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View Full Version : Can i use R404a in a R290 system?







fenair
22-06-2013, 10:04 AM
Hi Folks

Quick question, i have a R290 freezer thats under performing and i need to weigh out the contents to ascertain weather it is low charge / possible leakage that is causing poor performance.

I however do not have any R290 to refill with but do have R404a,

can i use 404 in this 290 system or not?

Many thanks for your help

Pat..

1mikeefc1
22-06-2013, 11:46 AM
I don't think you can interchange between 404a and r290, what are the symptoms of the freezer and what are you working on? Chest freezer/static shelf etc...

monkey spanners
22-06-2013, 12:21 PM
Oil be wrong! R22 would be nearer but why not get a can of R290, they sell it in 500g bottles.

fenair
22-06-2013, 12:26 PM
Thanks for the reply, its a foster eco pro 600 top mount cab first generation (2010/11) pull down is poor, and is effected by rising ambient temp, item is outside in a out building and the owner (friend) has a extractor fan running to remove excess warmth from the outhouse, takes around six hours to get back to -20 during the day it apparently struggles to achieve -13.
i suspect low charge, as the condenser etc is spotless, fan is working at a correct speed, internal has no air flow restrictions.
I have check the parameters on the lae controller and all are as per foster recommendations.

However without the appropriate gas to re-charge to correct quantity it is difficult to rule out the refrigerant as the culprit.

internal temp has been crossed with a freezer thermometer which reports the same as the display.

In the absence of R600 hence the question of ok to fill with 404a, which would in theory prove out the charge question.

fenair
22-06-2013, 12:29 PM
Oil be wrong! R22 would be nearer but why not get a can of R290, they sell it in 500g bottles.
Cheers for that this is what i suspected would be the issue, were do you get the cans from, i have checked masterpart and they don't have any just R600.

Pat..

joe-ice
22-06-2013, 12:37 PM
Assuming its a capilliary system ,i couldnt see it working as monkey said oil would be wrong type and condenser would struggle with higher pressures of 404,Generally capilliaries are sized for specific gas type and dont work well with anything else

monkey spanners
22-06-2013, 01:17 PM
Cheers for that this is what i suspected would be the issue, were do you get the cans from, i have checked masterpart and they don't have any just R600.

Pat..

Climate Center sell it, i expect FSW and HRP and Dean and Wood do also. You should have gone on a safe handling course to buy it but many counter staff don't know so.... Just don't set yourself alight!

Copperteck
22-06-2013, 01:39 PM
I've seen people use 134a before and although it may not be correct, the systems have worked. ..... Now ill get my coat>>>>>>>

fenair
22-06-2013, 03:00 PM
Climate Center sell it, i expect FSW and HRP and Dean and Wood do also. You should have gone on a safe handling course to buy it but many counter staff don't know so.... Just don't set yourself alight!
thanks for the help, will try d&w as i have an account with them, i have done the relevant training, i just concentrate on the transport side of things, and not bother with commercial / domestic much, hence no gas, just did not want to buy a cylinder for 150 grams of gas, so hopefully they have the cans.. cheers
pat..

Tayters
22-06-2013, 11:35 PM
I've seen people use 134a before and although it may not be correct, the systems have worked. ..... Now ill get my coat>>>>>>>

I'll join you!
Fitted an R134a compressor in place of a seized R600a one to get a chest freezer going in the local kebab shop. Worked alright but the free cheese burger wasn't much to shout about.

pwned
03-11-2013, 07:37 PM
Propane damages chloroprene rubber.
HFCs swell nitrile that propane is resistant to.

przemo2
17-11-2013, 12:53 AM
i think that is correct 134 will be better in this case .