leak testing

[pentond1]

I have been informed that you should not pressure test a refrigeration system system using a nitrogen bottle even if has a requlator via a manifold set which has a sight glass, anticipated nitrogen pressure 6 - 20bar.

[jcook1982]

I've heard to use Helium becuase the molecules are smaller which will make the Leak easier to be detected. Never heard that nitrogen was bad. Only that you should not pressure test over 350psi

[nike123]

I have been informed that you should not pressure test a refrigeration system system using a nitrogen bottle even if has a requlator via a manifold set which has a sight glass, anticipated nitrogen pressure 6 - 20bar.


It is correct!
Nitrogen is right gas for that purpose. To use manifold set with which has sight glass is also normal practice, if you are not exceeding pressure rating of that manifold set and if you are using pressure reducing valve, adjusted to max allowable pressure of that part of circuit you are testing and not exceeding pressure rating of weakest part in setup. That part could be easily your manifold gauges with sight-glass. Use safety goggles.

[nike123]

I've heard to use Helium becuase the molecules are smaller which will make the Leak easier to be detected. Never heard that nitrogen was bad. Only that you should not pressure test over 350psi

Max pressure depends on maximum allowable pressure of weakest part under testing.
If you have heat pump on R410 you have higher working pressures than 350PSI.

[Mozambezi]

I would have look on system info, usually on back panel. It says maximum pressures. For R410a do 30 bar, R134a do 20, other 25. If here is pitch hole I do higher pressure... up to 5 bar more.
If pressure test negative, I would recommend to have chat with customer and put UV and Sealant into system... usually helps.

[Brian_UK]

I would have look on system info, usually on back panel. It says maximum pressures. For R410a do 30 bar, R134a do 20, other 25. If here is pitch hole I do higher pressure... up to 5 bar more.
If pressure test negative, I would recommend to have chat with customer and put UV and Sealant into system... usually helps.NO, if pressure test negative then fix the leak properly.

Adding any form of sealant is likely to cause problems unless you know something better than usual products.

[brunstar]

there is a new pressure testing regulator that you can get that should be used now, no sight glass should be used with high pressure nitrogen anymore.
The new manifold has a braided hose and it is heavy duty to withstand higher pressures without explosion on failure..
this device weighs about 8kgs and is new common practise.

[bill1983]

come on guys, the question was about using a manifold with a sight glass to pressure test. it has always been recommended that you do not ever use a sight glass equipped manifold for pressure testing due to the unknown condition of the glass. it would be bad enough if the glass broke under normal system pressure, but if you get into the habit of using your normal manifold set to pressure test even the low side of the system then one day you will forget and "quickly" pressure test the high side. the same goes for using a faulty nitrogen regulator or gauges. we all know someone who has done it. but we probably also know someone who had a near miss as well.
it may seem a bit nannyish but don't do it and don't advise anybody that it is ok to do it for a short time.

[Brian_UK]

Well said Bill1983, succinct and to the point. Thanks.

[nike123]

there is a new pressure testing regulator that you can get that should be used now, no sight glass should be used with high pressure nitrogen anymore.
The new manifold has a braided hose and it is heavy duty to withstand higher pressures without explosion on failure..
this device weighs about 8kgs and is new common practise.

I don't see why you should not use gauge manifolds with sight glass with which you measuring your system pressures, for pressure test, who is same or slightly elevated as operating refrigerant pressure, if they are rated for higher pressure than test pressure.
Of corse that I mean that pressure regulator should be used at nitrogen botle to reduce pressure from botle to test pressure.

[bill1983]

the problem isn't the pressure you intend to test at, its the pressure you might release into the manifold. most of us i would hope are skilled enough to be able to do this safely, but because of the potential risk shouldn't do it anyway.

[frank]

We've had this discussion before.

Personally, I consider the manifold set to be safe upto the maximum pressure shown on the dial, otherwise, the manufacturer would not release the product into the main market place, considering their responsibility if something went wrong.

In this day and age of litigation driven thinking, every responsible manufacturer would build some safety factor into their product, even considering such things as wear and tear on the sight glass.

