heat cycles too early, causing short cycling. They can be adjusted, or the entire thermostat can be upgraded.
3. Overheating can be caused by poor airflow.
Dirty air filters and closed room vents restrict airflow through the furnace, which causes interior components to overheat. The furnace’s limit switch shuts down operation when internal temperatures are too high for safe operation. Replace the furnace filter and check all room vents to ensure they are fully open. A blocked flue pipe can also cause furnace overheating – blockages must be found and cleared not only to prevent short-cycling but possible carbon monoxide exposure in the home.
4. Faulty Flame Sensor In Furnace.
The flame sensor detects the presence of a flame when the furnace’s gas valve is open, working to prevent dangerous gas leaks and explosions. When it becomes dirty from soot, it may not detect the flame and the system shuts down shortly after starting as a safety measure. The existing sensor can be cleaned or replaced if broken, as corrosion is a common cause of damage to the component.
5. Faulty furnace draft inducer motor.
Many newer furnaces feature a draft inducer motor that exhausts combustion gases leftover from the prior heating cycle. If its air pressure switch does not detect proper airflow through the heat exchanger, it shuts the furnace down as a safety measure. This malfunction may be caused by an obstructed flue pipe or a fault in the pressure switch or the motor itself.
6. Oversized heating equipment.
When a heating system is installed that is too big for the home, it produces larger amounts of heat fast – this is not a good thing. Air heats up quickly, and the thermostat shuts down the heating cycle once the set temperature is detected. Repetitive short cycles wear out components, leading to higher energy consumption and more equipment breakdowns. Replacement is the only solution.
If you have any questions regarding your heating or cooling system, please contact us: 661 270 1961 http://www.acdaveheatingandair.com Lic#877683