AC Compressor Repair
The ac compressor is the main motor in the condensing unit. This will be the large black device that’s in the bottom of the outside condensing unit. This is motor encased inside a welded shell with one of several different types of compressing pumps. If you read the page on fans motors, you understand a little bit about the controls that protect this compressor. In my opinion the compressor could not have too much protection.
There are several controls that I like to see on a compressor. A low pressure freon switch, a high pressure freon switch, and internal electric overload, and an internal high-pressure relief valve. This seems like a lot of controls, but without these controls compressors don’t have a very long life. Manufactures have got to the point where you only see high pressure and low pressure switches on the higher priced units. Just a tiny bit about each control.
A low pressure freon switch turns the unit off when the unit gets too low on freon to operate properly. The high pressure switch turns the unit off generally when you have a fan motor failure. Internal electric overload protector stop the flow of electric on heat or high amperage, it will normally reset itself. The two internal controls, being the high pressure relief valve and the internal overload protector can not be repaired. These two controls are installed by the factory inside a welded container that houses the motor and compressor pump. This complete assembly is what is called the compressor. The high pressure and low pressure freon switches can be field replaced.
When a compressor fails it’s important to know what caused it to fail. If the technician cannot determine what caused the compressor to fail. There is a pretty good chance a replacement compressor would also fail. So when you’re getting prices to change a compressor, what you need to understand is that enough time needs to be spent with the unit after its running again, to be able to find the problem that caused the compressor to fail in the 1st place.
This is something that we have to investigate, with years of experience to assist us in finding out the cause of the failure. Not finding the cause generally gives you the opportunity to change a compressor again. It might be two weeks, might be next summer. But if you did not isolate the problem and correct it, you will get the opportunity to do it over. There are so many things that can cause a compressor failure that it would be hard to even mention them all. If you’re having a problem like this, feel free to call me I don’t mind talking about the problem and the solutions to it.
Over the last couple years the cost to replace the compressor has doubled. The wholesale cost of a compressor is gone up so dramatically that it now becomes a accounting decision. Do I replace the compressor or do I replace the unit. A compressor will only come with a one-year warranty on the part. Whereas most units will come with at least a five-year to ten year warranty from most of the manufactures.
The cost difference is generally about 75% for compressor replacement, of the cost of a new unit. So for a few hundred dollars more, you divide that out over the warranty period of the new unit and your money ahead. You should strongly look at this any time you have a compressor to replace. A new system should always be considered.
My company has one of the lowest compressor failure rates of any company in town. We take a personal interest whenever a compressor is lost. We try to inform the customer of all the problems that can arise when changing out a compressor. Again I want to stress that if you do not find the problem that caused the compressor failure, it will generally cause the next one to fail also.
There are a lot of additional things that should be done on the compressor change out. Sometimes it’s difficult to try to convince the customer of all the necessary safety steps you should take to ensure that you don’t lose another compressor. If I were changing a compressor at my own house, I would install every safety device that I could to try to make this compressor last. Such things would be a liquid line dryer a suction line dryer and a new run capacitor, new start capacitor, and possibly acid neutralizer if needed. The systems initiating contactor is something I would also replace.