Why Does My Heat Pump Start Then Stop?

The Top Reasons for Heat Pumps Short-Cycling 

If you have a heat pump and have noticed it shuts off shortly after being turned on, it may have an issue known as short-cycling. Short-cycling isn’t just a nuisance — it can lead to discomfort, reduced energy efficiency, and higher energy. But what causes short-cycling, and what can you do to prevent it?

Below, the HVAC experts at Total Air discuss the leading causes of heat pump short-cycling and what homeowners can do to minimize the risk of this issue.

How Does a Heat Pump Work?

Heat pumps transfer heat from one place to another using a refrigeration cycle. While in heating mode, the system extracts heat from either the ground or outside air, transferring it indoors to warm your home.

This process is achieved by compressing refrigerant gas, which heats as it becomes pressurized, then passes through a condenser where the heat is released indoors. The refrigerant then circulates back to the outdoor unit, where it expands and absorbs more heat from the outside.

In cooling mode, this process is reversed as heat is extracted from your indoor air and expelled outdoors.

Using ambient heat sources rather than generating heat, heat pumps are an energy-efficient method for heating and cooling, providing year-round comfort that’s environmentally friendly and cost-effective.

Why Does My Heat Pump Keep Short-Cycling?

There are many reasons why your heat pump may short cycle, the most common being:

Thermostat Issues

If your thermostat is installed in a place that gets direct sunlight or if the system itself is faulty, it could read the incorrect temperature, thinking your home is hotter than it is. This can cause short-cycling as your thermostat tells your heat pump that your home is already at the desired temperature.

Dirty Filters

One of the simplest causes of short-cycling is a clogged air filter. When your filter becomes too dirty, it can cause your heat pump to overheat and shut down. Cleaning or replacing your air filter regularly can help prevent this, allowing you to regain total HVAC functionality.

Refrigerant Issues

Heat pumps rely on refrigerant to complete their heating and cooling cycles. If your system’s refrigerant levels are too low, it could cause it to underperform and short-cycle. This issue can also present if your system has a refrigerant leak.

Note: Refrigerant requires specialized tools and training to handle properly. If you suspect a refrigerant leak in your unit, contact a professional for heat pump repair rather than attempting to resolve it on your own.

Incorrect Sizing

In some cases, your heat pump may not be the correct size for your home. If it’s too large for your space, it can warm or cool the home too quickly, causing it to shut off when it reaches the set temperature. When this happens, the best solution may be a heat pump replacement.

When To Call a Professional To Check Your Heat Pump

While some short-cycling issues can be resolved through DIY troubleshooting, others require the skill and attention that only a trained professional can provide.

Look out for these signs that it’s time to contact an HVAC professional:

• You suspect electrical issues are causing your short-cycling problems.
• You’ve tried changing the filter, and it continues to short cycle.
• Your thermostat is faulty.
• You think your heat pump is the incorrect size for your home.
• You need help replacing the refrigerant or notice a refrigerant leak.

Why You Should Call Total Air

Are you tired of dealing with persistent short-cycling issues in your heat pump? Total Air offers 24/7 heat pump repairs to regain total functionality quickly.

With over 60 years of experience, we’re uniquely capable of diagnosing and fixing any problems with your HVAC equipment.

Schedule heat pump repair in Dallas by calling 972-881-0020 today.