HVAC Troubleshooting

Follow our interactive troubleshooting guide to find answers to your system’s problems.
Choose from a selection of common HVAC issues or pick your product for help with fixes you can try yourself.

Heat Pump Reversing Valve Basics

Heat pump systems are gaining in popularity throughout the United States as homeowners look for sustainable and affordable heating and cooling solutions. If air source heat pumps are new to you, you may wonder how one unit can both cool and heat your home.

What is a heat pump reversing valve and how does it work?

The HP reversing valve is a small component in a heat pump with a big job. It’s a brass valve located at the outside unit and connects to the refrigerant lines inside the condenser unit cabinet. It’s also connected to the thermostat and controls the refrigerant flow. When it’s in cooling mode, an electric heat pump uses the refrigeration cycle just like a central air conditioner does to cool your home.

A refrigeration cycle has a hot coil and a cold coil. The hot outdoor coil is called the condenser coil, and the cold coil is called the evaporator coil. In the summertime, the air is blown across the cold indoor coil (the evaporator) inside your home. That cooled air is what keeps you comfortable in the summer heat.

But in the fall, the heat pump can switch to heating mode to heat your home. When the thermostat sends a signal that it’s time to heat, the reversing valve reverses the flow of refrigerant. This makes the coil inside your home become the hot coil (the condenser), so that now as the air in your home blows across the coil it is heated up, keeping your house warm.

Signs there may be a problem with the reversing valve

There are several indications that there may be a problem with your heat pump reversing valve. Keep in mind that other issues can cause the same symptoms, so your best bet is to call an HVAC professional for help.

What to look for:

Heat pump not heating
The heat pump not cooling
The unit is stuck in one mode
Heat pump is making strange noises

How to unstick a reversing valve on a heat pump

Occasionally, the reversing valve can become stuck, not allowing the heat pump to switch from heating mode to cooling mode or vice versa.

It is uncommon for this valve to get stuck. To see if this is the problem, you will need to contact an HVAC technician. Don’t try to troubleshoot this issue yourself - you could damage the valve and cause a refrigerant leak.

When to call for heat pump repair

If your attempts to unstick the reversing valve didn’t do anything and your heat pump is not heating or cooling as it should, it’s time to call for heat pump repair. If possible, call the HVAC company that installed the unit, especially if it is still under warranty. You also want to make sure you hire a company with lots of experience with heat pump systems.

If the issue is the reversing valve, you may be wondering about heat pump reversing valve replacement cost. The average cost to replace the reversing valve is between $400-$700. Your costs will vary based on where you live and how many HVAC companies serve your area, among other things.

Check out our blog on average heat pump repair costs for more information.

Prevent problems with heat pump maintenance

A clogged or dirty heat pump air filter can cause all sorts of problems. You can prevent many common issues by keeping up with air filter maintenance. This means changing standard filters every 30-90 days. If you have an air purification system, it can mean replacing the air cleaner insert every 6 months or cleaning the unit.

Trane heat pumps are high-quality heating and cooling systems that function best with regular maintenance checks. Schedule heat pump service visits for each fall and each spring.

Consider opting into Trane Diagnostics

Opt into Trane Diagnostics for peace of mind. Through the Trane Home App, you can give your dealer remote monitoring capabilities of your heat pump system. Your Trane smart thermostat sends data in real-time to your dealer, alerting them to any issues, sometimes before you even realize there’s a problem.

They can run heat pump troubleshooting tests to narrow down or even pinpoint the problem. In some cases, they may be able to fix the problem remotely. In this situation, you would give them one-time dealer remote access (DRA).

If they need to schedule on-site heat pump repair services, the technician will arrive with the knowledge gained from remote access. This results in shorter service calls and ensures the technician has the proper replacement parts.

Anne Fonda, Content Writer at Trane Technologies

A Content Writer with Trane Technologies, Anne Fonda researches topics and writes for Trane® and associated residential HVAC brands. She works in collaboration with Trane Technologies subject matter experts, offering easy-to-understand, informative content on complex topics. Her goal is to help consumers make informed decisions on the products and services they need.

She has written for HVAC and other service provider websites for over 16 years. Before transitioning to web content writing, Anne had a 14-year stint as an award-winning journalist. She graduated cum laude from the University of Missouri-Columbia School of Journalism. When she’s not working, Anne enjoys playing word games, reading, gardening, spending time with family, and visiting gardens and museums.

Expert review by Kimberly Sexton, Senior Systems Engineer