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jmc
11-01-2012, 06:54 PM
Hello Refrigeration Engineerers

I would really appreciate some advice please on some refrigeration pipework that I have come across.
We attended a clients site today to repair a suspected refrigerant leak. The unit is a Lennox DX system running on R407c installed approximately 10 years ago. We have found that all the copper refrigerant pipework (5/8 & 1 3/8) is seamed not seamless (as I would expect) and that all the joints are soft soldered.
I am assuming that all this pipe work is not refrigerant specification? The pipe work quality is fantastic but we are a little reluctant to strength test to 31b.
I have been looking for legislation to pass onto our clients to show that seamed copper and soft solder are not the way forward but have not come up with the conclusive proof necessary.
In your opinion should I tell him that unfortunately it is necessary to condemn all of his pipe work ( what legislation justifies this) or as it has been satisfactory for the last 10 years am I being overly cautious?

stufus
11-01-2012, 07:46 PM
Not sure of the exact legislation .Are you sure it's soft solder ? not silver solder?
But the system make up has to conform to the F-gas protocol surrounding pressure and strength testing and there for if it fails ,there is no two ways about it .....It's got to go !
All copper pipework and associated copper materials
must conform to the requirements of BS2871.
Part 2 being of suitable quality for refrigerants.
Cheers
Stu

jmc
11-01-2012, 09:00 PM
Hello Stu, thanks for the quick reply.
I am sure that it is soft solder that's been used as its still bright and when we passed a small file over a run of it it filed easily unlike silver solder or eutectic.
I can see that BS2871 part 2 refers to suitable qualitymaterials for refrigeration installations (now you have pointed me in the right direction) but isn't that legislation superseded by EN378 ?
I have read somewhere else on the forum that refrigerants can react with the lead in soft solder over time and thus creates leaks?

Thanks again Stu

Grizzly
11-01-2012, 09:22 PM
Stu is on the right track there jmc.
Below is from EN378 (Which is law).
g) Tin and lead tin alloys
Tin and lead tin alloys may be corroded by halogenated refrigerants and shall not be used unless their
compatibility has been proved by test or experience.
NOTE 4 Copper free lead antimony or lead tin alloys may be used for valve seats.

The material of the component shall be suitable for the intended temperature and pressure range and in
combination with refrigerating systems and heat pumps as specified by the manufacturer of the
refrigerant systems and heat pumps. The relevant standards have to be considered.

Pipework must comply with EN378 and EN 14276-2 (Don't have that to quote)
Your only dilemma should be how you are going to break the news to your customer.
However you say it you have to at least inform him of your doubts.
If you are correct then that install is illegal and and until you inform the equipment owner you could in-part be held responsible for any liabilities resulting from that equipment failing.


Hey! look on the bright side you are a professional and as such know what is required and is not!


Pass it on and give him the problem. Many customer may not like what an engineer has to say.
But not many choose to ignore legal requirements.


Grizzly

jmc
11-01-2012, 09:38 PM
Thanks for your input Grizzly, I will show them the seamed copper and explain about the soft solder .
I don't want them to feel as we are picking faults because we are looking for extra work , fortunately we have more work than we can deal with at the moment anyway.

stufus
11-01-2012, 09:43 PM
Nice one Grizzly
Keeping up with exact legislation was never one of my strong suits,tend to rely more on common sense.
I'd rep you but as usual I have to spread the love.
I'll see you right when I get my glasses.:cool:
@ JMC
Looks like you'll just have to bite the bullet and bear the bad news ,do it in writing also and get the client to sign it (when he calms down).:)
Best of luck !
Cheers
Stu

The Viking
11-01-2012, 09:47 PM
As the bear said...

Also, more likely than not those pipes are water pipes and therefore metric.
If you cut a section out and show the customer, the wall thickness is visibly thinner than a fridge pipe and the pipe will not fit well in to a flare nut.
Just a thought...

r.bartlett
11-01-2012, 09:59 PM
Latent defect.

Grizzly
11-01-2012, 10:12 PM
Latent defect.

You are to knowledgable for me RB.
I had to google that one!

latent defect n. a hidden flaw, weakness or imperfection in an article which a seller knows about, but the buyer cannot discover by reasonable inspection. It includes a hidden defect in the title to land, such as an incorrect property description. Generally, this entitles the purchaser to get his/her money back (rescind the deal) or get a replacement without a defect on the basis of "implied" warranty of quality that a buyer could expect ("merchantability"). Even an "as is" purchase could be rescinded if it could be shown the seller knew of the flaw

jmc
11-01-2012, 10:39 PM
Thanks everybody.

Magoo
11-01-2012, 11:38 PM
The plant is an identifiable health hazard and enviroment risk, condem and lockout system/s. That will cover you under OH&S regulations.

Brian_UK
11-01-2012, 11:45 PM
You could also point out to your customer that they may have insurance issues now that the 'problem' has been identified.

Greengrocer
12-01-2012, 12:12 AM
Seamed pipe-work & soft solder smacks of a plumber & non-qualified install. Can the client remember who installed it originally?
They probably got the pipe-work from the local B&Q or Wickes. It's amaizing it's lasted 10 years without any major problems. Peel back the lagging & see if you can find any markings on the pipe-work. If it's marked in mm / metric then it's definitely heating / sanitary grade & not suitable for use in an A/C or fridge system.

Humm. You said it was seamed pipe-work. If memory serves even our UK heating copper pipe-work isn't seamed. The only place I've seen seamed copper pipe-work is on the continent. Is this by any chance an Italian, French or Spanish restaurant or chain store?

al
12-01-2012, 07:34 PM
Pipe work has, if my soozled cells are right, been stamped with the relevent BS/EN number for a good few years, this may be metric pipe out of italy and may be suitable, only way to confirm if it is not stamped (fittings should also be stamped), is to cut a piece out and have it tested.

Al