My air conditioner has been checked by AC technicians and after they got their service fees they told me nothing is wrong OR I can replace the whole system or a big part of it so solve the problems.

The first problem: Lets say the current home temperature is 79 and AC is set to 78. The AC starts blowing super cold air to cold the house but its too cold that makes us go and turn it off. Why AC does not do the job in a little slower speed instead of acting like a flash freeze machine. The AC repair company says nothing is wrong withe machine.

Second problem. The compressor in the condenser unit makes a blast sound whenever AC starts working, I removed the blades in condenser and ran the machine to make sure it is not fan motor or blades but I heard and saw the compressor making that big sound. Two different companies checked it. One says everything is OK and the other one says that compressor receive high voltage (or Ampere) and put something like a capacitor to regulate the current. It did not work btw.

So I really appreciate if you could share your thoughts. Bests Matt

closed as off-topic by ThreePhaseEel, Tester101 Jun 5 '17 at 11:53

This question appears to be off-topic. The users who voted to close gave this specific reason:

  • "Not enough information was provided to answer this question accurately. Please include the make and model of all devices and equipment, photos, diagrams, drawings, and any other information that might help people provide an accurate answer." – ThreePhaseEel, Tester101
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  • It would help if you stated what is your line voltage, what the power rating of each of the motors is, what brand of the AC system you have, etc. As to the too cold air, how cold, in degrees? You can buy an IR thermometer from the eBay pretty cheap and find out the actual temperature from the ducts. If your AC is over-charged, it may blow too cold. – ajeh Jun 2 '17 at 14:05
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    I've never heard someone complain about their A/C being too cold. Some plumbers seem to think you are complaining about your wallet being too fat. – Harper Jun 2 '17 at 14:46
  • An actual output air temperature would be useful. – isherwood Jun 2 '17 at 15:38
  • What Freon type? R22, R404, R134. How many ton is the system. And last the model would be helpful. – Ed Beal Jun 2 '17 at 17:31

I think you have a thermostat problem. Along with some unrealistic expectations of how heat and A/C work.

First it sounds like your real complaint is when the A/C runs, it makes the house too cold before it quits. That is a thermostat problem, and a thermostat is a $30 part. Specifically the working range (how cold to get it before shutting off) is wider than you want.

Keep in mind too narrow a range is bad. It means the unit is starting up very frequently, adding excess wear to the machine and being super annoying.

As far as A/C coming out "ice cold" as you perceive it, first you are not a thermometer. Don't believe me, play out in the snow and ice until your hands are very cold, then come in and stick your hands under a cold water tap. The water will feel boiling hot for a minute. That was a regular experience for me in my youth. As a human, your perceptions of temperature are just not reliable. Use a thermometer.

The A/C needs to come out cold, because it is a small amount of air that is going to "average out" with a large amount of warm air in the room.


So, what is the question you want answered. Most A/C units are either on or off unless you bought the ultra expensive units that only my" father-in-law" would buy. To try to answer your first problem; find a temperature that suits your needs, set it and forget it. The unit will cycle on/off as needed. Problem 2; compressors are on/off machines that do not have a slow start or ramp up speed. You get noises that seem loud so you should place the outdoor unit where the noise will impact you the least. And to my statement; if a service company puts a part on your unit, that you have to pay for, know what it is, ask if you really need it, and what function it will perform.

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    I have 40+ years of experience working on all kinds of heating and A/C. If you do not like the way the unit runs, decide what it is you want to accomplish and just do it. Don't cry about the way it runs, and yes the wiring and the concrete "slap" can be moved, It's only a slab of concrete and some wiring and 2 copper lines. – d.george Jun 2 '17 at 14:44
  • @MattS You need to chill out a little bit. If you want friendly advice, don't be indignant when you don't like an answer. No one here is being paid to do this. – longneck Jun 2 '17 at 15:07
  • @MattS While we are all strangers on the internet and skepticism is good, you were a little pushy about it and got owned LOL. I can confirm d.george's credentials. – Harper Jun 2 '17 at 15:11
  • There is another possible explanation for a noisy compressor. It could have become un-sprung from it's mount inside the metal enclosure we refer to as the compressor. If that happens (very rare) the compressor becomes very loud. The only fix is to replace the unit. – d.george Jun 2 '17 at 23:02
  • Back in the cave man days of about 1970, I saw a noisy A/C unit that someone added about 20+ lbs of R12 to , to correct a refrigerant charge, because he could not get the unit to cool properly. He should have replaced the TXV that was bad. ( the extra charge almost filled a 30# R12 bottle I carried ). I have no idea how he got that much refrigerant into the system. When the unit started it sounded like a gun firing, then got real quiet. Broke my high side gauge,also – d.george Jun 5 '17 at 10:35

