Hi
I did call out worcester Bosch to do the repair, well worth it. Two
fixed prices, £185 for a minor repair, £245 if a heat exchanger is
faulty.
In my case the water to water heat exchanger was changed, then noticed
that the heating not switching correctly, so traced the fault to a
braided hose going to the expansion vessel, totally blocked. Also
changed the diverter valve and relief valve which were also sticking.
Think I had my moneys worth there, as it took 41/2 in total.

He thinks that the main problem is due to some black sludge in the
heating system. This was all flushed when the boiler was fitted 3 1/2
years ago, but he reckoned that this is the normal cause with combi
boilers malfunctioning. About 5 radiators have also been fitted new
since the boiler was installed.
He recommended having the system power flushed which I know is very
expensive, but is it really worth it?

Surely it would be easy enoughto flush it through myself selectively
closing radiator valves after leaving it for some time running with
Fernox restorer? The boiler is also situated on the upper floor so
would that help?

cheers

















On Mon, 20 Nov 2006 23:32:44 +0000 (UTC), Ed Sirett
wrote:

On Mon, 20 Nov 2006 15:23:22 +0000, jack wrote:

I have a Worcester Highflow 400 which is only 3 years old and it has
suddenly developed a leak. It seems to be dripping below the "water to
water heat exchanger" towards the aft end of it away from the 2
manifolds firrted on the front face of it.

Struggling at the moment to get someone out to repair it so getting
the feeling that I will be doing it.

Has anyone on here replaced one, how easy, how long to do it and is it
a common fault?

Are these also called the plate exchanger?

Try calling Worcester they have a service dept.
A fair bit of dismantling is required although I've not done one.
Looks like you need a lot of new O-rings.