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Grizzly
12-10-2016, 06:17 PM
Hi Guys!
"We" have a site where a chiller is still operating on R22.
Site are well aware that Legally no works can be carried out where the sealed system would be disturbed.
So the system trundles along!
The PRV's are due replacement, they are on dual manifolds.

This being the case, is their replacement allowed under the current regs?
Grizzly

Brian_UK
12-10-2016, 06:45 PM
I would assume that as the PRV is under refrigerant pressure when it is connected to the 'system'.

With that assumption made my answer would be that you cannot do it.

To quote DEFRA "You can still use your old equipment, but your technician can’t do any work that involves breaking into the refrigerant circuits".

Grizzly
12-10-2016, 07:19 PM
Ah! If only it were that simple Brian.

The Hp PRV's are on a dual manifold with which either PRV can be isolated from the system.
So technically the Valve could be changed whilst not subjected to system pressure.
Hence the Indecision!
Grizzly

Brian_UK
12-10-2016, 07:36 PM
Agreed Grizzly, but it is part of the refrigerant system.

The fact is you are actively isolating a pressurised piece of equipment so that you can remove it. There is refrigerant between the outlet of the manifold valve and the inlet of the PRV that you will be releasing when you remove the PRV.

Don't you just love those pedantic old farts? ;)

Grizzly
12-10-2016, 10:05 PM
No problem my friend.
Pedantic I like.
Because come the final decision. I will have had some guidance.

Anyone else have an opinion?
Grizzly

Magoo
13-10-2016, 03:18 AM
Grizzly.
you are between a rock and hard spot, legally clients has to have them tested and re-certified without releasing a sniff of R 22. I suggest burning off R22 vapour /destruct it as you loosen PRV
So put it back to the client for a legal opinion from their lawyers.

Quality
13-10-2016, 06:44 AM
the risk to reward ration suggests to change the prv`s and release maybe a gram or 2 rather than loose a whole load more refrigerant if they fail. By the letter of the law your not allowed to change them but a quick email to defra explaining the facts will probably allow you to

Josip
13-10-2016, 09:13 AM
Hi, all :)

Classic Catch-22

You need to repair the leak, but you cannot touch the system .... what a perfect logic ...

Best regards, Josip :)

Grizzly
13-10-2016, 06:31 PM
"Catch 22" !! is that pun intended Josip?
Also Brian, Magoo and Quality.
Thanks for the input.
I am pre-empting a customers question about the fact that his already condemned equipment.
Needs its prv's changing?
Because as we have discussed whether or not to change them is debatable!
However the PRV's on the LP side are not changeable as they screw straight into the Shell and tube evap.

Making the whole question acherdemic really!

Basically the plant is living on borrowed time and the building Landlord who is ultimately the Equipment Owner.
Does not want to pay to renew the equipment.
Cheers Guys.
Grizzly

Josip
13-10-2016, 07:45 PM
Hi, dear Grizzly :)


"Catch 22" !! is that pun intended Josip?
Also Brian, Magoo and Quality.
Thanks for the input.
I am pre-empting a customers question about the fact that his already condemned equipment.
Needs its prv's changing?
Because as we have discussed whether or not to change them is debatable!
However the PRV's on the LP side are not changeable as they screw straight into the Shell and tube evap.
Making the whole question acherdemic really!
Basically the plant is living on borrowed time and the building Landlord who is ultimately the Equipment Owner.
Does not want to pay to renew the equipment.
Cheers Guys.
Grizzly




I would assume that as the PRV is under refrigerant pressure when it is connected to the 'system'.
With that assumption made my answer would be that you cannot do it.

To quote DEFRA "You can still use your old equipment, but your technician canít do any work that involves breaking into the refrigerant circuits".



I am not sure .... intended or not ... that was the first what came on my mind ....

actually I was thinking about procedures, laws, regulations etc ... issued - in your case by DEFRA- in my country by some similar government agency .... but at the end without any common sense to be in touch with reality ...

Sometimes, I am in doubt, are in those government agencies employed right personnel:confused: ... according above Brian's DEFRA quote ... seems not ...


Best regards, Josip :)

Gibbo
15-10-2016, 03:19 PM
Hi Grizzly.
I would say you can't break into the system also as there are low pressure prv's live to the cooler. All prv's would need replacing at the same time. Would be interesting to hear what their insurance company says. Would think they have 2 choices retrofit a new refrigerant or replace the unit.
Gibbo

Rob White
15-10-2016, 04:14 PM
..

In truth the owner of the system has not just been informed
that R22 is now illegal to use, it has been on the cards for 25 years
and R22 has been severly regulated for at least 10 years.

I understand the predicament but the company has had at least 15years
notice of this and we are now nearly 2 years into the complete ban.

The guidlines as quite specific, you can't conect to a live circuit without
pulling all the refrigerant out and sending it off for destruction.
The 2 way high side PRV's could easily be argued, but the low side
has no defence.

Unfortunate but in all fairness to the authorities they have given us
25 years notice of this day.

Rob

.

Grizzly
15-10-2016, 06:04 PM
Thanks Guys!
What you are saying makes total sense only some will try and bend the rules.

I know where I stand (which is at arms length now!)
Common sense should prevail and a new chiller fitted.
The old one is 1992 and in a government occupied building.
We are not talking about small systems either 1 is 98kg and the other around 80 kg from memory.

I let you all know more when I do!
Gheers Grizzly

Magoo
16-10-2016, 12:28 AM
As an interim measure is it worth while changing the refrigerant?

james10
20-10-2016, 11:10 AM
I'd say no, rules as stated above you are not allowed to break in to the refrigerant circuit.
We wouldn't consider pumping an R22 system down and replacing a sensor or the compressor, isolating a PRV is much the same thing. I certainly wouldn't want my name on the job sheet.