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View Full Version : Chiller to heat pump



dannycool
20-03-2008, 06:15 PM
I was wondering if anybody could tell me if its possible, and what would be involved in modifying an existing air cooled packaged chiller so that it could heat water utilising the existing chilled water pipework and fan coils, but still able to changeover to cooling in the summer. I am not am design engineer so i cant provide you with any calculations etc, but would just like to know if and how its possible.

thanks in advance
Danny

The MG Pony
20-03-2008, 07:00 PM
Providing you have a good knowledge of the system then techicaly yes it is, you'd have to check to ensure your coil is of the right design for it, if it is add a reversing valve and add the needed electronics to drive it. Depending on the metering device you may need to add check valves or do some redasigning, add a bidirectional filter drier.

in short it can be don, but there is a good deal of work that must be don to do so.

nike123
20-03-2008, 07:23 PM
Providing you have a good knowledge of the system then techicaly yes it is, you'd have to check to ensure your coil is of the right design for it, if it is add a reversing valve and add the needed electronics to drive it. Depending on the metering device you may need to add check valves or do some redasigning, add a bidirectional filter drier.

in short it can be don, but there is a good deal of work that must be don to do so.


I pretty much doubt that present evaporator could be used as condenser in heat pump mode if one simply add 4-way valve and nedded electronics and other parts.

The MG Pony
20-03-2008, 08:19 PM
I pretty much doubt that present evaporator could be used as condenser in heat pump mode if one simply add 4-way valve and nedded electronics and other parts.

Hmmm true, depends largely on what type of heat exchanger he has. I do think I mentioned he'd have to check that though.

I have converted Window A/Cs to heat pumps with good success, I rewire it so in heating mode the fan will be locked into full speed and usualy keeps head pressures resonable. but it is mostly manual control, hence why I mentioned he only should try if he has deep understanding of it.

frank
20-03-2008, 08:20 PM
In addition to a reversing valve you would need to consider adding a suction accumulator to prevent flood back, defrost controls, outdoor TEV, non return valves across each TEV and fan speed controllers. Simple init? :D

nike123
20-03-2008, 08:23 PM
Hmmm true, depends largely on what type of heat exchanger he has. I do think I mentioned he'd have to check that though.



I just wanted to emphasize that.

nike123
20-03-2008, 08:27 PM
In addition to a reversing valve you would need to consider adding a suction accumulator to prevent flood back, :D
And appropriate liquid receiver.;)