Identify R12 or R134a

[Chris Ellison]

Is there an easy way to differentiate R12 from R134a in a system WITHOUT a dedicated gas analyser? Thanks in advance for any ideas.:D

[multisync]

Use a halide leak tester

http://www.uniweld.com/catalog/refrig_hvac/leak_detector/leak_detector_access.htm


Multisync
London

[chillin out]

It's smell.

Also you could use a slide rule.

Chillin

[Chris Ellison]

It's smell.

Okay, that makes sense if they differ in odour, will have to try that and see how good my nose is.

Also you could use a slide rule.

I will take the bait and ask how to differentiate using a slide rule? Will probably wish I had not asked!!:o

Maybe someone could tell me the difference in flame colour using a Halide tester?

Thanks again.:D

[nike123]

It's smell.

Also you could use a slide rule.

Chillin

Chillin, refrigerants CFC and HCFC are odorless. Only thing that could smell is oil and contaminants diluted in refrigerant.

[nike123]

Turn off questioned unit, force condensation fan to operate, wait some time that suction and discharge pressure is equalized, take reading of air temperature leaving condenser and take reading of pressure at discharge port. Compare that with saturation temperatures of R12 and R134A for that pressure and you will find one what is closely matched. That is your refrigerant in system.

[paul_h]

The halide torch is a good idea, R12 will turn the flame bright green.

[Electrocoolman]

The halide torch is a good idea, R12 will turn the flame bright green.

What does R134a do to the flame? ....not tried it.

[icecube51]

Turn off questioned unit, force condensation fan to operate, wait some time that suction and discharge pressure is equalized, take reading of air temperature leaving condenser and take reading of pressure at discharge port. Compare that with saturation temperatures of R12 and R134A for that pressure and you will find one what is closely matched. That is your refrigerant in system.
sorry here, but i think if you measure the air leaving the condenser when its 20C° out there,your readings will be approx the same, so this wont work.

Ice

[nike123]

You are right, I was speaking generally and not considering similarity in pressures with R12 and R134A.
Sorry, guys! :o

[jose regueiro]

Sorry my english. Take a little cilinder (rechargable) make vacum, and fill up (no more 70 % water wheigt capacity), with unknows refrigerante ( part liquid) then put a diferent temperatures and take pressures and compare

[Grizzly]

What does R134a do to the flame? ....not tried it.

I think Paul and Multisink may have something there.

I a halide torch is NOT affected by R134a. (the flame won't change colour)
Mind you a lot of places get a bit paranoid about the open flame bit!
And check where those fire alarm sensors are.
Better still if relevant Isolate the plant room Alarm
whilst checking.
Grizzly
Just realised you can't buy Halide Torches in U.K. anymore! Or can you?

[Voyager]

a halide torch is NOT affected by R134a. (the flame won't change colour)

r12 & r134a are both fluorocarbon gasses, so they will both turn the flame bright green/blue.


Mind you a lot of places get a bit paranoid about the open flame bit!

The open flame is the least of your worries. The resulting combusted gas is TOXIC.

[multisync]

It's the chlorine which turns the flame green. R134a is Chlorine free is it not?

Multisync
London

[paul_h]

It's the chlorine which turns the flame green. R134a is Chlorine free is it not?

Multisync
LondonCorrect, no chorine in R134a. I always used a halide for leak detection in the 1990's. I had to buy a electronic leak detector because a halide does not detect R134a

[icecube51]

just thinking out Laud here, if you have a digital manifold and could switch from R12 to R134a, can you not see instantly the difference in the superheat ???

Ice

[nike123]

just thinking out Laud here, if you have a digital manifold and could switch from R12 to R134a, can you not see instantly the difference in the superheat ???

Ice


Why superheat?

[richardb14]

r12 & r134a are both fluorocarbon gasses, so they will both turn the flame bright green/blue.



The open flame is the least of your worries. The resulting combusted gas is TOXIC.

and there's me thinking its just chlorine that turns the flame green

[Voyager]

And theres me thinking the C&G training manual would be right :confused:

Clearly it is a bit ambigious (sp?), as the one I have only says halide can be used to test for CFC / HCFC without actually naming the gasses.

I've never used halide anyway, got a sniffer instead.

Oh well, live & learn.

[Grizzly]

And theres me thinking the C&G training manual would be right :confused:

Clearly it is a bit ambigious (sp?), as the one I have only says halide can be used to test for CFC / HCFC without actually naming the gasses.

I've never used halide anyway, got a sniffer instead.

Oh well, live & learn.

Voyager...
Fair Play to you.
Your point stands.
Silly me I happened to leave a R134a cylinder valve just cracked open.
Luckily I just happened to have my trusty Halide Torch fired up!
Guess what!
The flame turns a purple green, it's no-where near as an intensive a colour change as say R22 or R12.
But "never the less" it does change.
So your vindicated Voyager......

So it would be inconclusive to test with a Halide torch.
Any other suggestions anyone?

[QUOTE]The open flame is the least of your worries. The resulting combusted gas is TOXIC.[QUOTE]

So is AMMONIA but just the same treated carefully no harm is done!
And at least when you are told that it is Toxic you tend to treat it with some form of respect.
Grizzly

[Chris Ellison]

Thanks for all the comments guys. I am really surprised that what I thought was a simple question has turned out to be such a problem. I have asked about a dozen refrigeration service people the same question and have not had an answer that stood up to scrutiny. I would be real happy to get a definite answer if anyone has any more ideas.

Off topic, I purchased a small "Signal Air Horn" the other day. One of those little things that sit on a small aerosol can. Guess whats in the can??? Yes, R134a!!!! So much for not venting to the atmosphere. Also found cans of "Compressed Air" for blowing out electronic items, full of the same thing.