I've yet to see some scientific evidence about sight glass failure to convince me otherwise.

Scaremongering, that's what I say ............

[nike123]

the problem isn't the pressure you intend to test at, its the pressure you might release into the manifold. most of us i would hope are skilled enough to be able to do this safely, but because of the potential risk shouldn't do it anyway.

Sorry at my hair splitting, but I don't see how you could release higher pressure in to manifold if you have reduced pressure at test pressure value before manifolds at pressure reducing valve.

[nike123]

We've had this discussion before.

Personally, I consider the manifold set to be safe upto the maximum pressure shown on the dial, otherwise, the manufacturer would not release the product into the main market place, considering their responsibility if something went wrong.

In this day and age of litigation driven thinking, every responsible manufacturer would build some safety factor into their product, even considering such things as wear and tear on the sight glass.

I've yet to see some scientific evidence about sight glass failure to convince me otherwise.

Scaremongering, that's what I say ............

Good said Frank. You have one Paulaner Hefe-Weizen from me.;)

[bill1983]

i agree with you both, but it doesn't change the fact that the manifold is not built to be safe at the maximum pressure that the nitrogen cylinder can supply, nor are the gauge lines. like i said we are probably safe enough to do it, but do you want to be there when it goes wrong? yes the problem is litigation, the rules are now made for the less intelligent but they do apply to all. the choice is yours.

[bill1983]

as regards the hair splitting nike, dont worry about it, its what the forum is for. it doen't matter what you have set the regulator for, it matters that it COULD release more pressure than the manifold,lines, sight glass can take.

[nike123]

i agree with you both, but it doesn't change the fact that the manifold is not built to be safe at the maximum pressure that the nitrogen cylinder can supply, nor are the gauge lines. like i said we are probably safe enough to do it, but do you want to be there when it goes wrong? yes the problem is litigation, the rules are now made for the less intelligent but they do apply to all. the choice is yours.

I think that you are not reading carefully what I wrote my friend:


how you could release higher pressure in to manifold if you have reduced pressure at test pressure value before manifolds at pressure reducing valve

I dont see how! Could you elaborate?

[bill1983]

if i'm reading you right nike, then you are saying that if you set the nitrogen regulator to a safe pressure for example 100psig then you will not then release any more pressure into the manifold than that. therefore the operation is safe. is that correct?

[nike123]

if i'm reading you right nike, then you are saying that if you set the nitrogen regulator to a safe pressure for example 100psig then you will not then release any more pressure into the manifold than that. therefore the operation is safe. is that correct?

Yep, that is correct!

When I set pressure reducing valve, I first put cap at valve outlet and then adjust pressure to test pressure value, and after that, I remove cap and connect gauge manifold! So there is no way that pressure higher than set on pressure reducing valve could reach gauge manifold.

[superswill]

a good read on this topic

http://www.ior.org.uk/ior_/images/pdf/se/Good%20practice%2024%20leak%20tightness%20testing.pdf

[bill1983]

ok. in an extreme scenario which is what the rules are now made for regardless of how little sense they make to you, let us say that you have to leave the nitrogen bottle unattended. you shut down the bottle before you leave the plant. you then go to the other end of the system you are leak testing and begin to look for leaks. you are leak testing for maybe 15 minutes max, during which time you judge that it is safe to leave the nitrogen unattended because you have chained it to a pillar to prevent it from falling over. while you are away, somebody sees the nitrogen and being curious decides to have a closer look. he wonders what will happen if he turns the regulator knob. nothing happens of course because you sensibly isolated the cylinder valve just in case the regulator catestrophically fails. however this curious person just happens to be carrying a multitool and can open the cylinder valve. he does this and winds the regulator fully open. now if the manifold valves are open, he will burst the lines first and receive lacerations to the face and torso from the whipping action ofthe burst lines. however if the valves are not open where is the weak point of the manifold. oops remeber when you dropped it while you were putting it away. it didn't seem to damage it, but what if it caused the sight glass to crack . not enough so you could see it, but just enough to set up a weakness. with 35 bar behind it, and an idiot in front of it you can see what could happen. this is the person for whom health and safety rules were written. this is a unliokely scenario i know BUT the rules are written for just such an event. sad but very true. i can only presume that this is not yet the case in sunny Split?

