Recovering R407c into pump down bottles for reuse

[tradybrad]

Hi All
Need some advice on R407c. I currently have a failed compressor on a system and i need to know Can R407c safely be reused if put into Clean pump down bottles. I have done oil/moisture samples which came back ok and i know to change all driers etc . My Biggest concern would be maintaining the correct integrity of the refrigerant when i remove it from the system. Is there a correct procedure to remove R407c from a system for reuse and ensure correct blend is maintained. System Has 90kgs of R407c so obviously i have to use more then one bottle during pump down procedure thus i dont want any issues to arise when recharging system from 2 bottles.I am also not sure if correct amount of refrigerant was originally in system in knowing this i may have to trim charge and need correct blend to be present in Refrigerant when i recharge system from pump down bottles.A refrigerant integrity test checking blend properties currently in system has been done by a lab and currently correct ratio of blend is correct in system.
Brad.

[Rob White]

.

If you are happy with the refrigerant it does not mater how you
pull it out as long as you pull all of it out and when you put it back
in make sure it all goes back in.

You are right to be concerned with 407 but as long as it is all in the
system when you are finished there will be no problems at all.

The obvious way to remove the refrigerant is in liquid form and if
you have a reclaim pump that pumps liquid then connect to the
liquid side (receiver) and pull the liquid out.

The first cylinder you recover (if pure liquid) will have no refrigerant
separation so when you come to recharge the system just bomb
charge it all back into the receiver.

If you cant get all the refrigerant into the system in one go you will
have to run the system and charge the remainder into the suction,
just make sure you charge it as liquid but throttle your gauges so
pure liquid does not get into your comp.

Regards

Rob

.

[tradybrad]

Rob
Many thanks for the advice.

Brad.

[1mikeefc1]

Have tried this before and ended in having to reclaim and replace as pressure problems all over the show caused by separation of liquid and vapour. Also why has the comp failed? Could end up with burnt gas back in or acid.

[Rob White]

.

If the refrigerant is ok before it is pulled out it will be ok when it is put back in.

Rob

.

[1mikeefc1]

.

If the refrigerant is ok before it is pulled out it will be ok when it is put back in.

Rob

.

true but what is the comp fail cause? Has an acid test been carried out? Was it correctly charged to start? Any one of these and your causing a rod for your own back.

[install monkey]

gas prices in oz, it would be going back in burnt or not!

[Rob White]

true but what is the comp fail cause? Has an acid test been carried out? Was it correctly charged to start? Any one of these and your causing a rod for your own back.

I agree with you when you say it is important to find the cause of the fault,
but in this case the original poster says he has had the oil and the refrigerant
tested and both check out ok. So if the refrigerant is ok it will be alright to reuse.

If tests came back and said acid or fractulisation then yes replace the refrigerant
but not it would seem in this case.

Rob

.

[tradybrad]

Hi guys
like I said in original post oil sample was taken from failed compressor and came back ok for acid/moisture levels and viscosity was ok. Refrigerant sample was done removing liquid refrigerant from receiver and integrity/ composition came back ok.
my biggest concern was removing refrigerant from unit into multiple bottles and maintaining correct composition of refrigerant to make sure I don't have any issues when needing to recharge unit.
original compressor was DTE and I was surprised on findings on oil and refrigerant samples when they came back from lab. I guess something else by sides acid/moisture or lack of motor cooling caused motor to burn out.
i will be changing as per normal contactor and overload plus driers etc.
any other advice would be appreciated.
Brad.

[Scotty89]

Should be fine to reuse. There is always going to be liquid vapor separation. When charging back into the system, charge liquid only but you need to leave a bit of liquid in the bottle as to make sure your charge is liquid only. This way you can avoid ruining the blend.

[PaulZ]

Hi Brad
Fractionation occurs inside the system when it is operating but causes no problem because the blend component percentages overall do not change, if you leak to atmosphere then these percentages can change and this is what causes the problems with high discharge pressures.
If you replace everything you recover you should be ok. I wouldn't leave anything in the reclaim bottles as suggested by Scotty but I would charge back in as a liquid.
If the compressor has burnt out it would be advisable to install a burnout drier in the suction to the compressor as a safeguard. Even though you took a sample of the compressor oil and it was ok a suction drier will ensure protection for the new compressor.
Paul