In article ,
ARW writes:
Just had a call from a neighbour with no HW or CH.

Potterton HE plus boiler.

Took me 30 seconds to decide to hit the pump in the airing cupboard with
a hammer.

Job done

My shower pump is currently in need of exactly that before each shower.
The little flow detection magnet in the hot pipe gets stuck in the no
flow position. This doesn't stop the pump coming on because the one in
the cold water side moves and triggers the reed switch, but the hot
side one blocks the hot flow until dislodged by a thump.

I took it to bits, but it's impossible to get to the bit where the
magnets are to clean it (solvent welded parts). Descalers and other
liquid cleaners had no effect.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]