Two stage central heating pump - has two sections on common drive shaft which may be switched in series or parallel

摘要

The two stage circulating pump for a central heating system, has the two stages, (A, B) mounted on a common drive shaft (3) at the output of a single motor (4) each stage having a rotor which is about 55 mm. diameter. It can be used in a circuit with a vain heater and a booster heater as well as a hot water tank, with a thermostatically controlled switching arrangement so that the two stages of the pump can be operated to feed only one heater, or in series to feed both heaters, or in parallel.