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lees8110
12-05-2009, 12:37 PM
Hello all,
Im still new to this scene and am Still learning about everything, and would be gratefull of any advise given. Just a few quick questions of things I am a little unsure of:
First of all, When Recovering do I recover just into the vapour valve on the recovery cylinder or liquid? Or do I swap over accordingly?
Also what is the correct way to determine the condenser operating temp? (The unit I am currently working on is a lennox package with R407c.)To work out my pressure test value when leak detecting.
Hope this makes sense, Thanks in advance for any help given

Brian_UK
12-05-2009, 11:31 PM
If you are recovering with a single hose, not doing a push/pull, then it doesn't matter which valve you use. It all ends up in the same place.

lees8110
13-05-2009, 07:54 AM
Ar Thanks Brian,
Thats what I thought it was just for piece of mind check Im doing the process correctly.

Tony
13-05-2009, 10:10 AM
Hi lees8110,


Also what is the correct way to determine the condenser operating temp? (The unit I am currently working on is a lennox package with R407c.)To work out my pressure test value when leak detecting.

To work out the minimum leak test pressure, you would use the values from the table in BS EN 378:2008, which are for UK,

High side with air cooled condenser 55C
High side with evaporative condenser 43C
Low side 32C

So you need to work out the saturation pressure of the refrigerant for those temperatures. Note use the liquid scale on your comparator.

nike123
13-05-2009, 10:53 AM
For Fujitsu R407 VRF leak test pressure is 2,94MPa for 24 hours. Change of pressure with temperature is 0,01Mpa/1K

lees8110
14-05-2009, 08:58 AM
Spot on tony thanks for that
I remember doing it now,

thanks again