Originally Posted by
TSK
I have seen this free cooling system in place but not worked on it, refrigerant vapour from the evaporator (+10C water chiller) is allowed to by-pass the compressor using a valve, the vapour travels up to the condenser on the roof and condenses into liquid, the liquid being heaver than gas and affected by gravity stacks up in the liquid line and creates a PD across the expansion valve, saw it for myself, cooling the water by a few degrees but that was all, not sure the result was worth the effort but maybe in the right conditions, V-cold outside by the condenser?