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terminator
21-06-2017, 07:21 PM
Hi chaps,

I was not quite sure where to put this!

Now, we all know what best practice is when it comes to a leaking system, but I want to clarify what is actual legislation.

For the purpose of this question, lets ignore systems which are critical charge, such as vrv's etc, as there is only one way to do them properly.

Scenario:

A simple chiller cold-room on R134a is short of refrigerant - say circa 1/2 full.
You leak test and find a couple of joints / flanges leaking. These are tightened and stop leaking. You also check the rest of the system, and are satisfied there are no more leaks.
You then top up with R134a to clear the sight glass.
Is that breaking any f-gas regs or legislation?

As far as I'm aware, you are only breaking the law if you add refrigerant to a system, knowing there is a leak, or you've not found one. Obviously, even on the above, if no leak was found initially, then you'd pull the charge and pressure test to find it.

Cheers

frank
21-06-2017, 08:22 PM
How can you leak check a known leaking system properly without reclaiming the charge?

terminator
21-06-2017, 08:31 PM
..Well electronic leak detectors have been pretty damn accurate / sensitive for some time and can pick up tiny leaks (as you know). They'll pick up leaks with static pressure, you can also leak test the high side with the system running. Not sure of your point?

When carrying out f-gas checks, you don't decant the system and pressurise with ofn.

Allrounder
11-12-2017, 07:45 AM
F-Gas checks are different.
2078/9 is clear that about the correct leak test procedure. If the system has lost refrigerant you must carry out a PLT with OFN and this test must involve a timed pressure drop test. The time should be relevant to the internal volume of the system.

terminator
12-12-2017, 06:05 PM
Is that legislation though, or just best practice?

Allrounder
13-12-2017, 09:04 AM
Is that legislation though, or just best practice?

that is a very grey area

redroge
13-12-2017, 04:03 PM
If I found a system s o g I would of always gone round with a leak detector first whether it was the old flame on 22 or an electronic , pressure testing tells you there is a leak you've still got to find it !
I once had a small 410a split that held less than 1kg it took six months to loose enough to cause a problem , the leak only showed when in cooling mode on the outdoor suction flare , when it was in heating mode there was no sign of a leak , when it was pressure tested it held its pressure.

terminator
18-12-2017, 09:17 PM
If I found a system s o g I would of always gone round with a leak detector first whether it was the old flame on 22 or an electronic , pressure testing tells you there is a leak you've still got to find it !
I once had a small 410a split that held less than 1kg it took six months to loose enough to cause a problem , the leak only showed when in cooling mode on the outdoor suction flare , when it was in heating mode there was no sign of a leak , when it was pressure tested it held its pressure.

Yes,

I've had hot / cold leaks - they can be a right pain to find.

cadwaladr
19-12-2017, 01:51 AM
Sometimes when you have a problem leak you wish you could throw it in a swimming pool !

Rob White
19-12-2017, 06:41 PM
.

Dot gov site states.............

https://www.gov.uk/guidance/f-gas-in-refrigeration-air-conditioning-and-fire-protection-systems#check-for-leaks


If you find a leak

If a leak is found during a check, you must repair it and repeat the test within a month to check the repair worked.

It does not go into too much detail as to what constitutes a repair?

Rob

.

terminator
19-12-2017, 07:28 PM
.

Dot gov site states.............

https://www.gov.uk/guidance/f-gas-in-refrigeration-air-conditioning-and-fire-protection-systems#check-for-leaks


If you find a leak

If a leak is found during a check, you must repair it and repeat the test within a month to check the repair worked.

It does not go into too much detail as to what constitutes a repair?

Rob

.

Which most companies get around by leak testing again within an hour - they don't come back a day / week / month later.