Heat pumps are versatile HVAC systems that provide both heating and cooling for residential and commercial spaces. In this article, we’ll explore two primary types of heat pump and address common symptoms and troubleshooting steps for when your heat pump won’t turn on. 

Whether you’re experiencing constant running, mode switching issues, or short cycling, we’ll help you diagnose and resolve the problem.

Types of Heat Pumps

Heat pumps work both as a heating and air conditioning system which makes them very versatile and a great investment for homeowners in the mild climate of Lafayette. There are two main types of heat pumps – air source and ground source heat pumps.

Graphic illustrating mechanics of an air source heat pump.

As the name implies, air source heat pumps work by taking heat from the outdoor air and transferring it indoors during the winter to warm your home. Then, in the summer, they do the opposite, taking heat from inside and pushing it outdoors to cool your home. They’re like two-for-one deals, acting as both heaters and air conditioners. They’re pretty easy to install and more budget-friendly, which makes them a popular choice for many households.

Three dimensional rendering of home with ground source heat pump.

Now, ground source heat pumps, also called geothermal heat pumps, tap into the steady temperature underground to keep your home comfy all year round. It involves burying pipes underground to circulate fluid that absorbs heat from the ground in winter and releases it in summer. They might cost a bit more upfront and require some digging, but they’re super efficient and can help you save big in the long haul. 

Which Kind of Heat Pump is Common in Louisiana?

In Lafayette, Louisiana, air source heat pumps are generally more popular due to their affordability and ease of installation. The region’s mild climate makes air source heat pumps effective for providing both heating and cooling throughout the year, leveraging the temperature differences between outdoor and indoor air. Additionally, the relatively flat terrain and soil conditions in Lafayette might make ground source heat pump installations more challenging and costly. Therefore, many homeowners in Lafayette opt for air source heat pumps as a practical and cost-effective solution for their heating and cooling needs.

How to Troubleshoot Why Your Heat Pump Won’t Turn On

First and foremost, it’s helpful to address the symptoms you’re experiencing with your heat pump in order to narrow down the reasons it won’t turn on. Whether your unit is short cycling, constantly running, or not turning on at all will influence which troubleshooting methods you’ll want to use.

  • Constantly running
  • Not running
  • Not switching modes
  • Short cycling

Heat Pump Constantly Running:

  • Dirty or clogged air filters restricting airflow, causing the system to work harder.
  • Refrigerant leaks leading to insufficient cooling or heating capacity, causing the system to run continuously to try to reach the set temperature.
  • Improper thermostat settings, such as setting the temperature too high or low, resulting in the heat pump running non-stop to meet the desired temperature.
  • Undersized heat pump unable to effectively heat or cool the space, causing it to run continuously to maintain comfort levels.

Heat Pump Not Running:

  • Power supply issues, such as tripped circuit breakers, blown fuses, or a disconnected power source preventing the heat pump from receiving electricity.
  • Faulty thermostat not sending the signal to the heat pump to turn on.
  • Defective capacitor or relay preventing the compressor or fan from starting.
  • Motor or compressor failure, causing the heat pump not to initiate its operation.

Heat Pump Not Switching Modes:

  • Thermostat issues, such as a malfunctioning mode selector or incorrect settings, preventing the heat pump from switching between heating and cooling modes.
  • Reversing valve malfunction, which is responsible for changing the flow direction of refrigerant to switch between heating and cooling modes.
  • Electrical or wiring problems disrupting the signal between the thermostat and the heat pump, preventing mode changes.

Heat Pump Short Cycling:

  • Improperly sized heat pump cycling on and off frequently due to quickly reaching temperature set points.
  • Restricted airflow caused by dirty or blocked air filters, ductwork issues, or obstructions around the outdoor unit, leading to overheating and frequent cycling.
  • Refrigerant leaks or low refrigerant levels causing the system to cycle frequently as it struggles to maintain proper pressure and temperature levels.
  • Faulty thermostat or sensor misreading indoor temperature, resulting in frequent cycling as it tries to maintain the set temperature.

Technician checking to see why heat pump won’t turn on.

Frequently Asked Questions

How do I reset my heat pump?

If your heat pump does not have a reset button, locate the power switch or breaker for the unit. Turn it off and wait for two to three minutes before turning it back on. This action will allow the system to reset and may resolve minor issues.

What would cause a heat pump not to kick on?

Several factors could prevent a heat pump from kicking on, including a tripped circuit breaker, a blown fuse, a malfunctioning thermostat, or a fault in the heat pump’s components such as the compressor or fan motor.

What is the most common problem with heat pumps?

One of the most common problems with heat pumps is improper airflow, often caused by dirty air filters, obstructed ducts, or blocked outdoor units. This issue can lead to reduced efficiency, inadequate heating or cooling, and increased wear on the system components.

How long do you cut off electricity to reset the heat pump?

When resetting a heat pump by cutting off electricity, it’s typically recommended to leave it off for at least 30 seconds to ensure a complete reset of the system.

If an electric heat pump won’t turn on, but the thermostat and power to the house/unit are both working, what could be the problem?

If an electric heat pump won’t turn on despite the thermostat and power to the house/unit working, potential issues could include a faulty relay, capacitor, or compressor, as well as wiring problems or sensor malfunctions.

Heat pump cooling but not heating, reversing valve is good.

If your heat pump is cooling but not heating, and the reversing valve is confirmed to be functioning properly, it could indicate issues such as low refrigerant levels, a malfunctioning compressor, or a faulty thermostat.

Heat pump technicians at Lee’s in Lafayette standing in front of their office building.

Need an Extra Hand? Call Lee’s in Lafayette!

These are a great starting point to help you understand why your heat pump won’t turn on, but of course, this list is not an end all be all. Heat pump issues can be 

If you’ve tried to make the fixes yourself and your heat pump still isn’t heating adequately, it’s time to enlist the expertise of Lee’s AC. Our experienced technicians will perform a comprehensive inspection to diagnose the issue accurately and recommend the necessary repairs or replacements.

At Lee’s AC of Lafayette, we understand the importance of a functioning heat pump for your comfort and well-being. Don’t delay — contact us today for reliable solutions and exceptional service. Let us help you stay warm and comfortable throughout the winter season.

Leave a Reply