[bill1983]

thanks swill? item 12 on the procedure list will make the test safer but only muppet proof if you take the line with you or lock it away.

[frank]

I follow the arguments, but, if you ensure that the bottle regulator maximum pressure will not exceed the maximum pressure of the gauge set you are using (common sense I know), then the possibility of an unforeseen accident should be eliminated.

[nike123]

ok. in an extreme scenario which is what the rules are now made for regardless of how little sense they make to you, let us say that you have to leave the nitrogen bottle unattended. you shut down the bottle before you leave the plant. you then go to the other end of the system you are leak testing and begin to look for leaks. you are leak testing for maybe 15 minutes max, during which time you judge that it is safe to leave the nitrogen unattended because you have chained it to a pillar to prevent it from falling over. while you are away, somebody sees the nitrogen and being curious decides to have a closer look. he wonders what will happen if he turns the regulator knob. nothing happens of course because you sensibly isolated the cylinder valve just in case the regulator catestrophically fails. however this curious person just happens to be carrying a multitool and can open the cylinder valve. he does this and winds the regulator fully open. now if the manifold valves are open, he will burst the lines first and receive lacerations to the face and torso from the whipping action ofthe burst lines. however if the valves are not open where is the weak point of the manifold. oops remeber when you dropped it while you were putting it away. it didn't seem to damage it, but what if it caused the sight glass to crack . not enough so you could see it, but just enough to set up a weakness. with 35 bar behind it, and an idiot in front of it you can see what could happen. this is the person for whom health and safety rules were written. this is a unliokely scenario i know BUT the rules are written for just such an event. sad but very true. i can only presume that this is not yet the case in sunny Split?

That scenario is like you say that someone in office could kill himself with pencil?
And legislation is not holy cow that we "believers" should not reexamine some of rules put by some clerk who actually newer has been at field and now write rules for field peoples.
Have you ever been in shipyard? If everyone included in shipbuilding strictly follows the rules about safety etc.. ship would never see the day of baptizing.

Don't you thing that is also same chance to blow out for damaged pressure gauge as it is for sight glass, and that exploded pressure gauge could make same damage as sight-glass blowing.
It is our common sense and education what keeps us safe, not some legislation.

[pentond1]

Thank you for your replies - if the manifold gauge set with sight glass should not be used what is the procedure when pressure testing with nitrogen with fitted sightglass on the compressor/refrigeration systems (407c/R22).

[nike123]

Thank you for your replies - if the manifold gauge set with sight glass should not be used what is the procedure when pressure testing with nitrogen with fitted sightglass on the compressor/refrigeration systems (407c/R22).

Good point!
Answer is probably " sight glass on compressor is not that much endangered as your gauge manifold set".;)

[Billy Ray]

That scenario is like you say that someone in office could kill himself with pencil?

Thats pretty much the best one i've heard for a long while!!

I agree.

My line manager would probably do that as well!!

The key to this is the right man for the right job!!

& that man needs training & buckets of experience!!!

& that man could be a female!!!!

[nike123]

& that man needs training & buckets of experience!!!

& that man could be a female!!!!

I would be pleased to work with that female man!
But females somehow don't like to carry around bottles of acetylene around and be in blast freezer rooms at -40°C more than 2 seconds.;)
Could be that they are smarter than mans.

[Brian_UK]

Thank you for your replies - if the manifold gauge set with sight glass should not be used what is the procedure when pressure testing with nitrogen with fitted sightglass on the compressor/refrigeration systems (407c/R22).Test pressure could be lower on those two gases compared with R410a so maybe not such a problem.

Unless of course your worst case scenario takes over again ;)

[Temprite]

I follow the arguments, but, if you ensure that the bottle regulator maximum pressure will not exceed the maximum pressure of the gauge set you are using (common sense I know), then the possibility of an unforeseen accident should be eliminated.

