Comparator

[Henry1]

Hi, how do you determin type and state of refrigerant in an unmarked bottle? Looking at a comparator just as an example if you had 2b guage press, following the line up do you corespond liq temp to pressures showing on guage for diff refrigerants!! ie if bottle was 407c 2b is -18 on comparator, would it be -18 on guage line for 407c?...This made so much sense in my head:rolleyes:

[sedgy]

hi henry,
first of all you have to have some liquid in the bottle< even only a drip< other wise you would only have the amount of vapour pressure that was present.
now for an eg, if you had a bottle marked R22 and the psig was below 58 psig this would mean that there was no liquid in this bottle
on your comparitor 58psig should line up with 0c on the R22 scale.
so we find a bottle of GAS we can feel the liquid slopping about in the bottom of the bottle we take a temp reading, below the liquid line say 25c the psig should be137
on R410A @25c bottle temp should be 220psig.
hope this clears the matter up.
of corse this is virgin gas , if its been re-claimed , it could have air in it.
take it easy , sedgy

[Henry1]

Hi sedgy, anyone else out there, thanks for your reply, still a bit hazy on this matter, this a part of the F-Gas exam, this is the actual question,[ Identifying TYPE and STATE of refrigerant in cylinder prior to charging using a comparator]..I think its a given that it's 407c so we have a liquid we know, they just want to observe me going through the motions, but HOW!!!:rolleyes:...I know i should know this, but came out of college straight into building managment, so have not had much need to use all skills learnt, brushing up on all my old folders hoping to kick brain into gear.

[taz24]

Hi sedgy, anyone else out there, thanks for your reply, still a bit hazy on this matter, this a part of the F-Gas exam, this is the actual question,[ Identifying TYPE and STATE of refrigerant in cylinder prior to charging using a comparator]..I think its a given that it's 407c so we have a liquid we know, they just want to observe me going through the motions, but HOW!!!:rolleyes:...I know i should know this, but came out of college straight into building managment, so have not had much need to use all skills learnt, brushing up on all my old folders hoping to kick brain into gear.


The gauge shows you the pressure and the saturated temp of the refrigerant.

You measure the pressure and then the temperature of the bottle and then look
on the compariter to see which refrigerant is at that pressure for that temp.

So R22 at 20 degC should be at 9.2 bar (135psi) if it reads a different pressure it
is not R22 or it is contaminated.

The trouble with pressure temp relationships of refrigerants is that a lot of new
refrigerants share common opperating pressures and temps so tell some
refrigerants apart is hard.

taz

.

[NoNickName]

What an idiotic question. Anything can be in the cylinder: the pressure to temperature relationship is not unique to a single substance in the world.
How would you realise whether CO2 or N2O is in a cylinder? They have the same scale over the comparator.

[Henry1]

Thank's Taz, that explains it nicely, all becomes clear, NoNickName, yes there probably are a lot of idiotic questions posted but that is what forums like this are for, to HELP, re-read my original post, i am talking about specific refrigerants..

[NoNickName]

No, the OP is perfectly licit, it is the f-gas examination which shall not include such a question.

[Henry1]

O.k mate, my bad..:off topic: