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Hi all,
Given the current climate (financial..), i've been asked to carry out the fitting of new PRV's to a couple of chillers. Whilst i have no problem undertaking the work, my main background is on the commercial side. The chiller has 2 circuits with 87/80kg of gas. The only problem i do have is estimating the ammount of OFN that would be required to pressure test the system.
Would anyone know an appoximate figure of OFN required to pressure test a circuit containing 87kg..?
With thanks,
KD
KD.
What are you proposing to do to the PRV's.
You state pressure test, surely you mean leak test your joint onto the system?
It is not a requirement to actually lift a newly fitted PRV.
In fact doing so may well cause that prv to fail.
If I am reading you wrong and you are wondering how much to leak check.
I would try and isolate the High side to reduce the amount required. because on a chiller that size you would logically need at least a large size K or W (BOC sizes).
Grizzly
Grizzly,
Thanks for your reply. Yes, sorry, I meant leak-test.
Just looking for a ballpark figure for an estimated amount of OFN to undertake the leaktest. As I have 2 chillers (four circuits) to fit new PRV's too. As part of the written scheme for the chiller, we are required to change the low-side PRV also. Point taken and already considered about isolating the high-side.
My background is mainly light to medium commercial so a small 10L OFN normall does me just fine.
For general interest the manufacturer (York) quoted £6,700 to fit new certified valves which were a further £800. Nice work if you can get it....
I am always surprised as to what differing Insurance surveyors expect, especially as they apply pressure regs to all prv's on chillers.
When some are fitted to comply with en378.
As a rule lp does not require changing.
In fact if it's worth questioning upon what basis the lp side is being changed.
Some written schemes as I say are applied incorrectly.
Grizzly
Hard to say how much, if in doubt give them an open price if quoting and be honest...tell them you cant estimate!
I normally just go on experience for a rough guide, and if in doubt i ask at a local supplier..climate etc if i can bring some of the cylinders back if i dont need them. Normally if your nice they can be ok with it.
Jay
2 W size bottles from Boc should be ample remember to check the MWP Of the evap and stay 2 bar below (per circuit)
I usually use a big bottle(size N I think) per system, should be plenty...