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multisync
10-06-2009, 05:57 PM
We have a small water chiller which has a shell and tube bundle. That water feeds a plate HE and in turn that water cools a machine.

The problem is we seem to have poor transfer from the S&T HE but good transfer from the Plate. So the shell water takes a real long time to recover and will rise even when cooling. It had a new compressor (two phasing on the contactor) and charge is weighed in.So we know the fridge side is good.

The ends of the S&T HE are welded on so we wonder how on earth would we be able to properly clean the thing. It's almost like a dirty hot water system which needs 'powerflushing'

Ideas?

chemi-cool
10-06-2009, 07:31 PM
I don't think the problem is in the S&T.

You mention that the PHE works good, it only do so if the water feed is cool, on the other hand, where can dirt come in from?

Is it a closed system? Air vents?

I would give the refrigeration unit another check up.

Grizzly
10-06-2009, 08:15 PM
Hi Multisync
There are companies that chemical clean brazed Plate Heat exchangers and Shell and tube.
Perhaps someone can point you in the direction of one near you?
Do you have binder points across the s&t ?
Grizzly

multisync
10-06-2009, 08:40 PM
I don't think the problem is in the S&T.




You mention that the PHE works good, it only do so if the water feed is cool,

primary loop at 15 secondary at 30 slowly falling


Is it a closed system? Air vents?on the other hand, where can dirt come in from?

tank has no cap. water is filthy. No treatment since day one.


I would give the refrigeration unit another check up

weighed in charge: suction low, poor heat from condenser (compared to unit next to it)..lack of cooling performance

Gary
10-06-2009, 09:36 PM
Given the water in and water out temps and the saturated condensing temp (SCT), we may be able to tell what the problem is.

multisync
11-06-2009, 01:06 PM
Hi Multisync
There are companies that chemical clean brazed Plate Heat exchangers and Shell and tube.
Perhaps someone can point you in the direction of one near you?
Do you have binder points across the s&t ?
Grizzly

We were just going to disconnect the plate HE and drop some central heating sludge shifter stuff in after sicking a pressure washer up all orifices first and giving them a blast out!

But no there are no binder or access points on the system.

chemi-cool
11-06-2009, 03:07 PM
Why not install a new S&T?

Looks like all the work around it will cost more.

Is this a Laser cutting machine?