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KegSalad
10-09-2016, 01:21 AM
Hi guys, I'm a new member so please be easy on me.

I'm new to the industry and looking for some information.

I have a blast freezer bitzer compressor to change out, I'm thinking all I need to do is shut the service valves and recover the vapour inside. Now all i have worked on is recovering R404a in a liquid state, no problem. But now I'm recovering in a vapour state, do I turn the recovery machine on vapour setting and connect my hoses to the liquid valve still on the recovery bottle? (Or vapour) as I'm guessing I want the refrigerant to go into the bottle in a liquid state?

Sorry if this is a stupid question, but I would really like to know the correct method

Thanks in advance

Rob White
10-09-2016, 01:29 AM
.

It does'nt matter too much which valve you put it into the cylinder.
I alway put it in through the liquid port because I always draw liquid
out and it saves messing round with the bottle adapters and such.

As for your machine if it has both a liquid and a vapour setting, then yes
pull it out in the vapour and push it into the cylinder through any port,
like I said I always use the liquid side of the cylinder anyway.

Regards

Rob

.

KegSalad
10-09-2016, 01:53 AM
Hi Rob,

Appreciate the quick reply and info.

One more question, does the recovery unit act as a condenser to change it from a vapour state to a liquid state?

Cheers

Jayce
10-09-2016, 03:43 AM
Hi everyone,
I m sorry i can not find own to create my own post... (it s the first time I use a forum in my all life...)

anyway,

I want to buy an ice cream machine to do some street ice cream but apparently the gas is R404A and I will use the machine outside with a temperature around 50degres... I saw than it could be dangerous to use the R404A in that temperature condition... and I don t want to risk to have any trouble or play with a potential bomb......

could you please let me know what could be the gas able to hit -40/-45 degrees and able to run with a environmental temperature around 50 degrees?

thx in advance for your understanding.

Rob White
10-09-2016, 04:19 PM
Hi Rob,

Appreciate the quick reply and info.

One more question, does the recovery unit act as a condenser to change it from a vapour state to a liquid state?

Cheers


Most recovery machines have a condenser on them and
they try their best to turn the recovered refrigerant into
a liquid.

Rob

.

The Viking
10-09-2016, 05:05 PM
One more question, does the recovery unit act as a condenser to change it from a vapour state to a liquid state?
Cheers
Another trick, if you are recovering any vast amounts of vapour, is to cool the recovery cylinder whilst you are reclaiming. Normally we do this by having a trickle of water on to the cylinder ensuring it is wet and acting as an evaporative cooler, otherwise as you push the hot vapour/liquid in to the cylinder it will get warm and this will slow down your recovery progress.

:cool:

KegSalad
10-09-2016, 05:16 PM
Nice one, thanks for the information guys you've cleared that up for me!

You learn something new everyday :cool:

Cheers

monkey spanners
10-09-2016, 06:43 PM
If you are just seeking to empty the compressor of refrigerant to enable replacement, recover the refrigerant into the receiver, no need for a recovery cylinder then.

KegSalad
10-09-2016, 07:37 PM
Also got to change out the single PRV's on the water cooled condenser to duel PRV's. It's has a standby unit with a common receiver so need to keep the other system running while changing this out.

When going to charge back into the system, do you use the recovery unit to pump the liquid back in once the pressure has equalised from the recovery cylinder?

monkey spanners
10-09-2016, 11:01 PM
Yeah, pump it back in with the reco machine.

cadwaladr
11-09-2016, 02:00 AM
Why not just use a well vacced out recovery cylinder,shut off the service valves and let the vapour transfer to the cylinder?

KegSalad
11-09-2016, 10:23 AM
I thought R400 series refrigerant had to be recovered/charged in liquid form?

nike123
11-09-2016, 10:53 AM
I thought R400 series refrigerant had to be recovered/charged in liquid form?

Charged as liquid and recovered in any state, as long as you ensuring that all recovered refrigerant will be returned to system.
Reason is fractionation. If you recover and recharge all refrigerant then there is no fractionation no matter of liquid or gas state of refrigerant.

KegSalad
11-09-2016, 02:56 PM
Thanks for that, I understand now how recovery and charging works now.

It's much appreciated all your help

Cheers guys :cool:

el_donks
16-09-2016, 08:09 AM
Why not just use a well vacced out recovery cylinder,shut off the service valves and let the vapour transfer to the cylinder?

Wouldn't you need the recovery machine anyway to finish recovering all the gas? It would be a good start tho.

BradC
20-09-2016, 11:23 AM
Wouldn't you need the recovery machine anyway to finish recovering all the gas? It would be a good start tho.

You *could* pack the recovery cylinder in a cooler full of dry ice and methylated spirit. No reco machine needed :)

Yes it's a dirty hack, but great for recovering from nasty burnout a without putting that grunge through your reco machine.

el_donks
21-09-2016, 08:59 AM
Sure, problem comes with big setups/large gas quantity :D