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kingc66l
12-10-2010, 09:21 AM
Hi there,
I have just taken over a maintenance contact of a blast freezer 45HP condensing unit.
Is it normal to have a ball of ice built up on suction return on compressor?
Could there be evap fouling/superheat problems?
Cheers

ktm
12-10-2010, 09:33 AM
You sure it's not short of gas?

tradybrad
12-10-2010, 10:11 AM
to much liquid flooding back to comp?possible metering device issue?

mad fridgie
12-10-2010, 10:18 AM
Perfectly OK, just cool gas comimg back freezing the bell housing!
it is not at the crankcase!

desA
12-10-2010, 10:28 AM
What kind of suction line temp would you expect in this application?

roger head
12-10-2010, 10:30 AM
looks ok to me. Returning vapour could be as low as minus fifty so you are going to get some ice on the un lagged valve.

RANGER1
12-10-2010, 09:36 PM
A few tempretures would help like sump & discharge .

Foaming of oil as well .

You don't see this so much on ***** applications but ammonia its quite common to have a good ice build up with -10 C application .

lowcool
13-10-2010, 01:06 AM
id be more concerned about the anaconda and from what i can see lack of mounting leg on the head fan.good luck getting your gauges on in a hurry.
have a tendency to agree with others about return vapour temperatures,time to check your superheats.

Frostyguy
13-10-2010, 04:20 AM
You said its a blast freezer.
Typically, blast freezers are not on line 24/7 and are usually oversized in comparrison to a typical freezer. Make sure customer is using it as it was intended.
Quick Response:
> It can be normal: check your superheat at the compressor, at beginning of freeze cycles, and at the end. Customers sometimes try and use blast freezers as holding freezers as well. This can be a problem if the TXVs where over sized by design, or system wasnt designed for dual operation. For (Example: Your 45hp condensing unit was selected to meet the blast freezing conditions, however as a holding freezer only, it may only require a 5,10 or 15 ton system. Your TXVs in that senerio may not be able to throttle back. )

In either case, its always good to make sure you have an accumulator, oil seperator and in some cases a CPR or pressure limitting TXVs on any low temp units of that capacity.

powell
13-10-2010, 04:43 AM
As Frostyguy stated, as long as you have superheat you're ok. The ice formation simply means it's below dewpoint temperatures.

kingc66l
13-10-2010, 08:03 AM
cheers for the ideas guys, I go back to site next week to check this freezer havent had gauges on to check superheat yet.
The site was badly looked after before I took over this week, all other chillers and freezers had badly fouled evaps and condensers.