Refrigerant charge

[nui]

Hello, Is there any way of finding the charge/volume of a system?, say there's been a leak, it's been fixed, and now you want to top it up.

Cheers,

[The MG Pony]

try and find an Info plate, if no info plate then ya got me, I have the same problem with a twist lol.

[NoNickName]

Top up until reaching spec subcooling.

[afeef]

no.....
untill you get 3-5 c super heating
afeef

[NoNickName]

Superheating can be varied depending on the TXV adjustment. Refrigerant charge must be checked against subcooling, not superheating.

[afeef]

but the most important term is the superheating ,
the effecincy of system is depend upon it , the life of compressor depending upon it also
thanks no neck name

[Renato RR]

How many kW on which evaporation temperature?And type of machine also?Which refrigerant you use?

Renato

[NoNickName]

but the most important term is the superheating ,
the effecincy of system is depend upon it , the life of compressor depending upon it also
thanks no neck name

Of course.

[27143721]

1. check the compressor current of a good equipment ( the same working conditions)
2. take it as reference and charge the problem equipment.

[Peter_1]

This was already on this forum but charging by current is completely wrong.
I should say, first subcooling and cross-check also superheat.
But you can't predict this on forehand.

[chillin out]

Keep adding gas untill the sight glass fills up (or your bottle runs out..lol)

If your comp gets covered in ice then start to runnnnnn.

Chillin

[The MG Pony]

My vote is on sight glass, I winged it and did just that on my totally pieced together from archaic parts system and bang, hit -34 under load using R-290 and a 1/2ton R-12 TXV under load, and interestingly enough didn't take much extra gas to get it full

[afeef]

My vote is on sight glass, I winged it and did just that on my totally pieced together from archaic parts system and bang, hit -34 under load using R-290 and a 1/2ton R-12 TXV under load, and interestingly enough didn't take much extra gas to get it full

sight glass give you the approximate amount of charge, it can help you monitoring your a/c system from leackage
but not to determine the exact refrigerent needed .
afeef

[The MG Pony]

Ya I know that, but for a good fast fix it does the job marvellously

[abdulazman]

Hi Nui

If in doubt than go back to basic.Check on the spec or info on the nameplate of the unit like a few of our members recommended. Reclaimed the refrigerant performing liquid transfer, weigh the charge and add the necessary amount short.

Good luck mate.

[star882]

My vote is on sight glass, I winged it and did just that on my totally pieced together from archaic parts system and bang, hit -34 under load using R-290 and a 1/2ton R-12 TXV under load, and interestingly enough didn't take much extra gas to get it full

1/2 ton unit using R290???

[The MG Pony]

Why not?, in reality the whole thing is a real hack job of a unit that I build whilst I am building the "real" system.

"The real" System I'm making will be using R-134a, I may use a mix or R-134a and R-600 to improve its efficiency.

[Brian]

You could be very technical about the situation and work out the total volume of the different phases!

:0