can overfilling/overcharging damage a compressor?

[fredjchavez]

Need guidance from the experts out there...

Recently I had a 9000btu mini-split heat pump installed it was contracted out to various parites. Supposedly the compressor is a good unit and is screw/scroll. Here is a url that shows some of them:

http://www.airconditioner.com/MINI_SPLITS.asp

Anyway, it was installed w/o incident and worked like a charm for a few weeks. Extremely quiet and able to cool my bedroom down to mid 60's. 2 Weeks after installation, I happen to have noticed that below one of the flair connections was a spot of oil (confirmed by the slick fitting). I could not get the original installer due to scheduling so I contacted a major appliance repair (ie, major appliance retailor) and stated that the system was not cooling as well as it did previously. When the technician came, I showed them what I had found. After some measurements, he concluded that R22 had been lost and proceeded to charge which made sense. He measured the cold side temp, the indoor ambient temp, and the temperature of the discharge air to determine how much to charge. After about 2 or so pounds of R22 (seemed like a lot for a 9000 btu system), he concluded that the system was really low (not sure but the split systems do not hold much more than a wall unit). The unit ran/cooled fine and produced a steady hum which was as before.

Everything was fine for a couple of days. I started to notice a vibrating sound coming from the compressor unit..the sound came and went around 2 times per second. I could not find any loose screws or panel. I felt the lines and the vibration seemed internal. Things progressively got worse and the compressor would not start. It would try for about 3 seconds but all I heard was what seemed like a stalled or locked system trying to start every minute or so...this condition sounds like a stalled electric motor.

I called the same retailer and got a different technician. He proceded to empty the system and tried to get the compressor to start...He emptied over 1 pound of R22 (did not indicate exactly how much which I found curious because the previous tech knew to the ounce how much he put in). The system finally started but I noticed the same vibration from before but it was not as loud or noticeable. It was not a loud vibration but it appeared that something still was not right. The tech emptied more R22 but the sound did not go away altogether. I am mechanical engineer and not an hvac expert so I voiced my concern and questioned whether the overfilling had damaged the screw/compressor unit and the tech said everything was fine. The vibration stayed steady but two days later, the unit once again will not start and seems to exhibit the same locked condition. I have a few very basic questions....

Is it likely that the compressor was damaged by overfilling it? If the units can be damaged in this manner, how does the damage occur? Interestingly enough, this retailer does not mention anything about this possibility but I think there might be bias because this effectively would put the accountability squarly in their court...

Assuming there is damage due to overfilling, should the ratailer try to get the manufacture to cover via warantee or should they cover the cost since they over filled the unit which possibly damaged it? Honestly, I do not want them taking anything apart...I think it would be best to replace the entire outdoor unit (comments?).

The unit is under a 3 year warantee but my concern is that the retailor is going to say its a bad compressor and the manafacturer is going to say it was damaged by overfilling (if indeed this can be detected). There were several parties involved in the installation (mistake number 1 which is a big lesson for me) but logic tells me that this unit was damaged by overcharging since it NEVER NEVER made any vibration noises prior to charging it after the leak was found...

I have the first guy from the retailer coming out again (the guy that overcharged the system). Any thoughts or suggestions are welcome! At this point, I am trying to focus on whether unit is deffective or whether it was likely damaged by the major appliance retailor. I personally think that overfilling it damaged the compressor and the compressor is on its last legs (who knows if it will ever start at this point) but I am no expert. I cannot afford any down time as this is my bedroom unit and its hot enough to where I have to have a good air conditioner to sleep.

I have definately learned my lesson and will have a 1 stop shop that does the purchase, installation, testing, service, etc for future units but need your help and expertise on this one. Thanks!

[Andy]

Hi Fred
don't sweat the manufacturer will know why the compressor failed, they run compressors to destriction so that they are not caught out.

Sounds like the compressor pumped liquid refrigerant instead of vapour (gas).

You know who to blame, especially if you have a record of the added refrigerant. Normal practice dictates you decant all the existing charge and recharge to the plate charge or the plate charge plus an allowance per meter for extra pipe run after say something about 15 or 20m 9install manual will show all this)

Kind Regards Andy

[Brian_UK]

Damage is caused by pumping liquid.

