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Your Comfort is Our Priority!

Emergency Service



Heat Pump Won’t Switch Modes? Here’s Why!

Monday, December 23rd, 2019 at 11:00 am

logo-of-sun-and-snowflakeWhen it comes to the weather in Florida, it’s fairly predictable—it’s always hot, right?

Well, if you’ve lived in our area for even just a year or two, you know that’s not always the case. Sure, we don’t get snow in the fall and winter like other states along the east coast. But when temperatures drop, the contrast is enough to make us very thankful for our heating systems.

One of the most common types of heaters used within our climate is the heat pump system—because we do have mild winters but very hot summers, the refrigerant process of a heat pump is the perfect year-round, 2-in-1 HVAC system.

If you already have one in your home, you’re using one of the most efficient heaters you can find! Though, if you’re reading this particular blog post, it likely means you found it won’t switch to heating mode. Why is this happening?

Refrigerant Flow

To answer this question, we first need to explain how refrigerant works within your heat pump system. When in heating mode, the refrigerant circulates through the inside and outside components of the system to absorb heat from the outdoor air and bring it in. When it’s switched to cooling mode, a reversing valve activates to help that refrigerant flow in the opposite direction.

There are components called check valves that help the refrigerant avoid some parts it would otherwise pass through in the opposite mode. In order to switch from cooling to heating mode this winter, your heat pump relies on these valves in addition to another part called a sliding cylinder to do the job. Read on as we describe these components, and what can go wrong with them, in more detail.

  • Reversing Valve: This valve is essentially the main component responsible for the refrigerant changing direction. If it’s stuck or broken, then your heat pump will indeed struggle to switch modes, if it’s able to at all.
  • Check Valve: This is meant to automatically stop back-flow (reverse flow) of refrigerant when the line reverses direction. Check valves are self-automated, however, they can get stuck. When this happens, it prevents your heat pump from effectively switching modes.
  • Sliding Cylinder: Once you switch your heat pump into a different mode using your thermostat, the sliding cylinder is supposed to initiate the process. Yes, you reversing valve is responsible for enabling the refrigerant in the heat pump to reverse into heating mode or cooling mode, but the sliding cylinder is vital to this process. If it breaks down or gets stuck, then your heat pump simply cannot switch modes.

Lastly, your heat pump problem may not be a problem with the actual system or these above mentioned components at all, but rather the thermostat. Whether it’s faulty wiring or issues with the programming of the thermostat, this small but mighty component may be to blame.

All this said, we discourage you from ever trying to diagnose or repair a heater problem on your own. Please give our team a call if you suspect something is amiss!

Need St. Augustine, FL heat pump services? Contact Climate Masters. Serving St. Johns County since 1988 with quality, hometown service.

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