steam drillers, page-4

The hot water in the primary circuit will never be steam. The heat will be transferred from the water through a heat exchanger to a secondary circuit (based on ammonia-water) and should exit the heat exchanger, still as water, at around 50 C. Of course the primary circuit will remain at reservoir pressure up till reinjection, when pressure will need to be boosted. The only cooling that may be required would be on the secondary circuit.

Neil