Year-End: The Most Common Heat Pump Problems We Fixed in 2025

As heat pumps continue to replace oil, gas, and propane systems across Massachusetts, 2025 was another busy year in the field. More systems means more real-world data and after thousands of service calls, a few patterns became impossible to ignore.

This isn’t a list of rare failures or horror stories. These are the most common heat pump problems we actually fixed in Massachusetts homes this year, what caused them, and what you can learn from them heading into the next heating season.

Icing and Defrost Issues (That Weren’t Actually Problems)

By far the most frequent call we got in 2025: “My outdoor unit is covered in ice or blew cool air for about a minute…is my heat pump failing?”

In most cases? The system was working exactly as designed.

Cold-climate heat pumps regularly enter defrost mode during freezing, humid New England weather. If you’re not familiar with the process, seeing frost or ice buildup can look alarming. But it’s normal. The unit will periodically reverse cycle to melt that ice off, then go right back to heating your home.

The real issues we found were usually blocked airflow—snow drifts piled against the unit, overgrown shrubs, or deck skirting too close to the condenser. We also corrected controls or sensors on a handful of systems where defrost cycles weren’t completing properly.

The takeaway? Ice on the outdoor unit isn’t automatically a problem. Persistent ice that never clears is.

Additionally that slightly cooler air? That likely means your unit is in defrost mode. This is normal!

Poor Performance Because of Airflow Restrictions

Another recurring theme in 2025: systems that were technically fine, but starved for air.

We saw dirty or clogged filters more times than we can count. Furniture (we know you love putting that bookcase under the unit…but don’t do that!) blocking ductless heads. Undersized or collapsed ductwork on ducted systems that nobody noticed until the heat pump exposed the problem.

Heat pumps rely on steady, unobstructed airflow. Even small restrictions can dramatically affect comfort and performance. Once we restored airflow and corrected basic setup issues, or rebalanced ducted systems that were fighting themselves, the problems disappeared.

If there’s one thing homeowners should take from this: change your filters. Set a reminder. Write it on the calendar. It matters more than you think.

Backup Heat Running Too Often

We saw this most often during the January cold snaps.

Backup heat—whether it’s electric resistance strips or your old furnace—was kicking in more than expected. Not because the heat pump “couldn’t handle the cold,” but because the home was losing heat faster than the system could replace it.

Poor insulation, significant air leakage, and systems that were sized for leaky homes instead of addressing the envelope first—all of these forced backup heat to run constantly. In some cases, we adjusted control settings and lockout temperatures. In others, we recommended insulation and air sealing improvements, then came back to recalibrate the system after the weatherization work was done.

If your backup heat is running constantly, the issue is usually the house, not the heat pump.

Installation-Related Issues (Almost Always Fixable)

Not all problems show up years down the road. Some appear early—and most are fixable.

We saw refrigerant charge adjustments that needed fine-tuning, drain line routing issues that caused condensate problems, and minor wiring or communication errors between the thermostat and equipment. These weren’t catastrophic failures. They were details that got missed during the initial setup.

Heat pumps are precise systems. Proper commissioning matters just as much as the equipment itself. Once we commissioned systems to manufacturer specs and corrected those install details, everything ran smoothly.

Also if you did whole home heat pumps but haven’t done your insulation yet, this is critical! The heat pump designs for a Mass Save whole home heat pump assume you have or will properly weatherize your home to program standards. If you haven’t, the installed heat pumps will not work properly leading to discomfort and potentially higher than necessary electric bills!

Thermostat and Control Confusion

Smart thermostats are great, but they often get set up wrong for heat pump logic (minor mistakes that even our own installation techs occasionally have made can lead to a service call!).

We found aggressive setbacks that forced backup heat to engage unnecessarily. Incorrect system types selected in the thermostat settings. Homeowners manually overriding efficient operation because they didn’t understand how the system was supposed to behave.

Once we reconfigured thermostats for heat pump behavior and explained how steady-state operation works, those problems went away. Heat pumps don’t behave like furnaces. Big temperature swings and aggressive setbacks fight against how they’re designed to operate. The controls need to match the technology.

Also if you call saying your electric bill is higher than expected one of the first questions will be whether you “set it and forget it” or if you are turning the temperature up and down for different times of the days. Doing the latter can have a significant impact on your utility bill in the cold months and it’s not how heat pumps should be operated!

What These Problems Had in Common

Here’s what stood out from 2025: most issues were not equipment failures. Many problems came down to education gaps or home conditions. Insulation, airflow, and controls mattered just as much as the heat pump itself.

When those pieces are addressed correctly, heat pumps performed extremely well, even during Massachusetts’ coldest weeks.

Why This Matters Going Into 2026

As adoption keeps accelerating, the difference between a great heat pump experience and a frustrating one comes down to design, installation, and whole-home thinking.

More homeowners are starting to realize they need contractors who understand heat pump behavior in New England winters, who look at the building envelope and not just the equipment, and who know how to integrate insulation, controls, and system design into one coherent plan.

That’s the approach we take every day at Endless Energy.

Frequently Asked Questions: Common Heat Pump Service Calls

Are icing problems common on heat pumps in Massachusetts?
Yes. Ice buildup during winter is often normal due to defrost cycles. The issue is persistent ice that never clears or blocks airflow.

Why did my heat pump use backup heat so often in 2025?
Frequent backup heat use is usually caused by insulation issues, air leakage, or control settings — not because the heat pump can’t handle cold weather.

Do heat pumps require different thermostat settings than furnaces?
Yes. Heat pumps work best with steady temperatures. Large setbacks often trigger backup heat and reduce efficiency.

Are most heat pump problems equipment failures?
No. Most issues we fixed in 2025 were related to airflow, controls, installation setup, or home heat loss rather than failed equipment.

Who should I call if my heat pump isn’t performing well?
A contractor experienced with Massachusetts heat pump systems — like Endless Energy — can diagnose whether the issue is the system, controls, or the home itself.

Final Thought for Massachusetts Homeowners

If your heat pump struggled in 2025, it doesn’t automatically mean the system was a mistake. In most cases, the solution wasn’t replacement—it was fine-tuning, education, or addressing the home itself.

Going into the new year, the smartest move is a proactive checkup. Catching small issues early keeps your system comfortable, efficient, and reliable for the long run.

If you want help making sure your heat pump is set up for success in 2026, schedule a heat pump service appointment or a new heat pump consultation with Endless Energy!