convert to R290

I'm having a whole bunch of freezer systems moved from old freezers to new

they almost all run on R404a


talked to engineer about swapping to a different gas now, the thinking being r404 will be harder and harder to work with in the future

we pondered about r290.... condensing units are all outside in fresh air, short pipe runs to evaps, would need to swap to explosion proof lights inside the freezers and add alarms

but... there doesn't seam to be a lot of that going on?

reluctant to switch to another gas now that will be phased out later on


if we swapped a few systems over now, could recover the 404 and save it for the other systems later on


can't see a lot of info about r290 in older scroll compressors?

anyone have any ideas/input?

you need to check if compressors are suitable to run on R290 you will need spark proof electrics also volume of room needs to be calculated to check maximum charge of refrigerant that you can have in the system. there are other refrigerants you can convert to that might be easer

I'm wondering which other gas I can retrofit which will give a decent capacity and be around for a long time?

r290 is the only one I can think of?.... have to assume there'll be a steady purge (hehe) of refrigerants


spark proof electrics are no problem, have some experience with that stuff


didn't think about volume of the room, that might be a problem, rough 1700cubic feet (about 50 cubic meters) and 3 seperate systems with a bit over 10kg of gas in each


well... they had ~10kg of r404 in them, I think charge is noticeably lower with r290 ?

Units outside cooling brine, and pump the brine to the rooms?

Units outside cooling CO2, and pump liquid CO2 to the rooms?

Sell the old kit and use the money to buy units or a chiller that runs on a natural refrigerant?

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You might want to look at.

Page 7 has your limits.

https://www.logic4training.co.uk/wp-...Guidelines.pdf

It's from ACRIB.

Regards

Rob

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