View Full Version : Replacing a 410a compressor with a 407C compressor

31-12-2014, 05:40 PM
Hi Guy's I am new to this and was wondering if you experts could advise.

I have an Air to Water system that the compressor seems to have blown its run windings.
I have replaced the capacitor which cured the problem for about a week, but now the motor once again will not start, I have tested the new capacitor and it is still OK.
This system is filled with 410A refrigerant.

Now I have an Air to Air system of about the same rating (about 7 KW heating) that I don't need, but it has 407C refrigerant.

Now my question, is it permisable to use the compressor to replace my faulty one, if so which would be the best refrigerant to refill with, 410a as per the original or 407C to match the replacement compressor.

I must stress I am not contemplating doing the task myself but will need the services of an AC engineer, but if it is not possible to do then I will have to look for a 410a replacement before proceeding further.

Regards John

monkey spanners
31-12-2014, 08:28 PM
Its not practicable, the two refrigerants have different pressures for the same working conditions, and so the two compressors will have different motors and displacements to suit the respective refrigerants, even though the overall system duties are similar.

31-12-2014, 10:29 PM
Thanks for your reply Monkey.
I understand they have different refrigerants/pressures which is why I thought that maybe if I used the 407c Compressor with 407c Refrigerant and at the 407c pressure in what was the 410a system, it would work.
I am assuming that most of the other components in the system don't care much which refrigerant is flowing through them and am I right in thinking that the 407c runs at a lower pressure.
Regards John

01-01-2015, 12:32 AM
The expansion devices will be selected for 410A.

01-01-2015, 12:37 PM
Why try to reverse the optimised technology, when the best and cheapest approach would be to have the R410A compressor replaced with the latest available equivalent item.
The pressure and temperature sensors would have been selected for optimum performance using R410A and the corresponding electronics would have been designed around those data inputs.

02-01-2015, 12:20 AM
Thanks for the input guy's, I thought I might be able to save the cost of the compressor and use something that is just taking up room, but obviously not.
Back to plan B I guess.

Thanks again and a Happy New Year to all.