We use cookies to enhance your experience on our website. By clicking '' or by continuing to use our website, you are agreeing to our use of cookies. You can change your cookie settings at any time.

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.

How to Troubleshoot Your Heat Pump: Tips and Tricks to Keep Your HVAC Systems Running Smoothly

Heat pumps are great HVAC systems because they can both heat and cool your home, without relying on burning fuels or expensive electric heating. Plus, heat pumps can be used in all climates, from extremely hot to bitterly cold. Unfortunately, their ability to perform multiple functions also means that your heat pump can face both heating, cooling, and some other issues. Here, we’ve outlined some of the most common heat pump problems, so you’ll know exactly what to do if your heat pump isn’t working.

Heat pump is frozen

It’s possible that your heat pump might freeze over in the winter season, especially if temperatures tend to significantly drop where you live. Your heat pump’s outdoor coil is typically 10 to 20 degrees colder than the air outside, so the unit freezing over can happen even if the temperature isn’t below freezing.

The good news is, periodic ice build-up or frost on the outdoor coil is perfectly normal. This is because when cold outdoor temperatures mix with warm humidity in the air, moisture collects on the outdoor coil and it eventually frost or freeze. To combat this problem, your heat pump has a built-in defrost cycle. The defrost control has two sensors: one inputs the outdoor temperature and one inputs the coil temperature to the defrost control. After that, a microprocessor control determines the correct defrost cycle to utilize, which then clears the frost from your coil to address the issue.

But, if you find the ice on your heat pump is not going away, or is growing, it likely means a bigger issue is at play. A frozen heat pump could be caused by low refrigerant levels, faulty defrost controls, or a faulty sensor. Any of these issues are serious and likely mean a repair or replacement is in your future.

What you can do

It’s important you always monitor your heat pump when cold weather arises for any visible signs of frost or ice. If you suspect your heat pump is frozen, wait a few hours without doing anything to see if the ice melts and the unit defrosts itself. If the problem isn’t subsiding, call in an HVAC professional to troubleshoot.

Heat pump not heating

Your heat pump might struggle to provide heat in the winter season. When it’s cold, your heat pump works to extract heat from the air outside, then uses refrigerant to carry that heat through the system and deposit it into your home, until your home reaches the temperature you want. If your home doesn’t feel like it’s heating up in the winter, your heat pump might be experiencing an issue completing its cold weather task.

What you can do

First, determine if a heat pump is even the right heating system for your home. While heat pumps are capable of heating in extremely cold temperatures, if you live in a place where winters are consistently below freezing, your heat pump is likely working overtime when it’s required to heat, which could be the source of your issue. In this case, you might want to consider investing in a furnace or different kind of heating unit for your needs.

If consistently cold temperatures aren’t causing your heating issues, try checking your thermostat settings, and making sure your unit is powered on. If neither of these things work, contact an HVAC professional for help, because the issue is likely caused by an improperly sized unit, low refrigerant, or something else only a professional will be able to diagnose and fix.

Heat pump not cooling

One misconception about heat pumps is that they only perform a heating function. Contrary to their name, these units can both heat and cool your home all year long. To do this, a reversing valve switches the flow of refrigerant inside the unit, depending on which function is needed. If your heat pump is having trouble cooling your home when it’s hot out it could be the cause of a different part failure, low refrigerant levels, or something simpler like a dirty filter.

What you can do

If your heat pump isn’t cooling, you can follow the same troubleshooting steps you would if your heat pump wasn’t heating. This includes making sure your thermostat is on and set to the correct temperature and checking that your unit hasn’t accidentally been switched off. If this doesn’t work, contact an HVAC professional to further troubleshoot.

Heat pump not turning on or off

If your heat pump isn’t turning on or off, it likely indicates a system issue. Your thermostat controls your heat pump, so if the heat pump isn’t turning on or off it could be because your thermostat isn’t able to relay that message to the heat pump. Alternatively, a power loss, or electrical problem could be causing the issue.

What you can do

The first step to take once you realize your heat pump isn’t turning on or off is to have your power source checked by an HVAC professional. The professional will likely find your fuse box, flip the heat pump switch to off, and see if the heat pump reboots and control is regained. This task must be performed by a professional, because it’s possible it could blow a fuse in your home. You’ll also need to call in an HVAC technician if you suspect any electrical issues.

Heat pump making unusual noises

If you hear strange noises coming from your heat pump, it’s likely a sign there’s a problem. These strange, not normal noises include, but aren’t limited to, banging, screeching, rattling, buzzing, grinding, or gurgling. If you hear any of these sounds, extremely loud sounds, or prolonged sounds coming from your heat pump, it could be a sign of electrical issues or system failure.

What you can do

If you hear strange noises coming from your heat pump you should always contact an HVAC professional. In most cases, getting to the root cause of any issue related to unusual noises requires examining parts of the system and the electrical work. You’ll need to get help from an HVAC professional for both your safety and the safety of your heat pump.

Heat pump troubleshooting: When to call a professional

In some cases, like when you hear unusual noises coming from your unit, you need to call in an HVAC professional right away. For other situations we mentioned, there are a few safe troubleshooting tips and tricks you’re able to perform yourself. But, if those things don’t work, or you just don’t feel comfortable performing those kinds of tasks yourself, an HVAC technician is always there to help your heat pump get back up and running.

Is your HVAC system still experiencing issues?

Your local Trane dealer can help.

Maintenance Tips

A healthy HVAC system can last longer and save money. Maintain your system with these tips.

Owner’s Manual

Learn more about your product, like its technical specs and innovative technology.

Warranty & Registration

After getting a new system, be sure to protect it with a warranty.

Contact a local dealer

Dealers can answer questions, help you find the right products for your home, and repair your system.

We’re here to help

Connect with our Customer Care team about your products, warranties, and dealer concerns.

Available Monday – Friday from 7am to 5pm CST


A phone