Flooded coil / surge drum.

[leeW]

Hi Guys.
I am looking for some advice on the "rule of thumb" best height to mount a surge drum on a flooded evap` . The unit came in lots of bits as a second hand plant and I am concerned that the mounting of this will be crucial to good performance. Any pointers ?
Thanks:)

[Magoo]

Leew.
What refrigerant is being applied?. Critical for design.
Best option is to go back to original supplier/manufacturer and ask all the obvious questions, they should be half friendly and open up with all info you need.
magoo

[US Iceman]

My first concern is to ask if the equipment was assembled as a gravity flooded evaporator and surge drum together (in original installation) or whether the pieces you have obtained came from various sources.

Before we worry about height of surge drum, we need to make sure you have the correct pieces...

[leeW]

Hi.
The unit is a very old frigo midget spiral running on a bank of 6 large Copland comps and as far as I am aware it was designed to be gravity fed. The drum is a vertical design with a Danfoss level control system AKS41 fitted. One of the other reasons I wanted to know about the critical hight is that I am restricted by head-height, and was wondering whether it would be possible to fit a pump? I realise that we are into all sorts of design issues here! We are running on 404A. The only original parts are the coil , slop pot (suction sep) and possibly the compressor banks as they are the same age.But not certain as evap is all galv steel and has oil drains so presume it could have been on Ammonia in some distant past.
The surge drum is 1900 high 550 wide mounted directly outside the room feeding through the wall into the evap the liquid line outlet fall is only 200mm from the bottom of the drum to the liquid inlet of the evap. The suction line height off the coil directly into the drum is at 1600. I just think that this layout could be causing problems should the drum be higher?
Thanks Guys.

[leeW]

I am told that the coil is rated at 100kw -aprox 36000 BTU , 30 ton and I need a pump cap of 150 ton? Using a ratio of 5-1. What would this equate to in pump size. Thanks Again.

[Rajkumar]

LeeW,

As you described the coils seems to be working on ammonia.

What are the SSt you required.

You can use horizontal surge drum.

You can check from Witt germany. if you required software please send persanal mail id.

raj.

[US Iceman]

WOW. This just keeps getting better from what I can tell. An old flooded ammonia evaporator being converted to R-404a.

At first blush, what you want to do sounds probable with spending some money. However, you also need to be concerned with oil recovery from the surge drum and then returning the oil equally to all of the compressors.

Secondly, the surge drum may not be large enough to accommodate the separation of liquid and vapor because of the use of R-404a. The surge drum was most likely sized for the operating conditions with ammonia being used.

Instead of trying to make this work yourself, why not insist on getting a guarantee from the supplier who sold this to you. He should supply all of the parts and piping diagrams. Install it exactly the way he says to and then if it does not work he has to fix it it.

What I'm afraid of is that you have a mixture of parts someone is trying to make work and I suspect this will lead to all sorts of issues that in the long run will prove more expensive to own and operate.

[leeW]

Thanks .
Unfortunatly we bought the unit (as a running plant on 404a) from auction,in Europe from a closed factory. It was very cheep for a spiral freezer and if we have to spend a little money on it then so be it. I would like to try a pump on it any advice on the choice / rate of flow from the pump.
Thanks again.