R22 Vs R417a

[spclim]

Dear members,
I'm new to this, and I've a small question that I faces on my daily work..
I know that R417a substitutes R22 with some loss of performance of course at about 5-10% , but my question is: on an equipment running with R22, can I just add R417a ontop of the existing R22 (leakage problem), OR should I need to empty the equipment first and fill it with R417a completely?
please advise!!
Urgent

[FaultCode]

You need to empty R22 and replace with R417a.

[spclim]

Thank you for your answer, I wish it was just adding over, what a huge work to do. (to empty 190 Split system units)...

[FaultCode]

Manufacturers guidelines for retrofit here...

http://bit.ly/2sfiqzp

[hookster]

Thank you for your answer, I wish it was just adding over, what a huge work to do. (to empty 190 Split system units)...

If all the split systems are R22 then they are a very old model of equipment. As you just want to add a drop in refrigerant, I feel you are going down the wrong route here!

You should rather be speaking to your client about a replacement program for the superceded equipment. Leave the equipment running and build a budget replacement program over the next 5 years for example with replacing units with new. also have a failure budget what increases with each year depending on failure rates.

Putting a new refrigerant in old equipment is false economy, working R22 systems can be left operational. Trying to retrofit refrigerant on old systems will increase their failure rate. I would hazard a guess that a lot of the electronics and hardware components will have been superceded and no longer easily available.

My advise is to approach a single manufacturer and in conjuction with the client approval agree a replacement program for their equipment and the manufacturer will be more than happy to offer good price support if not find another manufacturer.

[spclim]

Thank you so much for your suggestions, I'll try to convince my client to do that...