Thread: Baxi Solo 3 PF
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John
 
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Default Baxi Solo 3 PF


"Set Square" wrote in message
...
In an earlier contribution to this discussion,
Darren Griffin - PocketGPSWorld wrote:

geoff wrote:
It certainly seems to be the first thing to look at

If you are confident enough with electricity, you could try
connecting it up to the mains (via a plug with a 5A fuse in (unless
you like big bangs))

If it blows the fuse, you've found your problem


OK, firstly I now appear to have blown the PCB, tested last night
without pump connected and all was OK, switched off, connected pump,
switched on and there was a pop, noticed fuse on PCB had blown so
replaced and even without pump conncted this time there was no light
indicating Boiler ON, removed PCB and there is a small burn mark
towards rear around two resistors, so I'll be needing a recon
replacement from you for starters! (Baxi Part: 231711).

As for the pump, disconnected, attached plug (with 5A fuse) and
connected to mains, as soon as it is switched on the master trip in
the CU activates although the 5A fuse does not blow! This obvioulsy
suggests the pump has a problem but my electrical knowledge is not
good enough to explain why the fuse remains intact. The good news is
there are valves directly above and below the pump so a full system
drain is not necessary.

Would you agree that the pump appears to have been the culprit here?
I'll source a new replacement, it's a Grundfos Selectric UPS 15-50
and hopefully this should be relatively simple to replace. As for
the PCB, I'll contact you directly regards a replacement.


Why, oh why didn't you follow the advice of testing the pump on its own
FIRST? You'd have saved yourself the cost of the new PCB for the boiler!

The pump almost certainly has a short between live and earth. The mains
socket you plugged it into is probably protected by an earth leakage
breaker - which tripped before the fuse blew. The central heating - along
with freezers etc. - is probably on a circuit which doesn't have earth
leakage protection - causing the fuse to blow instead when the pump was
normally connected.

You'll need a large spanner (or adjustable) to undo the nuts on the pump -
and they might take a bit of shifting. It often helps to have an assistant
to hang on to the pump while you tap the spanner round with a copper

mallet.
Make sure that you replace the (rubber or fibre) washers between the valve
flanges and pump body - and try not to strain the surrounding pipework

more
than absolutely necessary - since this can induce leaks elsewhere.


shut off the service valves and hope they don't leak through the spindle
when you move them if they are more than a couple of years old. (Try to do
the job when merchants are open to buy replacements if they do).
Sometimes the nuts move easily but often they require a bit of tapping with
a small hammer to break the crud seal which may have formed on the threads.
With a bit of practice you can strike it on the "corners" to persuade it to
undo. Ensure the new pump goes back in the same flow direction as per arrow
on body and apply grease to the threads to facilitate future removal. Most
pumps come with 2 new joint gaskets in the box but make sure the faces of
the old unions are clean. Its sometimes easier to fit the wiring while the
pump is loose and easy to work on. Refill and vent the pump through the
spindle plug then away you go.