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I installed a mitsubishi electric unit 4 years ago. Technicians have just gone back to check operation after customer complained it wasn't working. They are saying the compressor has failed due to water in the pipe work. Can this be case after 4 years of working and we nitro charge and then vac down to 500 microns on install?
if there was water then compressor will no longer work
Sounds like they are trying to pull a fast one. “Water in the pipe work” is quite an extreme fault; and while it’s true that excess water in the system would likely lead to a faulty compressor, there would have to be a leak in pipework laying in a body water. Did your pipe run through any places where water could lie (like a puddle on a flat roof etc?)
If they mean moisture or non-condensable, then this could also lead to a faulty compressor; however if the system was vacuumed to 500 Microns, then this is very unlikely to be your fault.
Are they trying to hold you responsible for the fault?
JV
Pipes do not run any where that they could get water in them and the was no leak. Yes they are trying to hold me responsible. Not sure what I can do.
4 years wow! That is so long past warranty
Ask to see maintenance records for the last 4 years and that much water would have given indication in other areas long before compressor breakdown. Take an oil sample and get it analysed to see water percentage and condition of system.
Would not run four years with water in the system, maybe with moisture but not free water. Plus how would it have got in?
How have they proved it had water in?
How can they prove it wasn't in there from the factory? Any factory moisture would have been isolated from your vacuuming then by the service valves....
If it's a customer with one unit walk away, if it's a bigger valuable customer suck it up or meet halfway
Hi Dan
Do these technicians work for you?
If not why didn't the customer call you back?
I would do as others have suggested oil test, check service history etc.
I would have thought that if it was water from new it wouldn't have lasted 4 years, must be a pretty good compressor.
Paul
IF there is moisture, it couldn't have been from original installation. Something else recently caused it.
Maybe a low side gas leak eventually pulled a vacuum, or someone with contaminated refrigerant had topped it up.
OR, there is no moisture and someone is trying to cover their tracks.:(
.
Do Mitsubishi Australia offer a five year guarantee?
If they do are they refusing to honour the guarantee because
there is water in the system?
As has been previously stated, water would not be in the system for 4 years
and the system still run, moisture could and would be in the system if it was
left in after install and it is possible to take 4 years to kill the comp.
You need to establish if it is moisture or water that they are claiming. Oil tests
and maybe even a refrigerant sample, but before you go to any expense you
need to see all copies of service and maintenance carried out since install.
If they can't provide that information, it either has never been touched or it
has been touched but by someone who does not follow correct procedure?
If it has been touched by another person other than you, how can they prove
was you who introduced the moisture, if it actually is moisture?
Rob
.
Hi.
What are they cooling?
Is it a comms room where it's. Thrashed within a inch of it's life running 24/7 all day every day?
This is the only time I have seen moisture in a suction pipe.
As the iced up vertical suction port allowed defrost water to work it's way down the threads.
And sat just a little way down the pipework.
It was routine service that sent us in the direction. That the unit was short of gas in the beginning.
I would ask for the documented amount of. Gas removed, to look into the pipework .
And as others have stated , the compressor to check the windings and the oil.
As you say, you pressure test and vac following. A good practice.
Good luck.
Get a second opinion on compressor failure, some one is taking to pi**.
After doing tests they are saying water was 2141ppm
Hi Dan
Most compressor manufacturers want systems below 40ppm, often virgin refrigerant comes with a higher ppm and they rely on the system filter drier to take the system to a lower ppm during the commissioning stage. I always charge systems with a drier in the charging line to remove as much moisture from the initial gas charge.
2141ppm of water is extremely high, and would cause depending on refrigerant type a fairly high concentration of hydroflouric acid in the system as the oil.gas,water and heat degrade the refrigerant in the system.
You don't say why the compressor failed , was it due to acid attacking the winding insulation causing a spot burn or full burn out, or was the compressor motion work heavily copper plated causing a seizure and a burn out, or was the compressor simply seized due to rust corrosion. No semi hermetic machine would last for 4 years with water of that magnitude , so someone somewhere is telling porkies. Try to get pictures of the compressor internals, as we say they evidence to every compressor failure is inside the machine
dan
over the past 4 years you have clue which muppets have been maintaining this plant there is no way on gods green earth that water has contaminated your system as it does not use water as a cooling fluid
this looks like a classic example of cowboys not dehydrating the system down to 1 torr or below and when charging not purging there lines introducing moistures wash your hands fella with this one
Although Mitsi might give three or more years warranty, not all contractors offer that to the customer. What is in writing. One year might be all the customer is due, even if there's an overlap for the contractor.
You need Mitsi to give a report on the compressor - they will tell you exactly why the thing broke. Get the customer to agree to pay for the report if you prove to be blameless, and then get the compressor checked out.
Ask the customer if any repairs/work has been done on the system since commissioning. Check it has been maintained properly.
I do not know how bad that statement of water amount in system is but it seems a lot and I am surprised the system would go for any length of time with that amount of non-condensibles in the system. It'd block up pretty fast I would have thought ...... couple weeks(?)
(Those engineers you sent to site seem to have shot you in the foot. They should have rung you up with what they found before shooting off their accusations. Maybe it changes nothing, but it is better when you tell the customer, not some arrogant 'I know best' engineer trying to look good.
There is one other point. It is all very well vaccing down to 500 microns when you install and well done for bringing a vac gauge with you (many do not and give the usual "It broke on last job"). But that's not the whole thing, is it. You should also check for a rise on the gauge (ie is there any moisture in the system?) 15-30mins and no rise..... you are safe. But not checking for a rise.... who knows for sure? You cannot look the customer is the eye and say "NO X-ing WAY MATE!" You just do not know for sure.
But in the wrong or correct, it will boil down to what is this worth to you. If a one-off customer that you think is trying it on, then, "Sorry mate, out of warranty". If there's a lot of work on the line, well, you might apologise for the problem and get him a new compressor etc etc. The latter has nothing to do with the innocent and the guilty -- it's simple sales strategy stuff.