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Peter_1
16-04-2004, 02:50 PM
Excisting condensor.

What about installing a second one (increasing capacity) but not of the same size as the original one?
First case a bigger one and in a second case a smaller one?

What should be done/installed/foreseen so that both are 'fed' with correct capacity? So that the discharge gasses don't follow the way of least resistance.
Purpose is try to condens as low as possible.
Is it anyway possible?

Any comment is welcome

Mark
16-04-2004, 08:42 PM
Hi peter :)

Yes ive seen this done two condensers side by side one smaller than the other.
I believe as long as the pipe work is teed off equally the losses to one condenser would be negligible.

Mark :)

Mark
16-04-2004, 09:14 PM
Remembering that the evaparator and condenser must have equal capacities ;)

rbartlett
16-04-2004, 09:41 PM
Remembering that the evaparator and condenser must have equal capacities ;)


why? what happens to 'heat of compression' ?


cheers

richard

Mark
16-04-2004, 10:25 PM
LOL just read my post :o

It would be true if refering to a condensing unit ;)

Peter_1
17-04-2004, 06:29 AM
It's on a pack. Client had problems last summer with too less condensor capacity and needed to spray water on them.

Engineering office said that if you don't install exact the same condensor, it will never work. Because actual condensor is an older type, there must be installed two new ones or a big one.

I disagreed with him because we sometimes uses recup condensors which we had to take over when installing new ones. And in many cases , they're from different brands and size. It worked but I never measured temperatures or pressures over the condensors.

Latte
17-04-2004, 11:57 AM
Hi Peter,
You want to come and work over here. Last summer all the major supermarkets were spraying water on condensers to stop them tripping out in this area. Tescos,Sainsburys,Morrisons,Somererfield are the ones i know about. It's all down to cost as per usual. One year these people might realise that ambients can hit 30 degree's in the UK. Until then we will just have to keep buying garden hoses & sprinklers from the DIY stores

Regards

Raymond

Latte
17-04-2004, 12:00 PM
Hi Guys, just had a thought (Dont knock it)

All Major retailers put their condensers on the roof so in summer the sun beats down on them all day. Has anyone ever tried to build a canopy over the top the stop the sun going directly onto them or would it just prevent the heat escaping & therefore not work.

Regards

Raymond

Andy
17-04-2004, 04:56 PM
Hi
if you are using a vee block type condenser you can fit a minimiser type system, in essence a set of sprinker heads with a mesh curtain to reduce drift, much easier that a new condenser.
A smaller condenser fitted with a large one, no problem provided you trap the condenser outlets to craete a liquid column, or possibly pipe both both outlets into a low velocity header witha slope away from the condensers and a liquid opt on the end to ensure gas doesn't enter the liquid line.
Mark equal tee's don't work properly on any conderser configuation :( , you might be able to get this to work if you cycled fans on a mirror image sequence, but even that is touch and go :p
trap the outlets and create a liquid column, much easier. :)
poor condenser pipe work is a common thing on supermarket installations, nice big well sized condensers, mostly piped incorrectly. :mad:
and the multiples wonder why they had bother last year :o

Kind Regards. Andy. :)

Mark
17-04-2004, 05:36 PM
Andy the things you point out i felt didnt need explaining to peter as i guessed he would probably know these points ;) .

Andy
17-04-2004, 05:48 PM
Hi Mark :)
well that's me put in my place :D :D
Kind Regards. Andy :)

rbartlett
17-04-2004, 05:48 PM
Hi Guys, just had a thought (Dont knock it)

All Major retailers put their condensers on the roof so in summer the sun beats down on them all day. Has anyone ever tried to build a canopy over the top the stop the sun going directly onto them or would it just prevent the heat escaping & therefore not work.

Regards

Raymond


we quoted some work in saudi -so we shipped the units and a load of wood to make such a shelter

when we got there we noted that no other bugger bothered so when we flew out again there was a pile of wood left on site...

cheers


richard

Latte
17-04-2004, 07:55 PM
[QUOTE=Andy]Hi
if you are using a vee block type condenser you can fit a minimiser type system, in essence a set of sprinker heads with a mesh curtain to reduce drift, much easier that a new condenser.

Hi Andy,
For us Uneducated ones whats a vee block type condenser & do you know of a website or have any info on the sprinkler system.

Regards

Raymond

Andy
17-04-2004, 08:02 PM
:) Raymond
vee block is just two coil blocks mounted in the shape of a vee with the fans on top, used a lot in packaged water chiller.
As for the minimisers, I don't know of a web site, but I will ask the guy who fitted them on various sites i've been on to tell us where he got them.
Kind Regards.Andy

frank
19-04-2004, 12:19 AM
Have a look at this site http://www.epsltd.co.uk/EcoMESHcatalogue.pdf on page 4 there is a picture of a V block condenser at bottom left

RogGoetsch
19-04-2004, 01:00 AM
Studied this many years ago and only remember that the problem is in pressure differential which can back refrigerant up into one condenser.

Solution was to calculate proper line size (larger than expected) between both condensers and the receiver, which would allow pressure equalization between components.

Suspect the Prof could provide a more sophisticated answer.

Rog

Mark C
22-04-2004, 01:36 PM
Studied this many years ago and only remember that the problem is in pressure differential which can back refrigerant up into one condenser.

Solution was to calculate proper line size (larger than expected) between both condensers and the receiver, which would allow pressure equalization between components.

Rog

Exactly, Rog!! Symmetrical piping inbound with no one inlet being favored in flow. Oversized lines equalizing pressures to ensure gravity drain into trapped piping. I remember Phaklides' lessons almost word for word!