If the outside fan doesn't run at all in
The outdoor fan for a heat pump should spin constantly during normal operation. It may even start spinning during the defrost cycle. If the fan won't move at all, there is a problem.
A heat pump needs the fan to work correctly. If it's not working, there could be a few reasons why. One possible cause is that debris has built up inside the unit and blocked the fan blades from moving. The outside unit can easily get dirty or blocked with debris because of its location.
The only benefit to running the fan is getting the warm air moved around a bit. If it's not super uncomfortable there's no need to circulate the air. It won't make a huge difference so it's totally up to how comfortable you are already.
While it may seem strange for the outside heat pump fan to run in heating mode, it's an important part of the system's operation. It plays a large role in the heat exchange process and makes sure that your system can extract heat properly from the outdoor air. Even in colder conditions.
The heat pump fan typically runs continuously during the winter, even when the system is in heating mode. Its primary function is to pull in the outdoor air and circulate it over the outdoor coil, where heat exchange takes place.
Why Is My AC Fan Not Spinning? In short, common issues that can cause an air conditioning unit fan to stop spinning are electrical issues, problems with the capacitor, contactor issues, a burnt out air conditioner motor, a broken fan belt, or clogged air filter.
Choose "AUTO" for energy savings and "ON" if you want constant air circulation or improved air filtration. Temperatures can soar or plummet depending on the time of year.
During the winter months it is best to allow your heat pump to run at a lower fan setting and spread heat out more evenly over a longer period of time. The reason for this is two fold: Maintaining temperature over a longer period of time is more efficient than getting a room to temperature quickly.
It's Defrosting
To protect the outdoor coils from freezing up in the winter, heat pumps go through a defrosting period every hour or so in which they are truly blowing out cold air. This defrosting period only lasts a few minutes and should not affect the overall temperature of your home.
The outside unit may not run if it's shut off or the safety switch is engaged. Worn parts, like fan motors or contactors, can prevent the unit from turning on. Debris inside or outside of an AC unit can keep it from running properly. If a bad compressor is to blame, you'll need to install a new cooling system.
This action temporarily warms up the outdoor coil and melts the frost from the coil. In this defrost cycle, the outdoor fan is prevented from turning on when the heat pump switches over, and the temperature rise of the outdoor coil is accelerated and increased.
Does The AC Fan Outside Always Run? The answer to this is no. The AC fan does not run non-stop. It's intended to cycle on and off, depending on the needs of the HVAC unit.
Heat Pumps Don't Actually Stop Working
Contrary to popular belief, heat pumps don't ever stop working when it's cold. These systems are built to withstand frigid weather, operating at 100% efficiency even down to -13 degrees Fahrenheit.
Leaving the fan running reduces wear and tear on the motor since it's not starting and stopping repeatedly. It's also beneficial to boost filtration, but leaving it on this setting has more drawbacks than benefits. When it runs nonstop, the fan consumes more energy, and the air filter needs frequent replacement.
To put it simply: Yes, the outside fan should run when your heat pump is in heating mode. Here's why. The outside fan is responsible for the transfer of heat from the outdoor air to the refrigerant coils inside the outdoor unit. Even in cold weather there is some heat present in the outdoor air.
“Auto” mode could cause your heat pump to heat on a cool summer night or cool on a sunny fall or winter afternoon. To avoid accidentally cooling during the fall and winter, use “Heat” mode. Likewise, to avoid accidentally heating on a cool summer night, use “Cool,” “Dry,” or “Fan,” but not “Auto.”
Heat pumps are designed to constantly run when winter hits and the weather outside gets cold. As temperatures drop below 30 degrees, your home's heat demand matches the production of the heat pump, requiring it to run continuously to move warm air through the home.
But why is 68 degrees the best winter thermostat setting? In winter, heat loss through walls, windows, and doors is a significant contributor to energy wastage. At 68 degrees, your heating system provides enough warmth to counteract this heat loss.
AUTO is significantly more energy efficient between the two modes since the fan is only running when your AC is going through its cooling cycle. This takes less power, which is more budget-friendly, with some estimates showing you can save as much as $50 per month just by keeping your AC on AUTO.
Optimal Heat Pump Settings for Summer
During the summer months, the ideal setting for your heat pump is around 78 degrees Fahrenheit (25.5 degrees Celsius) according to the US Department of Energy. This setting allows the heat pump to efficiently cool your home while reducing humidity and energy consumption.
Method #2: Turn on the heat and check the outside unit
Heat pumps use the outdoor unit to absorb heat from the outside air and transfer it into your home. Meaning that if you have a heat pump, you should hear the outdoor unit turn on after you switch the thermostat to HEAT.
Electrical issues such as a tripped circuit breaker, malfunctioning capacitor, or faulty wiring can prevent the heat pump fan from receiving the power it requires. Contact a qualified HVAC technician or licensed electrician for repair if a power supply issue is preventing your heat pump fan from turning.
The main reasons your AC unit outside is not turning on could be something that has tripped the circuit breaker, something is blocking the fan's airflow, or the condensing unit is damaged. Other potential issues could be the thermostat isn't set correctly or the compressor could be malfunctioning.