View Full Version : Topping up R22

23-05-2016, 12:40 PM
Is it ok to top up a R22 system with R422D

23-05-2016, 03:19 PM
Whilst R4422D has been created to operate in place of R22 and some sources suggest that it may well work as a top-up, my thoughts would be that, it is not be best practice to add R4422D as a top-up.
If the R22 system has a measured quantity of refrigerant, you probably have had to remove the gas to carry out a repair. You are not then allowed to add the recovered refrigerant back into the system.
If however you have found and repaired the leak without taking the refrigerant out, then how have you high pressure leak tested the system to ensure that there are no further leaks.
Presumably if you really had to, under this scenario, then possibly you could add the gas and charge it by observing the sight glass, if one was fitted.
The cooling capacity of the system may well be adversely affected by the mixture.
Best answer would be to reclaim the R22 for destruction and start with a known quality and quantity of R422D.

23-05-2016, 04:33 PM
The F-Gas directive is fairly clear, you may not under take any work on an R22 system unless it is to recover the charge for destruction. Putting gauges on to check pressures etc AFAIK is not acceptable.

monkey spanners
23-05-2016, 06:07 PM
What Al said^ Basically the only time you are allowed to fit your gauges to an R22 system is to decommission it. No component replacements etc are allowed, basically they can run the system until it breaks then its convert to new refrigerant or replace the system time.