I have had the sight glass blow out on a set of gauges where the reg could not exceed the max working pressure of the gauges.

Admittedly it was my own fault.

Had the gauges hooked up and closed, connected reg and opened valve on bottle. Last person that used reg had left it fully open, momentary inrush of pressure through reg was enough to break glass and send it into my lip.

I always check the reg first and make sure it is closed now.

[bill1983]

QED unfortunately

[frank]

I have had the sight glass blow out on a set of gauges where the reg could not exceed the max working pressure of the gauges.

Admittedly it was my own fault.

Had the gauges hooked up and closed, connected reg and opened valve on bottle. Last person that used reg had left it fully open, momentary inrush of pressure through reg was enough to break glass and send it into my lip.

I always check the reg first and make sure it is closed now.

You can't buy experience.

[glenn1340]

I would be pleased to work with that female man!
But females somehow don't like to carry around bottles of acetylene around and be in blast freezer rooms at -40°C more than 2 seconds.;)
Could be that they are smarter than mans.


"I would be pleased to work with that female man! "
....anything you need to tell us nike? we`re all here for you;) now, just where did I put my wig.

Glenn

[Mozambezi]

NO, if pressure test negative then fix the leak properly.

Adding any form of sealant is likely to cause problems unless you know something better than usual products.

Brian U're 100 percent right. Here are no good sealants in HRP.

Let's imagine A/C VRV with kg R-410a.
U're contractor, got quota for recharging the system /short of gas/...
After 2h on 43bar no leaks found and you checked all joints, or most of them... u doing VAC and in another 2h pressure comes up from 4 Torr to 6... Test kit is OK.
Well. Technically OFN test positive, but ...
What u would recommend me to do when I've got max 20h to complete a job? /please be constructive/

:off topic:

[Slatts]

Rules are for the guidance of the wise and the protection of fools.
When I started in the trade in the late 70's we'd put a 5/8" MF to 1/4"MF reducer in the nitro bottle and hook it up to the system to be tested or purged with a 1/4" copper line.
We'd crack the bottle valve carefully (if you can use that word in that context).
Now I'm older and I hope wiser, I won't go near a nitro bottle without a proper nitro reg. I always close the reg and open my manifold valves before opening the bottle.
I've never owned a set of gauges with a sight glass and don't really see the need.

[nike123]

"I would be pleased to work with that female man! "
....anything you need to tell us nike? we`re all here for you;) now, just where did I put my wig.

Glenn

You know what part of female man I was thinking!:mad: :D

[El Padre]

Its reassuring to see the promotion of sexual equality in our industry.
Good Work!!
Regarding the pressure testing I agree with Nike and Frank.

[rachid269]

hi guys.

i've taught that the strengh test has to be 30% more of the normal pressure that soport the wakeast device on the system.

leak test > is 1 time of the normal pressure

strengh test> is 1.3 of the weakeast device on the system.

thank you guys,,,

[Peter_1]

I think most EU posters forget EN37-2008, pressure testing with an inert gas is compulsory..in fact since 2000.
RAchid269, where you found 1.3?
And 1.3 of what?
I have 1.1 of ps (EN378-2008-2 - 6.3.3.)
And even then, it all depends in what category your installation is falling.

Mozambezi, if in the Eu, fact you only have 20 hours for the job doesn't matter. You have to comply with the EU- regulations, even if it takes 20 days.
But I know, you and yuor clients will have limits but it's up to you to decide if you don't wanna follow the rules.

Pentond, your compressor sump and the sightglass are on the Lp of the system, which can be pressurized at a lower pressure (En378-2008-2 - 6.2.1.1. - Table 2)

[Plank!]

