Dehumdifier refrigerant changing

[so2 critter]

Have a old small dehumidifier which leaks about 2 oz. per year
and cannot find leak. Need a recomndation of what new type
refrigerant I can use (in charge a cans). I am a retired hyvac mech and out of the r-12 it takes. Also, what pressures
would this new refrigerant have. (hi and lo side). I do not
wish to have change to the oil. Just evacuate the system and go.

[ckr74]

Be better off if you purchaced a new one. I think you can still get 134A in small cans but you'll need to change oil.

[condenseddave]

Yeah, you can get a new one pretty reasonably.

134 is the only one that I know of that is available in the 10 oz. cans anymore.

You must have some old buddies still in the business that could hook you up with a shot of MP39 or 409A, don't you? Or did you burn all your bridges like I'm in the process of doing?:D

Where are you in NJ, BTW?

[so2 critter]

I live in Middletown NJ. Just outside of Red Bank.. What
pressures should I expect from 409 a ? Use same oil I hope.?
Bad to use 134a without changing to the new type oil??????

[condenseddave]

http://ww2.imagewiz.net/images/hvac/125314_PT_Chart_2.jpg
http://ww2.imagewiz.net/images/hvac/125313_PT_Chart_1.jpg

409 will run a higher discharge temp than 12.

I wouldn't hesitate to try 134a without an oil change on something that small, but that would be entirely up to you. The manufacturers require a conversion to POE. I've done it in the past, on larger equipment than that, but, again, I can't guarantee it would work...