foster compact freezer room

[Andy AC]

Hi guys, i hope you can help

I fiited a new compressor to this freezer room (straddle/monobloc) about a month ago and it has beeen a problem ever since - never gets down to temp, spends a lot of its time on defrost (electic). It has an eliwell control unit fitted, don't think it is original.
Could some body tell me what the parameter settings concernig defrost settings should be. From memory it was an eliwell EWPC 974.
Would this control defrost on demand or just stick to its timed intervals, or both ?
Unfortunately, I never diagnosed the compressor, someone else did and ordered a new one for me to fit, I never checked it myself, big mistake, when I fired up the new one, the condenser fan was seized - oops, old comp prob just out on overload, but my colleague was convinced it had gone
The new one came with a rotaloc valve insted of a stub, which meant a small suction line modification, but apart from that and a proper drier being fitted, pipe layout pretty much the same so I put just a smidge more gas than the factory charge.
So far the best it has ever (alledgedly) done is -16 C but wont hold.
Any help apreciated

Andy

[Brian_UK]

Eliwell control handbook here:-

http://www.thermofrostcryo.co.uk/tec...ndbookv2.0.pdf

[Andy W]

An Elliwell control will display def after a defrost has been terminated and until it reaches the temperature set point, you can alter a parameter of the controller so it locks on to the pre defrost temperature.

I work on mant Foster mono blocks and the problems are usually blocked condensers, faulty contactors, vaporiser pipes rotting (easy to reach on a monobloc) contactors for the compressor and cond fans, small pencil switch for the second condenser fan and dont forget the hot gas defrost valve if one is fitted, once these start to leak past the evap temp is obviouslly raised.

Also check the old compressor against the new make sure it will achieve your required evaporating temperature, is the door frequently opened, this will make pull back time longer like at McDonalds where they are in the rooms constantly in this case call to site first thing next morning to check room temperature before any one goes in.

[leftjobrunning]

An Elliwell control will display def after a defrost has been terminated and until it reaches the temperature set point, you can alter a parameter of the controller so it locks on to the pre defrost temperature.

I work on mant Foster mono blocks and the problems are usually blocked condensers, faulty contactors, vaporiser pipes rotting (easy to reach on a monobloc) contactors for the compressor and cond fans, small pencil switch for the second condenser fan and dont forget the hot gas defrost valve if one is fitted, once these start to leak past the evap temp is obviouslly raised.

Also check the old compressor against the new make sure it will achieve your required evaporating temperature, is the door frequently opened, this will make pull back time longer like at McDonalds where they are in the rooms constantly in this case call to site first thing next morning to check room temperature before any one goes in.

I had a similar problem with a monobloc recently, went through all defrost parameters, everything, wouldn't go below -16, was about to throw myself over a bridge when I cleaned the condenser out of sheer boredom (it looked clear).

Thing shot down to -20 within minutes. I nearly vomited.

Prob not the same problem but you never know. Sometimes it's the dumbest thing you miss.

[Abe]

Eliwell control handbook here:-

http://www.thermofrostcryo.co.uk/tec...ndbookv2.0.pdf

Brilliant link Brian.........Thank you
Printed whole document for easy reference

[Brian_UK]

Brilliant link Brian.........Thank you
Printed whole document for easy reference

It's the wonder of the web isn't it Abe.

There is just "so much" information out there now you question how we ever survived before

[Abe]

How did we "ever live without it" is a very pertinent statement..

I remember in the not too back distance..........I could sit back,and really enjoy a tv program.

Now, its just a coulourful flashy blur.....

In those days, when you wanted some info......it was a trip to the library, or if you were lucky you had the full set of Brittanica on your shelf.

Now, at a touch of button........every one is a fountain of knowledge.....

These days the days pass, like hours passed in them days......

I cannot decide if its better now........