The company I work for does not allow any pressure testing with a charging manifold.
All pressure testing MUST be carried out using a pressure relief valve.
Hence we have steel pressure testing manifold with an assortment of 1/2" and 3/8" ports, to this a calibrated gauge and a vent valve is fitted - the rig is hydraulic tested at 200Bar. For normal testing a CVP valve is fitted into this manifold and set to start venting 2 bar above test pressure.
For pressure testing CO2 systems (@77Bar +) the CVP is blanked off and a seperate pre-set relief valve fitted.
All hoses used for pressure testing are 6 or 10mm braided SS or 6mm SS tube.
Why take a chance with pressure testing?
Nitrogen regulators can fail - normally due to the diaphram being reverse pressured when changing the nitrogen bottle without first valving the regulator off from the rest of the system and venting it, this CAN cause the regulator to pass, perhaps only by a small ammount, but enough to over pressure a system or charging manifold/hose. Always close the nitrogen bottle as soon as test pressure is reached.

To the people who boast about using minimal equipment, I hope you are still here to boast of it when your equipment fails during a test. Why take the chance?
The pressure test guidelines in BS-EN378 should be regarded as the MINIMUM standard required, not some inconvieniance that you should do everything to bypass. Too many people have already died pressure testing systems, don't add your name to the list.

Regards
Steve

[Mozambezi]

I think most EU posters forget EN37-2008, pressure testing with an inert gas is compulsory..in fact since 2000.
RAchid269, where you found 1.3?
And 1.3 of what?
I have 1.1 of ps (EN378-2008-2 - 6.3.3.)
And even then, it all depends in what category your installation is falling.

Mozambezi, if in the Eu, fact you only have 20 hours for the job doesn't matter. You have to comply with the EU- regulations, even if it takes 20 days.
But I know, you and yuor clients will have limits but it's up to you to decide if you don't wanna follow the rules.

Pentond, your compressor sump and the sightglass are on the Lp of the system, which can be pressurized at a lower pressure (En378-2008-2 - 6.2.1.1. - Table 2)


Pressure test use to be 1.3 PS in DIN /German standart/.

U are saying .... as long as it takes... Here is a yesterdays example from real life.
My company A quoted for 4h of OFN leak test. Company B quoted 3h for leak test. Job was compressor change. Company B won.

[Peter_1]

If you're in the UK, then you have to follow the UK rules and not DIN rules and even more specific the EN rules.

EN378-2008 even states that national rules are no longer valid.
So I doubt your statement about DIN rules and especially in the UK.

If you have to change a compressor, I don't think 1 hour difference in pressure testing will not make a difference in winning the job. And if you do it it now 3 hours or 4 hours, it will not better strength or leak tested.

Again, it's up to you to follow the rules or to neglect them.

But saying this, in the new EN378-2008, we no longer find any(!! ) requirements about pressure testing and vacuum procedures. Those were detailed explained in the old EN378-2000.
Someone noticed this already?

[jbiasutti]

One of the problems with single stage pressure regulators is that the set pressure of the regulator depends on the pressure inside the nitrogen cylinder.

As the pressure in the cylinder drops the outlet pressure of the regulator increases and the flow of gas from the regulator also increases.

Thus it is possible to set the nitrogen pressure at a safe level and if there is a leak in the system that causes the bottle pressure to drop results in higher pressure.

I have seen a system where a system was put on a nitrogen purge with a low flow of nitrogen. The system was left for some hours and then the outlet of the system closed. This resulted in much higher pressure in the system than anticipated.

[sumsor]

I mostly install city multy systems in commercial buildings. On the 410a systems the test pressure is 600 psi and I use a high pressure gauge and flared copper connections. A gauge manifold with sight glass is not only a safety risk, but also tends to leak after a few tests.

[Slatts]

For serious pressure or vacuum testing, you can't go past copper and flares. Flexible gauge lines are just another possible point of failure.
If you have an open compressor (pretty unlikely on R410a) and you have to pass a low vac test, I'd valve it off from the test. Shaft seals are meant for a positive pressure and often don't hold a high vacuum.

[Greengrocer]

I mostly install city multy systems in commercial buildings. On the 410a systems the test pressure is 600 psi and I use a high pressure gauge and flared copper connections. A gauge manifold with sight glass is not only a safety risk, but also tends to leak after a few tests.

