opinion about compressors

[Servicefrigo]

What brand of compressors is the moust usual.You can count on.

[chemi-cool]

I would say, all of them but on the semi hermetic side, Copeland and Bitzer come out more while in Italy you might see more of Dorin. Carrier and Trane are most likely to be found on OEM.
Hermetics are, Tecumseh (also the french), Maneorup, Danfoss, Embraco and all of its companies, copeland.

They are all good.

Why do you ask?

Chemi

[Servicefrigo]

You put Copeland,before BITZER ,deliberate.TECUMSEH before
EMBRACO also.Forr us important is the price,but don*t forghet the quality.

[chemi-cool]

I did not make any order, its just the names.
I believe that they are all fine compressors.

Chemi

[Danfoss]

In my oppinion, the best semi-hermetic compressors are Bitzer, and the best hermetic compressors are Copeland Scroll

[Thom101]

i agree about that the copeland scrolls are good compressors, nut ive never had any problems with any recips either. manufacturers like maneurope offer a preety good range and they last forever.
on semi's i fit loads of Carrier semi's for marine use, providing the fridge circuit is installed correctly (purged while brazing etc.) then we dont get many problems.
i would stay clear of screws though! we installed 3 big chillers on top of a building and 2 months after the chillers were out of warrenty 3 compressors went down, each cost over £15.000 to replace. needless to say the client was not happy!

[frank]

manufacturers like maneurope offer a preety good range and they last forever.

Manu's are also very forgiving on liquid carryover

[wesmax]

Here we use mostly tec and copeland but maneurop is very good but cost more and Bitzer is realy catching on.
wesmax

[Servicefrigo]

can eneybody tell me something about M.Q. Compressors

Regards

[peterweston]

If this is a compressor replacement? Probably more important is why it had failed? Taking the right precausion for the new compressor is very important. Contactor/ start gear replacement, liquid line/ burnout drier, check the superheat (most compressors require a strick "k" return temp. I see may compressors not surving long anymore, a year at the most. How many of you purge nitro when installing a new comp? I know i have missed that simple step sometimes. But back to the point of this forum, many compressors suit may situation, i see mostly tecumsies fail the most, but this could be beacause there are a lot more of these out there. Condensers sizing and subcooling of the liquid are the keys to compressor performence. Warrenty on a compressor needs to be also taken into consideration.... and the list goes on.

[chemi-cool]

Hi Servicefrigo,

I think that MQ compressore, are for compressed air.

Chemi

[Servicefrigo]

No Chemi
Somebody request 1 pcs 140 kw M.Quay.compressor. This guy work with chileers he is a instalerr. I don't have any technical data about that.

[Peter_1]

i agree about that the copeland scrolls are good compressors,

what about the Bencmark compressors (Bristol)?

[chemi-cool]

MacQway dont make compressors.
You need the chiller model and then you can find the compressor you`re looking for.

Peter, Bristol compressors are part of York

Chemi

[750 Valve]

Can't beat the green machine , Bitzers are the go for semi's. I know of a 4H installed on the main dishwasher in Sydney convention centre ( manufacturer Hobart Germany) running 65'C condensing on R134A for preheating rinse water, it gets an annual maintenance (which doesn't include oil change) but I don't think I can remember it ever having any compressor problems, a few gas leaks though. Been there around 8 to 10 years now.
And the award for Consistantly Noisiest Recip goes to..... (drum roll)
Copeland.

[Peter_1]

We always use Bitzers: good machines, very quit, well priced,...Real german craftmanwork.
Same for their screws (only used them twice)

A compressor for a dish washer? Sounded strange when I first read it. From where do they get the waste heat?

We used in the past Bitzer compressor on R114 for oak wood dryers. The condensor was mounted just behind the evaporator and the temperature in the oven where the machine stood was around 60 °C or some 140°F.

But they won't give me their color - Bitzer green - so that we can paint our racks in the same color.

[chemi-cool]

Peter,

In every good paint shope or building stuff or DIY they have a paint mixing machine.
Bring them a part of Bitzer (new) and I'm sure they can mix you the right colour.

Chemi

[Peter_1]

There was still a difference in color but that's in fact not so important.
Pack is almost ready. We think to deliver it Wednesday.

