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Why the Heater Is Shutting Off Too Early

cold-man-and-woman-in-parkasYou expect the central heating system in your house to run long enough to reach the temperature set on the thermostat. That’s its job. A heater should complete a full heating cycle that distributes warmth throughout the house, leaving few cold spots. But if your heater is shutting down after running for less than 15 minutes, or even less than 10 minutes, the house won’t get warm enough. A few rooms near the center of the house may be comfortable, but the rest of the house will be literally left in the cold.

The Culprit Causing Your Cold Home

What’s happening to the heating system? It’s a phenomenon called short-cycling, which is a symptom of many different problems with the HVAC system. Short-cycling on its own is a major concern because it:

  1. Fails to evenly heat the house
  2. Places extra strain on the heating system, leading to more repairs and a short lifespan
  3. Wastes large amounts of energy on repeating the start-up cycle

These are all negatives, but the underlying cause of short-cycling can be even worse. In most cases, you’ll need professional heater repair in South Burlington, VT to diagnose the short-cycling and have it repaired.

Here are a few of the more common causes of short-cycling.

  • Clogged air filter: We hold this as a maxim—when anything seems wrong with a forced-air heater (furnace, heat pump) always check to see if the filter needs to be changed. Short-cycling is one of many troubles a clogged filter can cause; it traps too much heat inside the system, which will cause it to cycle down to avoid overheating.
  • Blocked air vents: Airflow issues, in general, can lead to a system overheating, and room vents that are blocked or closed will cut down on airflow. Make a check of the rooms in the house to see that all vents are cleared of obstructions and open.
  • Leaking refrigerant: If you have a heat pump or dual fuel system, refrigerant leaks can trigger short-cycling. Low refrigerant levels will put the entire heat pump in jeopardy of overheating and burning out. 
  • Miscalibrated thermostat: The thermostat may be falsely detecting higher temperatures in the house, which will cause it to prematurely shut down the heater. Professionals can recalibrate the thermostat to fix this. 
  • Oversized system: Is this your first winter with this heater? Then the problem may be that it was sized incorrectly when installed so it’s too powerful for your house. Yes, too powerful is a problem. The rapid raising of temperature will cause the heater to shut off early, but the uneven heating left behind will force it to turn right back on again and keep repeating the cycle. The only way to fix this is to replace the heater—and make sure experienced professionals do it so the system is sized right. 

If you can’t locate a simple reason for your short-cycling heater, such as a clogged air filter or blocked vents, please leave the investigation and repair work to our professionals. There are many more possibilities than what we listed here, and we’ll see that we find the right solution for your home heating.

Red Rock Mechanical, LLC serves Northwest Vermont and Northeast New York. Call us for heating repair—we offer 24-hour emergency services.

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