Compressors are designed to pump vapour only, liquid caused hydraulic lock/shock and oil dilution. Oil dilution is due to the liquid refrigerant mixing with the oil in the compressor sump which then gets pumped out of the compressor and into the pipework.

The oil 'should' return to the compressor but it doesn't always do what it is supposed to.

As far as warranty goes I would imagine that you have lost the manufacturers warranty because you did not involve the original installer. The man who wrecked your machine is not going to admit his mistake if he can help it. You might end up with a Court action to recover costs.

The manufacturer when (if) he sees the liquid damaged compressor will deny all responsibility.

It's a bit like you having all of the oil taken out of your new car engine by a different service centre from the car seller, wrecking the engine and expecting the seller of the car to provide you with a new one - you know that's not going to happen.

[Lazarus]

I would have said there is a fair chance the unit had pulled a vacuum ..... air entered the system and is giving the results you see..... at no point do you mention the engineers actually evacuating the system before 'topping' up.
i would decant the system refrigerant, evacuate and recharge with fresh gas.

[brianubaldo]

hi fred

compressor can be damage by fluid coming from evaporator.

liquid is heavier than oil.(liquid will go down and oil will go up when mixed in compressor reservoir)
when the liquid refrigerant is suck by the compressor
the level of oil in the compressor reservoir will not be sufficient to lubricate mechanical parts because the oil will go to the system.

[IF THIS HAPPEN IN YOUR COMPRESSOR]
[YOU GOT A VERY BIG PROBLEM]

the warranty is void due to the technician repair your airconditioning is not authorized by the manufacturer.

if and only if you called a authorized service center of your airconditioning and this problem occurs the manufacturers will handle all the cost. no cost to be pay by you.
[and the technician will be terminated ]

[monkey spanners]

Are you sure it was on R22 and not R410A? We stopped using R22 in new systems here in the UK years ago as its illeagal in new systems.
Did the technician fix the leak before 'topping up' the charge?
From the symptoms you describe it sounds as if overcharging has damaged your compressor. When its replace make sure they blow through the pipework with nitrogen to remove any of the old compressors oil that may have been washed out of the sump or this could damage the replacement compressor.

Jon

[Brian_UK]

I would say this chaps, please check the dates.......

Also as you can see the original poster never came back with any response or updates.

[chris96]

Hi

As stated overfilling will cause major problems with the compressor, the main problem is the evaporator will be over filled with liquid refrigerant, the as the compressor runs this will draw up the suction line into the compressor.
Correct charging would be to weigh the gas in to the amount stated on the condenser name plate, altho, it sound like he charged by superheat which also is a good method but there can be mistakes made when charging that way if the conditions are not right.

All the best. Chris

[mamade salim]

hi,
i am salim the problem is when changing a damage compressor .the new compressor is giving a bad result .the evaporator is icing and the line pipe too. so i think its perhaps the new compressor is compressing the gas properly and make the air conditioner not working properly

[nike123]

hi,
i am salim the problem is when changing a damage compressor .the new compressor is giving a bad result .the evaporator is icing and the line pipe too. so i think its perhaps the new compressor is compressing the gas properly and make the air conditioner not working properly

First, I suggest you to start new thread with your problem, that way it will be seen by more peoples.
Second, you have changed compressor but cause of death of old compressor is remained unsolved.

We cant tell you nothing without measurements. Make these measurements and than come back. Than we will be able to help you.

Describe your AC and model# will be also helpful

Evap air in temp
Evap air out temp
Saturated suction temp (converted from pressure)
Suction line temp

Cond air in temp
Cond air out temp
Saturated condensing temp (converted from pressure)
Liquid line temp

Compressor model#, compressor current

[Suta Eugen]

Hello ,
I give you same advices about refrigerant charging :

1. for air conditioned =0,38 kg/kw;
2.for evap. temp. betwen 0..-15 =
1kg/ kw;
3.for evap. temp. below -15...-35=
2,7kg /kw.