On 06/03/2020 11:38, Jonathan wrote:
On Thursday, 5 March 2020 08:27:28 UTC, Stephen wrote:
On Tue, 3 Mar 2020 09:58:57 +0000, alan_m
wrote:



Pumps usually seize only if they have been left unused for a
period of time such as in a system where the pump is only used
for central heating


Hello,

Thanks for all the replies.

The pump is only used for CH. I had the CH thermostat turned dwen
low for frost protection, so I don't know how often the boiler
fired up while I was away. I must have fired at least once to blow
the fuse.

I never thought to power the pump independently, thyatnks for
that, I'll try that if there is ever a next time.

What limited me on the day was that I didn't have any 20mm fuses,
other than a 1A one from a shaver adaptor and they are not very
easy to find. I'm surprised at this because you would think they
would be very popular in shaver adaptors, especially now everyone
has electric toothbrushes, as well as shavers. I think office
clocks still use BS646 fuses too.

I've managed to order some 1.6A fuses, so it's a maytter of trying
them when they arrive.

The pump does not have the central screw. Instead it has a hex
head bolt. I'm not sure if that's how it came or whether that's an
"after market modification" by a previous owner/plumber, but it
seems to do the same job. I couldn't remove it completely, but once
I had loosed it, the shaft seemed to turn rather than the screw.

I suppose it wouldn't hurt to drain it and top it up with fresh
inhibitor. I'm just not sure whether this was a warning that the
pump is on its way out and whether to replace that at the same
time.

I was once advised by a plumber's wife (to save the call out charge)
to hit a seized pump with a hammer a few times. Did the job and it
carried on working.

Jonathan


Ah. The old joke.

Customer objects to $100 bill for hitting the water pump with a spanner,
so the bill is re-presented

"To hitting the water pump with a hammer -$1
"For coming out, knowing where to find it, and how hard and where to hit
it - $99

TOTAL $100


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The theory of Communism may be summed up in one sentence: Abolish all
private property.

Karl Marx