[750 Valve]

Peter, I use "Rivergum", available in Oz in a spraypack by most major paint manufacturers, its so close its not funny, only in bright sunlight can you really notice, most of our gear's in plant rooms so we get away with it.
The Dishwashers are available from a company called Hobart, I believe they're based in germany, just tried a quick look on the web but could only get the oz branch which doesn't have the machine on their site.
Basically the comp discharges to a tube in tube condenser, when goods are being washed and conveyer belt is moving hot water is passed through this coil and sprayed on the goods to rinse them at the end of the conveyer, system is designed to deliver 65'C + water to rinse for sanitary reasons.
In addition 3 solid plate stainless steel heat exchangers are piped in series after the tube in tube condenser underneath the macine's conveyer belt in 3 separate tanks. The machine runs until these tanks reach 65'C and then runs to maintain this temperature, regardless if conveyer is running or not (that means no water flow through first condenser, only system condensing is the 3 tanks trying to achieve 65'C!!!). Then a standard horiz. receiver, liquid line feeds to a DX air cooled evap coil, the cool, dry air is used ducted to either end of the machines conveyer belt (entry and exit) and used to dissipate steam produced from the machine.
VERY strange to get your head around first time, 65'C + condensing temps... I no longer work for the company with the contract on site but still talk to the guys, she's still going strong. Heat reclaim in a big way! I suppose it beats running electric elements to heat, although I don't know if I'd buy one, my 2 drawer domestic number does me well, and NO, I'm not thinking of converting it.

[Servicefrigo]

1;About MQ compressors yes is true MQ does*t made compressors for Refrigeration apliances you have right.
2;All Compressors are good as long they are new,
3; I have another question to put in discusion now. The answer is very important for me or whoever who don*t now.
We have a multicompressor units whit 3 screw frascold for a negative temperature - 25*C & another multicompressor units with 4 screw frascold for a pozitive temperature + 2*C.
both units have the suction line line with snow upon & allmost half of each compressor is full with ice.
Is this a normal situation?

[Peter_1]

For the negative pack, I should say, this will be OK as long superheat is +/- 15 to 20 K measured at the compressor body but there is definitely something wrong with the positive pack.



One of the TEV's on this pack is working not properly: oversized duse, bulb not attached, fans not running, too less load on the evaporator (filters clogged, ice build-up, fans not running..)
You have to check each evaporator.

Don't let it run long time this way. The oil will wash out the sump.

Re-readed my post: I suppose the +2°C is evaporating temperature or are you talking of room temperatures? If not, then you're compressors evaporates at -10°C or so and frost is then a litlle bit more acceptable but you still have to check because your SH is very small, in fact... too small.

And as far as I know, McQuay is making huge compressors: centrifugals, pistons...

[wesmax]

Well as a general rule an ofc (oil failure control ) is to do just that. It will protect against flooding , or sonetimes could be a very diluted oil with the liquid , as far as low oil goes it will protect but it has a delay so it could be with out oilfor as long as the timedelay several times and this could do damage to mains and rod bearings. As far as your low temp unit I do not understand the lingo here so no comment.
Wes

[Servicefrigo]

This compressors are mouted 2 years ago .the company ho made instalation is a hungaryan company,could I say with smart & profesional technicians .Thill now the owner have*t problems except the usuale maintanance.
The temperature -25*C respective +2 *C are the rooms temperature. the evaporating temperature is below. The owner of this units have employe a friend of mine ,probably is cheaper for hym (even this one does*t now the right answer ) but if the owner is content nowbody will change the situation .The question remaine
Is not dangerouse to ghetn off liquid in a wrong place ?
Peter what means SH?

Regards

[wesmax]

Hi well after reading over your notes I do have some trouble understanding what the problem is but lets start at the start.
What is the coil blower or bear pipe , what refrigerant , do you have surge drums or accumulator in the suction line , what type of expansion device do you have TXV ,float ,hand x , do you have an idea what the suction temp is at the compressor.
I will answer you back tomorrow it is late and time to go to bed.
Wes

[Peter_1]

Sorry Servicefrigo, SH is Superheat.

If these phenomenas didn't happened in the past, then you have to look to a bulb of a TEV which has loosen fram his copperline, a frosted evaporator ,clogged filters, a heating wire which is influencing the bulb of the TEV,....

[Servicefrigo]

wesmax there is eny problem at all ,the question I put- it here is just a question, it does*t concern me because I*m not involve in .Just for my curiosity.Ofcourse the multicompresor units have a big acumulator on suction line maybe is not enough bigger.? From the beginning the back side of each compressor whose full of ice.The refrigerant they use is R404a.
Regards

[Servicefrigo]

Hi
A bad or a good news .The discharge line from first multicompressor units,( negative temp.),was blowing up .400 kg R404a & 90 kg oil BSE 170 was release in athmosphere ,instantly After 2 year from mounting .The Hungarian company recognize they-r fault and change for free the all pipe,R 404A ,& oil also.
Now the suction line have not a piece of ice or snow on it . The instalation goes normaly,even better i could say
(maybe because is winter)

[Servicefrigo]

Have someone of you, a equivalent list for compressor
Thank you

[Peter_1]

They recognised which fault?
What was the cause?
What have they done to prevent happening this again?

Important questions to ask right now.

[Servicefrigo]

On a pipe from the liquid line the weld wasn*t professional made & it seem the thickness of all pipe wasn*t right proper also.The conection betwen pipes wasn*t made in the flow direction .So they was put in situation to change the all line.Probably the HP
was grow,from a reason.