View Full Version : How to charge R744 without charging machine

16-01-2013, 09:09 AM
Can anyone help me out the charging procedures of R744 in the Workshop without any charging Machine. We are doing this project for the first time and the company dont want to invest on Charging Machines.

So, can any one help me out in this regard . please let me know on safety point of view as well as system point of View.

Evaporating - -10 Deg C

Condensing - 50 Deg C

Compressor capacity - 1/3 Hp

Refrigerant - R744

Appreciate your time and support.

Thanking you

Best Regards

16-01-2013, 06:51 PM
You won't be condensing at 50C.... operation in that range will make it a transcritical system.


It sounds like the company needs to invest in some design before anything else.

11-05-2013, 02:37 AM
Can i suggest looking into either a trans critical design in order to get the required condensing temperature or alternatively a sub critical cascade system.

R744 present a lot more design restrictions in comparison to HFC or alike refrigerants and as a result the system needs really to be designed by a specialist. There are several resons for this for example component selection will be different, material criteria uprated to cope with the higher pressure ratings,etc.

You need to design a system in such a way that the liquid refrigerant cannot be trapped due to the rapid expansion and pressure increase that will be exerted by the refrigerant

Also note operating procedures vary with using R744 and should not be attempted by anyone who is not trained or deemed competent. R744 has far more extreme rates or reaction than convetional refrigerants! therfore must be handled with care.

feel free to message me if you require more help

Best regards


26-06-2013, 10:39 PM
Hi If you wont to charge the coulding system without charging machine you can connect the the refrigerant R744 in the high pressure valve open the valve from the mensura to make possible the refrigeration to pas to the condensator if you could with the water the condensator from the outside the amount of the refrigerator will pass very fast from mensura to condensator