Heat pump not working: simple checks to run before calling a technician

Quick Answer

Identify if your home feels cold or if the indoor unit remains silent when the heat pump is not working. Green Writer wrote this page for readers who need to troubleshoot common mechanical failures and verify that the outdoor condenser fan is spinning freely.

A heat pump requires a steady flow of refrigerant, which is a fluid that carries heat, rather than a simple gas supply to function correctly.

Common reasons for a heat pump not working

A heat pump often fails to work due to a power loss, a thermostat setting error, or a tripped circuit breaker. You can confirm the cause by checking your electrical panel, verifying the thermostat display, and ensuring the outdoor unit has a clear path for airflow.

Mini split troubleshooting steps

• Check the thermostat display to see if the system is receiving a call for heat or cooling.
• Verify that the circuit breaker is in the on position within your main electrical panel.
• Test the power supply to the indoor unit to confirm electricity reaches the evaporator coil. Power supply is the electrical source that provides the energy needed to run the heat pump components.
• Identify if the ac heat pump not working status stems from a tripped high-pressure switch.
• Confirm the emergency heat setting is active if the primary heat pump fails to produce warmth.

Emergency heat provides a backup for your home

Emergency heat is a secondary heating system that activates when the primary heat pump cannot provide enough warmth. It typically uses electric resistance coils to generate heat quickly. Knowing this allows you to stay warm while waiting for a technician to repair your main unit.

Troubleshooting your mini split system

Emergency heat uses electric resistance coils to generate warmth when the heat pump fails. This backup system changes the heat source from the outdoor compressor to internal heating elements. You can understand how a heat pump works to see if the system switches to this mode during a malfunction.

How do I check if the power supply to the unit is active?

You can check if the power supply to the unit is active by verifying the circuit breakers and local switches. A tripped breaker or an off switch prevents the system from receiving electricity. Confirming these components are engaged ensures the unit receives the necessary current to begin its operation.

Locate the main electrical panel and the outdoor disconnect switch to confirm current flow.

Power supply checklist

1. Check the electrical panel for any tripped breakers that need to be reset to the on position.
2. Verify the outdoor disconnect switch is in the on position to confirm the circuit is closed.
3. Look for a tripped internal breaker if the air conditioner heat pump not working issue persists despite the main power being on.
4. Test the thermostat display to see if it shows a power status light or a blank screen.

Actions for a unit that won't start in freezing weather

Extreme cold can cause the unit to shut down to prevent damage. Reset the system by turning the disconnect switch off and on again. Check the outdoor unit for ice buildup that might block airflow or sensors.

Power supply checks for the pump

Signs that a heat pump is failing include a compressor that makes loud grinding noises, a refrigerant system that leaks fluid, or a unit that fails to move air. You might also notice inconsistent temperatures in different rooms or a complete loss of airflow from the vents.

Ductless heat pump symptoms

• A compressor making a loud clicking sound often indicates internal mechanical failure.
• Refrigerant levels drop when the system leaks fluid from the coils.
• The indoor unit produces weak airflow if the blower motor fails.
• A household experiences a heat not working heat pump issue when the thermostat remains unresponsive.
• Ice buildup on the outdoor coils suggests a restricted airflow path or low refrigerant.

Warning signs for a ductless heat pump

Ductless units show failure through specific physical cues. Check if the indoor head unit produces a clicking sound or if the fan motor stops spinning entirely. Inspect the outdoor unit for frost buildup or oil stains, and compare air to water heat pumps to identify potential refrigerant line leaks.

Is the outdoor unit blocked or obstructed?

An obstructed outdoor unit prevents the heat pump from moving air efficiently, which causes the system to overheat or cycle off. You should ensure that no tall grass, debris, or structures block the airflow around the unit. Clear space around the cabinet helps the system maintain steady operation.

Clear leaves and snow from fins

Check the area around the base of the unit for piles of leaves or snow. These items can clog the fins of the evaporator coil, which is the component that exchanges heat with the outside air. If the coil remains dirty or covered, you should compare heat pumps with other heating to see how the system performs.

Checking for obstructions and low refrigerant levels

Verify that there is at least two feet of clearance on all sides of the machine. If you see physical barriers like bushes or fences, move or trim them to reset the airflow path. Proper clearance helps the fan move air through the system without resistance.

Check for damage or low refrigerant

Inspect the evaporator coil for signs of physical damage or heavy buildup. If the unit remains clear but still fails to heat, the system might have low refrigerant. A technician must check the refrigerant pressure to confirm if a leak exists.

Checking for clogs in the heat system

Check the air filter by removing it from the intake housing and inspecting the surface for dust or debris. A clogged filter restricts airflow and causes the heat pump to work harder or stop running. If you cannot see light through the filter material, the filter requires a replacement, so learn how this efficient appliance works to ensure optimal performance.

Air filter inspection guide

1. Locate the air filter slot on the indoor air handler or furnace unit.
2. Remove the air filter by sliding it out of the metal frame or plastic housing.
3. Hold the air filter up to a bright light source to check for clear visibility.
4. Replace the air filter with a new one if the mesh appears grey or blocked.

Methods to inspect air filters

Visual inspection works best for identifying heavy dust buildup or pet hair. You can also perform a pressure test by feeling for resistance when blowing air through the filter. If the air feels restricted, you should compare heat pumps with furnaces to determine if the filter needs a swap to restore system flow.

Perform these simple checks if your heat pump is not working

Resolving a heating failure requires a systematic review of your system's current status and basic operational requirements.

Troubleshooting checklist

1. Locate your heat pump's model number and installation date. Find these details on the unit's nameplate or your original installation paperwork. Having this information ready ensures you provide the correct data to a technician.
2. Verify that the thermostat is powered and set correctly. Check that the display is active and the target temperature is higher than the current room temperature. If the screen is blank, check the power supply.
3. Inspect the outdoor unit for debris or obstructions. Clear away leaves, snow, or dirt from around the unit. Ensure there is at least 60cm of clear space around the exterior housing.
4. Check the circuit breaker and main power switch. Look at your electrical panel to see if the heat pump breaker has tripped. Flip it back to the on position if it has moved.
5. Contact a qualified technician for a professional inspection. Call a licensed HVAC technician if the unit remains unresponsive after these checks. Provide them with the model number you located in the first step.

Frequently asked questions