PDA

View Full Version : Condenser Replacement



tonyk
19-12-2012, 11:11 PM
Hi, I have an old carrier r22 dustbin type unit rated at 12kw serving a dx coil mounted in a supply air duct and control is by a solenoid valve on the suction line that causes the condenser to pump down and go off on lp when temperature is achieved.
I want to replace the condenser unit with a 407c unit to keep existing pipe and coil, do I just need to get a 12kw condenser unit and can the expansion valve be sized to this?
Any help would be greatly appreciated thanks.

moideen
20-12-2012, 04:58 AM
Hi, I have an old carrier r22 dustbin type unit rated at 12kw serving a dx coil mounted in a supply air duct and control is by a solenoid valve on the suction line that causes the condenser to pump down and go off on lp when temperature is achieved.
I want to replace the condenser unit with a 407c unit to keep existing pipe and coil, do I just need to get a 12kw condenser unit and can the expansion valve be sized to this?
Any help would be greatly appreciated thanks.
you can use the same expansion valve.it has very similar properties to r22.you should flush out the circuit and charge POE oil.
moideen-dubai

chemi-cool
20-12-2012, 03:52 PM
407f will be a better choice, the new condensing unit should be the same size, When you state that you want condensing unit for 407c or f, it will come with POE oil, Place the SV on the liquid line before the TXV, clean the pipes with any certified cleaning agent to remove mineral oil left overs.

Check the SV for leaks after you run the new system, oil changing can affect the rubber seal.

Fri3Oil System
21-12-2012, 07:52 AM
407f will be a better choice, the new condensing unit should be the same size, When you state that you want condensing unit for 407c or f, it will come with POE oil, Place the SV on the liquid line before the TXV, clean the pipes with any certified cleaning agent to remove mineral oil left overs.

Check the SV for leaks after you run the new system, oil changing can affect the rubber seal.

The best agent for removing the existing MO is R22, used in a closed circuit. When you properly clean the whole rest of the installation, evaporators i.e., you will achieve also a better performance.
Agree with Chemi Cool, the mixture of POE+HFC will attack the seals elastomerers and create leakages, so it would advisable to switch the seals to neoprene ones.
Read case study of a R22 conversion to R407C here: www.fri3oilsystem.com/retroficase.zip (http://www.fri3oilsystem.com/retroficase.zip)

Regards,

Nando.

tonyk
23-12-2012, 09:25 AM
Thanks guys advice taken and understood.

install monkey
29-12-2012, 09:38 AM
all aluminium coil on a carrier dustbin- scrap yards love em!:D