Heat pump for domestic hot water - has IC engine driven compressor, with heat exchanger extracting exhaust heat

摘要

The operating fluid is circulated through an evaporator, to take heat from the atmosphere and through a condenser to transfer heat to the heating medium, by a compressor driven by a combustion engine, e.g. diesel. Warmth is also produced by intermittent operation of the engine for a period controlled by a pressostat. Parallel with the compressor is a by-pass and the line between condenser and evaporator contains a valve (3) which is closed before the engine is stopped. For starting the valve is briefly opened until the pressostat emits an impulse to switch on the engine. During starting the open by-pass is kept free of pressure until the engine has reached the speed and torque suitable for running the engine, whereupon the valve is opened, either by a timing device or a revolution counter.