What is the best way of making sure that the heat exchange is clean?
(sorry if this should be way too obvious!)


Well it starts to look like it but I just looked back through the
symptoms in the whole thread.

I think forget the thermostat for the moment - the safety cut out is
operating for a reason. Either it's faulty or the water flow is not
what you think and there is localised heating when the burner fires.

Given this situation, I would focus next on making sure that the heat
exchanger really is clean. Since you already said that you had
sludging in the bypass and elsewhere, I am thinking that this is the
next area to look and I would do that before buying spare thermostats
and cutouts.



What is a zone valve, and what are the controls to make my HW
connections more efficient?

It would be a two port motorised valve similar to the CH one, operated
by a thermostat on the cylinder. You then need to have appropriate
wiring with the boiler, pump and timer to hook it all together. I
would expect that the current setup that you have is very simply
wired. Have a look at the Honeywell web site and S-plan
configuration for two valves, or Y plan if you would prefer a single
divert valve. I wouldn't bother with this until the boiler issue is
resolved, though.







Regards,



(Danny) wrote in message . com...
Opp sorry, it should have been

http://dognet.no-ip.com/ch.jpg

Regards,


Andy Hall wrote in message . ..
On 4 Nov 2003 13:13:02 -0800, (Danny)
wrote:

Hi Andy,

I've sketched a diagram using word, its not too clevor but I'm sure
you'll see how my system is setup.

Visit http://dognet.no-io.com/ch.jpg

My boiler is just a standard traditional one

I've located the manual lever on the motorised valve and operated this
whilst the cover was removed, it sounded free from obstruction, the
cogs inside were turning. However when I let go the vavle returned to
the starting position and then a small amount of water came out of the
FE tank. Is this relevant to your diagnosis?

Regards,


Danny, is the URL correct? I am not getting this as a site that
exists (no domain name).......


.andy

To email, substitute .nospam with .gl

.andy

To email, substitute .nospam with .gl