R12 refrigerant for centrifuge

Science Committee has a large centrifuge that gets very hot as it spins, it has a coolant system that uses R12. It has low coolant and needs to be re-charged.

Would anyone in the community have some extra R12 coolant and be willing to donate about a lbs to Science for its centrifuge?

You might also check for leaks. Also, I believe R12 requires licensing to buy.

It does, but we have a couple of AC techs at DMS that have that license if we know the system just won’t leak it back out again.

I think @TBJK might have some advice on this.

2 Likes

I will check for leaks before hand. The current price for R-12 is about 31$ a lb. minimum of 30 lbs. I can buy it, however that’s some scratch for needing at the most 1lb 12 ounces.

2 Likes

Best case I was telling Josh was someone has many 12 ounce cans of R12 that was used for old car ac’s

2 Likes

I wonder if is a standard refrigeration unit that can be converted.

1 Like

The most standard is R-134a. However you have to change the oil as well as you loose capacity. IIRC about 30%.

There are others.

I thought propane was a suitable alternative for R-12?

I’ve got 2 12oz cans, Dupont branded r12

2 Likes

Depends on the environment. Propane is flammable and R12 isn’t.

Propane is higher pressure. It’s more of a replacement for R22. I haven’t compared the enthalpy charts on them yet.

1 Like

Ahhh, my bad. I was thinking of R22.

Not that I have any experience doing it, but can’t you also replace R-12 with R-134a? Gotta drain the mineral oil and replace it with PAG.

Time to go use some air duster cans which contain … surprise! … R-134a. :slight_smile:

I leak checked the machine this morning. I did not find any leaks which means the leak is not significant enough to worry about. I will be filling it sooner than later.

3 Likes

which machine?

The refrigerated centrifuge

wonderful thank you, how did you leak check it?

1 Like

I used my Inficon D-tek leak detector. Specs are .10 Oz a year leak rate detection for minimum.

3 Likes

Just a quick question. Is it better to test before or after filling or both or doesn’t matter?

Before. If you had leaks, you would want them fixed before adding any more refrigerant