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remwel
21-11-2014, 03:14 AM
Hi,

I'm currently involved in the installation of 38AP Carrier units that utilizes R410A.

Question:

Is there any pertinent document that can be used to "justify" the use of 600 and 300 psig on the test (beyond that of the manufacturers documentation)? A code perhaps? A recent ruling?


I've been using pressure test of 600psig (hi-side) and 300psig (lo-side) for the piping system for most of my R410A installations (in particular for VRF multi system - TOSHIBA SMMSi if you may) - which, is as recommended by TOSHIBA themselves.
Im being chased for such documents that was raised recently by our principals.

If anyone here knows of any, please let me know, It'll be a great help.

Thanks

frank
21-11-2014, 09:13 AM
How do you stop the low side reaching 600psig when you test the high side?

Not sure of any 'codes' or 'rulings' in the Philippines. In the UK we work to the Pressure Equipment Directive and BS EN 378, as well as the manufacturers recommendations

setrad7791
21-11-2014, 10:15 AM
You don't... When you pressurise the system it should be equal on both sides of the system, pressure test to 450psi is adequate to check pipe work welds.

Brian_UK
21-11-2014, 11:57 AM
Looking at the Standards in your country is a liitle open ended.

They recommend installation in. Accordance with the manufacturers instructions and later in the document state using 300psi for leak testing. I couldn't find specifics on stength testing though.

nike123
22-11-2014, 07:49 AM
How do you stop the low side reaching 600psig when you test the high side?

If on test are only piping, than easy!;)
They are separated.

To OP:

Here in EU strenght test is done with pressure of nitrogen equall to 1.43 times of maximum pressure expected in parts of circuit.

In my area that mean 55C of condensation temperature.
That converted to R410A saturation pressures mean around 35 Bar.
Multiply that with 1.43 and you get 50 Bar test pressure.

50 Bar = 725 PSI

If you have 2 pipe distribution system, than both pipes are "condensation" pipes and both pipes should be tested at that pressure for strenght test after brazing of network is done.

If you have 3 pipe system, than 1 pipe is always low pressure side and strength test could be adjusted to highest expected outdoor ambient temperature at standstill periods.

From my erratic memory, Mitsubishi Heawy Industries Installation manual for KX4 stated 47 Bar pressure test for all pipes. ;)

Peter_1
23-11-2014, 01:02 PM
What about the term hydrostatic pressure of 1.43 under PED?
You have the muliplier 1.43 but also 1.25!?

corresponding to the maximum loading to which the pressure equipment may be subject in service taking into account its maximum allowable pressure and its maximum allowable temperature, multiplied by the coefficient 1.25 or the maximum allowable pressure multiplied by the coefficient 1.43 whichever is the greater

Pressurizing with nitrogen at 50 bar is in fact very dangerous when something breaks during this test.
Therefore a hydrostatic test is much better but is practically seen as good as impossible.

Daikin states 41 bar as far as I remember on indoors and connecting lines.
Same for M.E. We test at 41 bar during more than a day.

nike123
23-11-2014, 02:27 PM
Pressurizing with nitrogen at 50 bar is in fact very dangerous when something breaks during this test.
Therefore a hydrostatic test is much better but is practically seen as good as impossible.

Hydrostatic test is applicable in manufacturing process. On site, not much, therefore you should use all precaution measures to avoid accidents.



Daikin states 41 bar as far as I remember on indoors and connecting lines.
Same for M.E. We test at 41 bar during more than a day.

I told you that I have erratic memory!:D

remwel
24-11-2014, 06:41 AM
Ok, it seems theres no common denominator in the field of standardization of pressure test/leak test of refrigerant system distribution piping (unit coils not included) for R410A - such reason that I was asking if theres any whitepaper outside of manufacturers recommendations that has already set these test parameters.

Now the lines (lo/hi) will be tested separately based on my statement at the top - thats fixed and it will be done (based on AS 1677.2). The thing I wanted to check is whether the 600psig on the Hi side and 300 on the Low Side is acceptable and theres a paper/code/ratification that says it is what it is and should be, coz frankly the carrier manual dont say any, so i'm lookin at other references. The only ruling we use locally here is what is as stated in pertinent HVAC codes which frankly i cant find any for the R410A systems.

:D thats what I was actually searching for.... (Y):)

Peter_1
27-11-2014, 08:47 AM
Ok, it seems theres no common denominator in the field of standardization of pressure test/leak test of refrigerant system distribution piping (unit coils not included) for R410A - such reason that I was asking if theres any whitepaper outside of manufacturers recommendations that has already set these test parameters.
...
Yes there is, we have the PED. Do a Google search for "PED 1.43"
But this PED is not applicable for your country I guess.

Contactor
15-04-2015, 04:51 PM
I always test at 55 degrees condensing equivalent temperature, so I'm with Nike 123, as I understand it EU machines are designed to 55c, but there's no way I would test at 50 bar even if the manufacturer wants it.