As others have said, the cold air issue might just be a miss on setting your expectations. If you have a bathtub full of water that is too hot, do you put water in it that is "just the right temperature" or do you put cold water in it? Think of the air in your house as the water in the tub. Your AC unit puts a small amount of pretty cold air into a large amount of too warm air. This reduces the average temperature in the most efficient way by running the AC unit for as little time as necessary.

If the air itself is too cold on you, try placing an "AC Vent Deflector or Diverter" (amazon/google) where the air flows out so it does not get blown right on you where you sit. Also make sure it is not blowing directly towards the thermostat sensor, which will cause more frequent cycling.

If the problem is that the on/off cycles are too disruptive, your unit may have a tolerance setting that is too tight to the thermostat temperature. ideally, you want it to have a 3-5 degree range so it doesn't cycle on/off as soon as it hits and leaves the target temperature. Also possibly check on your thermostat itself to make sure it is functioning properly.


With a conventional HVAC system the compressor jumps to life with a bit of jerking as it comes to speed and when stopping. If the starting capacitors are bad it will not have the motor torque to start and usually blow fuses.

There are new systems that use VFDs (variable frequency drives) to control the compressor ramp and speed but these create new problems with oil recovery because of the lower speed. With an existing system you are stuck with the thump on startup and shutdown. This is normal.

As far as too cold it may be possible to add speed controls to your blower but this would risk freezing the evaporator coil. HVAC systems are designed for peak load (unless a very new high end system) The compressor runs at full speed cooling until the set point is achieved then the compressor shuts down. To me it sounds like your system may be over sized so it can maintain the set point on the hottest days.

This last part of my answer is more opinion based on experience since your question appears to be questioning 2 different HVAC techs with a properly working system.

There are trade-offs on system design and how much $$$ folks are willing to spend. I would go for a slightly over sized unit without all the bells and whistles because the system life. Repair parts for a variable speed system are many times more expensive and they do fail more often. Once a system is installed you are stuck with it until it needs replacing trying retrofits and other gimmicks usually is just a waste of money especially if converting from a mineral oil lubed system to a synthetic lube. It may work for a while but usually a catastrophic failure costs more in the long run.

Although I am an electrician I do hold universal HVAC & MVAC licenses and have installed and maintained quite a few systems ranging from a few ounces to hundreds of pounds Freon charge.

  • @ isherwood @Ed Beal Thanks. Wonderful remarks. However, as regards with the compressor sound, it was very quiet at the beginning when I moved to my current house, but then starts its explosion sound that if you are in street you would not appreciate the nasty loud noise. And it is next to my child's bedroom and made so much trouble for us. I am still looking forward for answer here is my photos and videos of the compressor and other stuff in condenser unit link – Matt S Jun 2 '17 at 16:22
  • Have you checked the rubber isolation mounts. One may have come loose or cracked allowing metal to metal contact. It only takes 1 bad one to make a heck of a racket, if this is the case it will get worse quickly and can damage the line set & power to the compressor. – Ed Beal Jun 2 '17 at 17:30
  • Please see this pics and video I shared link Its a 5 ton Leanox and made in around 2005. Must be R22 then. – Matt S Jun 2 '17 at 18:45
  • I did not see the "link" earlier, both the 80 & 10 uf caps look good not sure what the 5 was, your system is R22 13 lbs and ? Oz. I could hear some compressor noise but it did not sound that bad to me. I don't like opening R22 systems because of the cost I would put gauge only (no lines) on the high and low pressure ports only and verify the suction and discharge pressure. If there is a leak and the system is low on Freon it can cause high head pressures. Unfortunately r22 is being phased out and is getting horribly expensive with proper pressures it may be just worn out or getting there. – Ed Beal Jun 2 '17 at 19:06

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