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Signs That Your AC Compressor Is Starting to Go

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If you have had your central air conditioning system for some time, then it may not be surprising to learn that the unit requires some major repairs. These repairs may include the replacement of a burned out compressor motor. Compressor motors rarely burn out completely at one time unless the unit has a considerable coolant leak and the motor overheats. This means that you should notice some pretty obvious signs that the compressor is starting to go. Keep reading to learn about a few of these signs.

Hard To Start

If you frequently shut your air conditioner off while it is running or if the electricity goes out in your home often, then the AC unit may have some difficulty starting up. This is called a hard start and you may hear the unit humming or buzzing or the unit may vibrate as it tries to work. There are a few other things you may notice that indicate a hard start issue. If the unit stutters, starts to cycle on, and then the breaker trips, then this is an indication that the compressor is working hard to pump coolant and creating a great deal of heat in the process.

In some cases, the compressor may be able to start up, but it may only run for a few minutes. In this case, a safety shutoff attached to the compressor is likely turning off the unit before the breaker can trip. If the compressor is still in relatively good condition, it may run after a few attempts to start. 

If the AC unit has been running for several hours and has been turned off, then the compressor will retain a high pressure environment inside the compressor head. The pressure will reduce as the unit sits, and the unit may not turn on until the happens. If you notice this, then the compressor likely cannot handle starting any longer under variable pressure conditions and this is a sign of long term wear. 

If you notice that a hard start problem almost completely stops your air conditioner from working like it should, then you are probably in need of a new compressor. However, if the motor seems to work after a bit of effort, then you can ask an HVAC professional to install a hard start kit inside the unit. A hard start kit is a capacitor that provides the compressor motor with a boost of electrical energy to get the motor moving. While this will not restore a worn compressor, it can prolong the need for a replacement. This is ideal for some homeowners, especially since AC compressor replacements are among the most expensive fixes and can cost you as much as $1,600. 

Low Or No Cool Air

If your AC unit is producing warm air or a low volume of cool air, then the issue may be related to a poorly working compressor. If low air flow is the issue, then the piston, scroll, cylinder, or blade that actively compresses the coolant may be partially frozen. This means that the unit is not placing the refrigerant under enough pressure and the under-pressurized coolant is not absorbing as much heat as it should. The result is warm air moving through your ductwork and vents.

A low volume of cool air can also be caused by the deterioration of the seals and valves inside the compressor. This sort of deterioration can cause the coolant to leak out of the compression chamber. Smaller volumes of coolant will then move through the system. Sometimes leaks may cause the coolant to be forced out of the compressor altogether. The entire AC system will experience a low volume of coolant and your HVAC professional can check for this.

In some cases, the compressor can be rebuilt, especially if deteriorated internal components can be identified. This can reduce your repair costs, but your AC unit may be out of commission for some time while the repairs are made. Make sure to consult with an HVAC professional like Apollo Heating & Air Conditioning about your options so you can decide on the best repair plan.