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Tips to Turn on HVAC Compressor

Having problems switching on your HVAC compressor? We are here to help


After a long day out in a hot sweltering sun, all we wish to do is go back home and have a good night sleep in an air-conditioned room. But imagine your AC not working on such a day. Now that would be a problem.


Well, in that case, we have got you covered. The first step will obviously be to identify the problem. Most of the times the problem is with the HVAC compressor. So what exactly is HVAC compressor?


(Remember there is so little that we can do about AC on our own. It’s the job of the technician and it would be better to consult one in case you are unable to solve the concern)



The air conditioner is based on two laws of nature. First is the fact that heat flows from the high-temperature region to low temperature region. Second is that gases flow from the high-pressure area to low pressure region.



The compressor is the heart of the AC. As the word suggests, the compressor compresses the refrigerant gas that is decreasing its volume and increases its temperature and pressure. It may seem funny to raise the temperature of already heated gas, but it is essential that the refrigerant fluid must be at a higher temperature than the surrounding environment.


This is because of the fundamental law of physics mentioned in the above paragraph that heat flows from the high-temperature area to lower temperature area. Your compressor should be well maintained to efficiently transfer the heat your refrigerant fluid is carrying to the surrounding.



If your HVAC compressor is not starting the first and the foremost thing to do is-



Check electrical connections

Take a look if any of the wirings is damaged or if the fuse is blown. Carefully check all the links, also the one which connects your HVAC compressor to an outlet. If you find any problem, then you know what to do. Just call an electrician and get your HVAC compressor fixed.



Maintenance and Cleaning

Shut down your system entirely by pulling out the disconnect block out of the electrical box. Make sure that the power is off using voltage sniffer.


Once that’s done start cleaning up the dirt and dust from the filters and condensers. The accumulation of dirt can cause blockage and reduce the airflow, which can be the reason behind your AC not switching on. Even if this is not the problem behind your current situation keeping this part clean will help keep your HVAC compressor healthy. So add it in your regular maintenance routine.


A clogged condenser coil will overheat the compressor resulting in your HVAC compressor getting damaged. If your luck is proper simple repairing can bring it back to working conditions else you’ll have to replace the compressor altogether.


If your AC doesn’t start even after this, it may be possible that a part or two of your HVAC compressor have stopped working.


Replace Smaller Parts

Your HVAC compressor is made up of various small parts. Damage in any of those can cause your compressor to stop working. In this case, you can call up a technician, get that part replaced, and you’re good to go. They are pocket-friendly as well.


If your HVAC compressor still won't start, it is high time you call a professional. The HVAC technician will check out the following parts and determine the reason behind your situation.

  • Start relay
  • Terminal connections
  • Capacitors
  • Valves


If you’ve got an exact quantity of electrical skills, you’ll want to change capacitors and starter relay before you usher in outside facilities.

If a capacitance or starter relay replacement still doesn't fix your issue, it's positively time to usher in an expert HVAC technician. A lot of advanced repairs might involve dangerous chemical leaks and different safety hazards that are best handled by trained professionals.


Relays and capacitors

Ask any technician, and that they can tell you that concerning 85 % of HVAC repairs involve electrical systems. Relays and capacitors are the things that are needed to be examined first. They are responsible for providing power to your HVAC compressor. This is the cheapest method to get your AC stated again. If it’s been more than five years to your AC, then you should consider replacing the whole unit to cancel out any future issues.


Your Capacitor acts as a short term power supply which runs the blower motor, compressor and the outside fan. In case hear a humming noise from the unit turn it off immediately. This may due to the compressor trying to access the non-functioning capacitor. If not paid attention this may result in severe damage of not only the capacitor but the whole motor. Replacement of compressor should only be done by a trained HVAC technician. This will cost a little more, but safety stands first.


If replacing parts does not solve your problem, you can either return your HVAC compressor or the entire Air Conditioning (AC) System altogether. You can make your decision based on the cost required to get your work done. If the value needed to change only the compressor is much lesser than the entire unit, you should go for it. But if the margin is not much, you should think about replacing the whole thing.



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