Yup, sounds good, as with many domestic heating systems the pump isn't really a pump, more of an impeller which enables dead heading without issue. Pressure within the system is achieved by heat (expansion) only, not by impeller which remains constant i.e no clutch.

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David


1996 Mercedes S124 E300TD - 129k - rolling restoration project -

1998 Mercedes W210 300TD - 118k (assimilated into above vehicle)