Have you ever wondered why manufacturers shape condenser units like big boxes? If you look inside, you'll notice that most of the interior space is empty, aside from the relatively small compressor and associated wiring and hardware. However, the size and shape are critical to providing adequate surface area for the condenser coil fins and adequate airflow to remove heat from your refrigerant.
The large fan on top of the condenser is also no accident. This fan pulls air through the condenser coils surrounding the unit, helping to reject heat and cool the refrigerant before it travels back to your indoor evaporator unit. A faulty fan will substantially impact your system's ability to keep your home cool, so here are three things you should check if you notice your fan isn't spinning.
1. Is Your Compressor Turning On?
First, confirm that your compressor turns on. Have a helper turn a thermostat in your home a few degrees below the interior temperature. Setting a lower setpoint will cause the air conditioner to turn on, so you should hear the compressor firing up relatively quickly. Without the fan running, the compressor should be easily audible.
If your compressor doesn't start, the condenser may not have power. Check the outdoor disconnect and the air conditioning circuit breaker (or fuse). Some air conditioning units may also have an interior shutoff, although most don't. If none of these steps resolve the problem, there may be a wiring issue, and you'll need a professional for more help.
2. Does The Fan Start By Hand?
If you've confirmed the compressor is running, one quick and dirty diagnostic tip is to attempt to spin the fan blades using a stick or another solid object. Never reach your hand into the condenser since the blades can spin quickly and cause serious injury. Once you hear the compressor turn on, use your stick or another tool to attempt to spin the blades.
Watch your fan for a few seconds and make sure your "nudge" was enough to get it back up to speed. If the fan works properly and without any unusual noises, that's a reasonable indication that the capacitor may be faulty. While changing a capacitor isn't hard, it's a job best left to a contractor since it involves working with wires that carry line voltage.
3. Are There Unusual Noises?
If the fan makes unusual noises or you can see it trying and failing to start, your condenser fan motor may likely be dead. Condenser motors can fail for many reasons, including overheating due to debris, internal bearings wearing out with age, or even moisture damage. Note that you shouldn't use your system if the condenser fan isn't working, since the compressor can and will overheat.
The good news is that condenser fans are relatively inexpensive, so you don't need to start thinking about a whole new AC system if yours is faulty. Any trained HVAC professional can quickly and easily replace your condenser fan and get your system cooling your home again.
For more information, contact a company like Carolina Air Care.