Is not a requirement when pressure testing (strength testing) to those high levels to evacuate the building? I seem to remember seeing something about this somewhere but can't remember at present.
The point being that if a brazed joint failed at 600psi it could take someones head off.

[Silhouette]

Our insurers witness pressure tests and we have to evacuate the area where the system is installed and barrier it off and include signage to restrict access!

[icecube51]

its like frank says, "you cant by experience" but whe pay dearly for it.

Ice

[Mozambezi]

Well...

Following Mitsu or Daikin Intallation manuals we need to keep pressure for 24h on comissioning...
in 2-3h some engineers could find that pressure drops or raises and depends up to air/ sun temperature.
True leak test is VAC test... Left pomp through the night and in the morning take VAC for 2-3h... if holds 4-6 Torr, then OK... If more.... use sealant, if more then 10, then put CO2 + Refrigerant or OFN + HE... or if system compicated, use distilated water...

P.S.: DIN standard is in base of EN and is more demanding. Belive me /have Tuv nord certificate for pressure test./

[Mozambezi]

P.P.S.: For companies with long service contract /5 or more years/ would recommend to keep equipment gas register and monitore leaks...
I would say loss 10% of charge in a year is bottom line... 2% is optimistic for new Daikin VRV systems...

[Brian_UK]

Well...

Following Mitsu or Daikin Intallation manuals we need to keep pressure for 24h on comissioning...
in 2-3h some engineers could find that pressure drops or raises and depends up to air/ sun temperature.
True leak test is VAC test... Left pomp through the night and in the morning take VAC for 2-3h... if holds 4-6 Torr, then OK... If more.... use sealant, if more then 10, then put CO2 + Refrigerant or OFN + HE... or if system compicated, use distilated water...

P.S.: DIN standard is in base of EN and is more demanding. Belive me /have Tuv nord certificate for pressure test./I intrigued to know how a pressure test of 1 bar can prove that a system is leak free.

Also what sealant do you use ?

[expat]

Also what sealant do you use ?


He uses distilled water of course:)

[Slatts]

Well...

Following Mitsu or Daikin Intallation manuals we need to keep pressure for 24h on comissioning...
in 2-3h some engineers could find that pressure drops or raises and depends up to air/ sun temperature.

Read, some engeneers couldn't solder well enough to hold a pressure test for 2 -3 hours.:o

True leak test is VAC test... Left pomp through the night and in the morning take VAC for 2-3h... if holds 4-6 Torr, then OK...
If only hold 4 to 6 Torr for 2 to 3 hours, pressurize the system with nitro and find then fix the leaks.
If the system is dry and sealed it should hold 0.5 Torr (500 micron) for 24 hours.


If more.... use sealant, if more then 10, then put CO2 + Refrigerant or OFN + HE... or if system compicated, use distilated water...

P.S.: DIN standard is in base of EN and is more demanding. Belive me /have Tuv nord certificate for pressure test./

Distalated water? Sealant? Hu?
Solder your pipes in properly.
inspect the welds with a mirror and torch, then pressure test with nitro. If the system holds the pressure test, vac it to 500 micron and if you have to do a vacuum test. If you've been putting "distalated water" in the system, don't expect it to pass a vacuum test.


P.P.S.: For companies with long service contract /5 or more years/ would recommend to keep equipment gas register and monitore leaks...
I would say loss 10% of charge in a year is bottom line... 2% is optimistic for new Daikin VRV systems...

How is any gas loss in a newly installed and commissioned system acceptable?
If your people are competent and the system has been pressure tested and vacced properly there should be no leaks in the first 12 months of operation.
I can only assume that something has been lost in the translation.

or have I missed something here?

[nike123]

I think both methods are good methods (vacuum test and pressure testing).

With pressure test you have high pressure difference at sides of leak (leak rate is high) and low accuracy (resolution) manometers to test leak and also influence of temperature change on test gas pressure.

On the other end, you have small pressure difference (1 bar) between sides of leak (leak rate is small but still present), but very precise and sensitive instrument to detect that small leak rate, and very, very, very small influence at reading of temperature change of gas remained in vacuumed pipes.

