On Thu, 27 Nov 2003 17:49:43 +0000, rober wrote:

Hi,

I have a Saunier Duval Thelia 23, the central heating is working fine,
however the hot water is not.

When in Central Heating & Hot Water mode, the HW is almost
at mains temp, slightly above, when in HW only it is the same.
The HW temp control has no effect at all.

However putting it into HW mode and putting the CH temp
control to halfway, (usually is at 1/4)you get HW bouncing between
cold and hot and very hot radiators. The HW temp control has no
effect in any mode. Using it in the unorthadox CH burning hot it
makes a banging noise upon providing HW then gets cold then
repeats.

Any ideas on how I can fix this, don't want to run the gambit of
£50 call out fee's, getting a £300 repair bill and all. After installing
a doubleglazed window for about 10% of the cost 3 quotes wanted
i'm not in the mood for calling the professionals

As a pro I would be looking to check out the temperature sensors.
Likely they are NTC Thermistors perhaps they are both on the blink?

I suspect that if you turned the CH any higher you would get an overheat
lockout.

If you really need the installation and servicing manual.

--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html