Heat Pump AC Condenser Fan Motor Not Turning
Heat pumps and air conditioning units use refrigeration to facilitate cooling and heating. The condenser is critical to that process and the most significant element of the condenser is the condenser fan motor. Air source units for both heat pumps and air conditioners have a condenser fan motor. With air conditioners it’s used to reject heat. For heat pumps, it both rejects heat and draws in air to the condenser coil, absorbing heat. If the fan motor fails, it will require repair for your unit to function properly.
In the beginning, you might discover a challenge with the system efficiency. You’ll find your unit isn’t heating or cooling properly. Once you’ve checked the obvious, the breakers and the units for any obvious damage, if you’ve determined the fan isn’t turning, shut the system down. If you have the expertise and the tools, it’s possible you can fix it yourself, but more likely you’ll need to hire a professional. Here are the things you need to look at to determine if a professional is the right call.
The first thing to look for
Your first concern is the type of motor installed in the condenser. Two basic types are typically used:
Condenser Fan Motor Inside the Condenser
– The most common is the PSC (Permanent Split Capacitor) motor. To begin checking the fan, use a long, thin screwdriver to reach in and try to manually start the fan. Sometimes that will get it going, but there’s more to do, outlined below.
– The 2nd most used fan motor is an ECM variable speed condenser fan motor. These require professional service as they are complicated and controlled by a circuit board. There will be a module attached to the motor casing. The problem could be with the module, circuit board, or even the motor.
If Flicking the Fan got it Started
If the screwdriver trick worked, there’s a bit more to do. Cut the power; there should be a disconnect adjacent to the condensing unit, but cut it at the breaker as well, just to be safe. Once the power’s off, look for any access plugs inside the grill for lubricating the motor. Some require lubrication, some don’t. It should be addressed during the annual maintenance check, but if you missed it, now may be the time. If there hasn’t been any permanent damage then that’s all that may be needed. Again, it’s highly recommended you let a professional perform this task, it’ll take him about 15 minutes.
Drip Plug for Condensation Removal
Examine the fan motor, looking for a blue plug next to the shaft. This is the drip plug. There should be another at the other end of the fan motor. Remove the plug on the bottom of the motor. Condensation moisture drips from the casing, and if it builds up it can develop rust and corrosion, causing motor failure. Some manufacturers even install a rain shield to further shelter the motor from rain.
The 2nd potential Issue – A Bad Dual-Run Capacitor
In this instance, you’ll notice the top of the capacitor is swelled up instead of flat.
Once again, it’s strongly recommended you hire a professional to address this problem. You’ll be dealing with high voltage and capacitors which can hold a charge even when the power is off. Proper handling to discharge them and prevent shock injury (or worse) is required.
Winter Worries for a Heat Pump
If you notice your fan motor isn’t turning in the winter, you may not have an issue. Periodically, a heat pump needs to defrost itself. When it does, the fan will stop moving as it aids in the defrosting process. Wait about 15 minutes and check it again. You’ll probably find the fan begins turning again, but if not, then you may need it checked. The same applies to “smoke” in the winter. It’s actually not smoke, but rather the clouds of condensation that occur in defrost mode.
If the Fan Motor goes Bad
It’s possible the motor has gone bad. If so, professional help should be acquired to replace the motor. There are alot of factors to consider as additional parts may need replacement. Professional expertise will ensure your safety as well as efficient repair. Special tools are needed and it must be wired properly for your unit to function correctly.
Finally, some units have built-in high-pressure switches that allow you to reset it should it be tripped in a high-head pressure event, shutting down the unit. However, this built in protection measure is typically a manual reset but continually resetting without addressing the underlying issue could damage the unit further. Consulting a professional is your best bet.
As you may recognize, while many of these repairs are things you could possibly do yourself, it’s always best to have a professional work to ensure your unit is functioning properly and will continue to do so.