To me it looks like both methods are equally good with one key difference. If some welds are mechanically weak, pressure test will make them to open and leak but vacuum test will never disclose them.

That is why I will always make first pressure test and then vacuum test on systems where welds are involved.
On split systems with pipes in one piece, only vacuum test is sufficient.

That is my 2 cents.

Also, keep in mind this:
http://www.refrig.com/bigblumanual3.html#EVERTHING%20LEAKS

[Peter_1]

To me it looks like both methods are equally good with one key difference. If some welds are mechanically weak, pressure test will make them to open and leak but vacuum test will never disclose them.

That is why I will always make first pressure test and then vacuum test on systems where welds are involved.
On split systems with pipes in one piece, only vacuum test is sufficient.

According EN378-2008, all systems must pass a strength test at a predetermined pressure and a leak test. Both are serving a different purpose. It's not leak testing or pressure testing, it's and ..and

[nike123]

According EN378-2008, all systems must pass a strength test at a predetermined pressure and a leak test. Both are serving a different purpose. It's not leak testing or pressure testing, it's and ..and

Peter, my country is not in EU (and probably will not be) and we are not obliged here to follow that norms. Our norms are still harmonizing with EU regulation.

I wrote that from perspective of common sense and not from perspective of norms and regulations.


That is my 2 cents.

Also, in mini split systems with pipes from one piece, Indoor and outdoor unit is already tested and comes with certificate and pipes are tested and comes with certificate so there is nothing to strength test.

[Peter_1]

Peter, my country is not in EU (and probably will not be) and we are not obliged here to follow that norms. Our norms are still harmonizing with EU regulation.

I wrote that from perspective of common sense and not from perspective of norms and regulations.

Ok, you're right


Also, in mini split systems with pipes from one piece, Indoor and outdoor unit is already tested and comes with certificate and pipes are tested and comes with certificate so there is nothing to strength test.

OK, but only valid outside the EU.

[Peter_1]

Peter, my country is not in EU (and probably will not be) ..
Croatia is negotiating to join the EU, isn't it?

[nike123]

Croatia is negotiating to join the EU, isn't it?

Yes, but for now, that is at hold! And date of joining are continually postponing from mostly political reasons (and EU should stand for European economic union) and our goverment incompetence. At least, that is how I see it.

[brunstar]

:eek::rolleyes:

it actually worries me about some of the work that is being carried out in different countries, i can see why a lot of countries have not changed to 410A either as i don't think the techs would be able to carry out the work.

If you are a fully qualified refrigeration engineer and have not been bred into it, the work to be carried out on installations should be of some similar quality, sealants and Co2 being used, hmm, if a strength test and leak test is not being carried out properly, i would hate to see what is going to happen when a VRV Co2 system is installed....hmmmm... i am scared and can see why there are so many leaks and problems out there and need for regulations!!!

[Peter_1]

A CO2 VRV, what's that?

[brunstar]

it is a Variable Refrigerant Volume, multi system running on CO2 gas.

[Peter_1]

What brands are already selling a CO2 VRV in the EU?
None I suppose.

[nike123]

I dont know is any in Europe.

Daikin: The global supplier is presenting a world premiere, as its latest VRV (Variable Refrigerant Volume) model is now using the natural refrigerant CO2. It is optimised for heating function. The outside unit features a heating capacity of 31.5 kW for heating, and 28 kW for cooling. Daikin has applied a new refrigeration cycle technology with a swing compressor and a newly developed heat exchanger. The CO2 model is compatible with all VRV control and management systems.


http://www.r744.com/articles/2008-10-20-chillventa-a-showcase-for-co2-(part-3).php

[john tucker]

you should only use OFN for this pressure testing

[Slatts]

you should only use OFN for this pressure testing
OK John. I'll bite. What's OFN?

[nike123]

OK John. I'll bite. What's OFN?

Oxygen Free Nitrogen

[Slatts]

Oxygen Free Nitrogen
Thanks nike.
Over here in my neck of the woods, we still use industrial dry nitro.:o