Air conditioning compressor how to troubleshoot?

If your air conditioner won’t work at all, there’s a good chance that something is amiss with its compressor. This may sound like dire news, and it possibly is, but compressors can often be repaired. Before jumping to any conclusions, you should do a little troubleshooting to try and pinpoint the source of the problem. Keep in mind that there’s only so much that an everyday homeowner can do in this regard. Many of the tests that need to be done can only be handled by professionals.

What is an AC Compressor?

An air conditioner can’t work without a functioning compressor. On standard residential air conditioning systems, the compressor is typically located in the outdoor unit. As its name implies, the compressor’s main function is compression. In an air conditioner, it works by compressing cool, low-pressure, gaseous refrigerant until it is hotter and has achieved a much higher pressure. From there, the gaseous refrigerant is squeezed into the condenser. When refrigerant is still in the compressor, it is considered to be at the beginning of the air conditioning cycle. When an AC compressor won’t turn on, the process can’t begin.

Check for Power

The first and most obvious thing to do when your compressor won’t start is to make sure that the unit is receiving power. It is always possible that a fuse has been blown or that a breaker has been tripped. If such issues occur regularly, you should have an electrician take a look. It isn’t normal for the fuses and breakers to experience frequent problems. Constant stops and starts can wreak a lot of havoc on the compressor and on the air conditioning system as a whole.

If the fuses and breakers are fine, you may just have to call an HVAC contractor. The only exception is if you have access to a multimeter and know how to use it. If so, you can use it to check and see whether the right voltage is going into the compressor. Even if you’re able to determine that, you will almost certainly need to have an HVAC technician take it from there. The good news is that a problem like this can usually be resolved without a lot of time or money.

Troubleshooting Steps that are Used by the Professionals

It’s useful to know if an air conditioning problem originates with the compressor. It may not be great news, but it gives HVAC techs something to go on upon arriving. It’s easy to assume that you’re going to be out of luck and will have to buy a new unit, but that’s not necessarily the case. Compressors have many components, and any one of them can fail and cause a problem. The tech who arrives at your home will consider the following possibilities and attempt to rule out each one:

• Capacitors – In many cases, compressor problems are caused by faulty or broken capacitors. If the tech determines that the capacitor is to blame, he may swap it out for a hard-start capacitor, which may resolve the issue once and for all. The only way to troubleshoot a capacitor is by replacing it and testing the unit, so this is commonly done when an AC compressor won’t turn on.
• Start Relays – As with the capacitor, the HVAC technician may try replacing the start relay, which is the only surefire way to determine whether it’s working right or not. If the compressors works after a new start relay is installed, the problem will be resolved and you should be all set.
• Valves – A broken valve can create major problems in a compressor. The most common issue is that the refrigerant is liquid instead of gas when it gets to the compressor inlet. Under these circumstances, the compressor may still run, but the air conditioner won’t cool the air. Fortunately, replacing the broken valve or valves usually resolves the problem.
• Terminal Connections – The tech will also check the terminal connections to ensure that everything is tight and in place. A loose connection can cause some pretty significant problems. If your compressor works sporadically, it could be something as simple as this. There is also a chance that the terminal connections are just really dirty. A good cleaning may do the trick.

Dead Compressors

If the compressor in your air conditioner is deemed to be completely dead, you will probably have two options. You can either replace the compressor, or you can replace the entire air conditioner. The main determining factor is the cost to replace the compressor. If it’s less than 50 percent of the cost of buying a whole new unit, it’s probably the best way to go. If it costs more than that, though, buying a new air conditioner is probably the most practical choice.