R402 - big problem

Duniek · 08-31-2006, 04:20 AM

hi
Sometime ago I bought a 5 kg of R402a refrigerant
I charged SS and I have a -35*C on evap at suction pressure 0 bar
and discharge pressure at 15 bar ?
WTF ?

jinu117 · 08-31-2006, 04:24 AM

15 bar doesn't sound too out of line?
-35c evap and 0 suction sounds bit strange though.
Check the gauge first?
Also... where did you get 5kg of R402a? I didn't know such quantity existed?

Blaster · 08-31-2006, 06:20 AM

is it r402a or r402b ?

kayl · 08-31-2006, 06:29 AM

you may have a restriction/ too short capillary line/ moisture list goes on.

Quasi · 08-31-2006, 06:39 AM

If it wasn't the first gas you ever put in the system, meaning it ran fine with another gas - then it sounds like someone sold you bad 402 - maybe a mixed recovery or air in it.

How about vacuum? triple evac? Bad vacuuming would do the same thing

aasmaukr · 08-31-2006, 06:45 AM

Sounds like you have some restriction in suction...

LukeXE · 08-31-2006, 09:52 AM

What thermometer :p

Duniek · 08-31-2006, 03:12 PM

[quote]is it r402a or r402b ?[/qoute]
gas is new it's r402a
my friend is charging a big cooling system and he charged ~6-7kg r402a temps about -40*C @ 0,5 bar
I have bought rest of bottle from him (~5kg)

Quote:

What thermometer :p

thermo is cheap and very bad but on r290+r600 he shows -42*C

Quote:

If it wasn't the first gas you ever put in the system, meaning it ran fine with another gas - then it sounds like someone sold you bad 402 - maybe a mixed recovery or air in it.

How about vacuum? triple evac? Bad vacuuming would do the same thing

vaccum is good

If possible that stratifying of refrigerant has followed (has stepped) ?

kayl · 08-31-2006, 05:53 PM

dont think its your thermometer.
maybe change the drier and charge the system the way it is with r290.
then if that works fine try r402 again (with a new drier)

the other thing is check that your thermometer probe is attach well and not slipping out. sometimes i use 2 probes just incase i dont have good contact on one

Duniek · 09-10-2006, 12:08 PM

today I make a little test, I use simply cut off hand valve

liquid r402a

I charge system with a new dryer, and vacuming time it's ~4 hours
evap temp is about -30

hmmm maybe one of refrigerant in this (r125??) not condensing :/

Overklokk · 09-10-2006, 12:37 PM

I hade the same problem the first time i used r402a ...... I did all like i did with r507 but godt realy bad temp.The temp was dropping realy slow and my highside pressure was 16-20 bar

Talked too Johan and Jinu and they said bad vacum .....

I tryed again with another vacumpump and voila..... things act like a dream

LittleDevil · 09-10-2006, 12:39 PM

Mybe you have blocked captube, try to change it...?

tnx

Duniek · 09-10-2006, 12:41 PM

thx for quick reply, on next week maybe I have realy good vacum pump
regards

Quasi · 09-10-2006, 04:54 PM

I suppose you are charging with can upside down - for liquid charging right?

Fractionation from gas only charge would still probably not yield temps so far off from pressure readings but I thought I'd ask.

LukeXE · 10-10-2006, 08:47 AM

I tested today that "R402a" in unit for Martian Invader...

-41*C@0bar, the best I can get :| This gas I think is fake...

~~Marvin_The_Martian~~ · 10-10-2006, 08:58 AM

Quote:

Originally Posted by LukeXE

I tested today that "R402a" in unit for Martian Invader...

-41*C@0bar, the best I can get :| This gas I think is fake...

Always nice to hear about unit being worked on

gas bottle.... bad temps,

Luke go get me better one's

n00b 0f l337 · 10-10-2006, 09:23 AM

That sounds like propane or r22. (BTW there is r22 in r402a, are you liquid charging?)

LukeXE · 10-10-2006, 09:25 AM

Yes, I`m liquid charging.

don`t think so that it`s propane, don`t smells like propane ;p

I think it`s R22, or maybe bad mix with too much R22 ?

wdrzal · 10-10-2006, 10:53 PM

402A is -46c @ 0 bar.........-37c @ .56 bar.

johann · 10-11-2006, 12:56 AM

Walt, I am not sure this is correct. As far as I know its -49.2c at 0 bar

Moc · 10-11-2006, 06:10 AM

I got my 12kg R402A today, hope I don't get problems...

Moc · 11-13-2006, 10:38 AM

Quote:

Originally Posted by Duniek

hi
Sometime ago I bought a 5 kg of R402a refrigerant
I charged SS and I have a -35*C on evap at suction pressure 0 bar
and discharge pressure at 15 bar ?
WTF ?

Ohh man.... I have exact the same problem. I build a single stage with a Danfoss SC21CL, two 120mm condensors in serial, about 2,1m 0,7mm captube, brand new bottle of R402A, cold_ice evap.
Temp: around -39°C with 0bar low side und 15bar high side.

I pressure tested it with 12bar Argon, no leak. Also I brazed the Evap and purged it with propane...

So I think I have to buy a new vacuum pump?
The one I uses in the moment is not build for refrigeration.

Duniek · 11-14-2006, 11:16 AM

Quote:

Originally Posted by Moc

Ohh man.... I have exact the same problem. I build a single stage with a Danfoss SC21CL, two 120mm condensors in serial, about 2,1m 0,7mm captube, brand new bottle of R402A, cold_ice evap.
Temp: around -39°C with 0bar low side und 15bar high side.

I pressure tested it with 12bar Argon, no leak. Also I brazed the Evap and purged it with propane...

So I think I have to buy a new vacuum pump?
The one I uses in the moment is not build for refrigeration.

I don't have vacuum pump, I have simply compressor with shreder valve on suction line

On 404a my units is working very well

Moc · 11-14-2006, 11:39 AM

Andl64 my friend sends me his Refco RL-2 for a week ! I will try if I can get better results with better vacuum....

kayl · 11-15-2006, 04:35 AM

Quote:

Originally Posted by Duniek

today I make a little test, I use simply cut off hand valve

liquid r402a

I charge system with a new dryer, and vacuming time it's ~4 hours
evap temp is about -30

hmmm maybe one of refrigerant in this (r125??) not condensing :/

good test to show that r402a does infact boil at -49c.

i found with r410a i had similar problem, like it isnt condensing properly.
I remove a fair amount of r410a and put some r290 in there so on pull down you have higher low side pressure never going into vacum until gets real cold and suddenly the r410a is condensing alot better and the refrigerant matches the pressure charts.