central heating problems

dsbp1962

In brief... just had newly purchased house renovated including new boiler- Vaillant ecotech 450 - new rads, hot water cylinder, controls etc. For the first 3 weeks the heating didn't work (water always fine) and installer replaced all external controls one by one to no effect. Said goodbye to installer when I discovered that the cylinder thermostat was set too low, one small turn and everything fine for 3 weeks although rads never get really hot and system never reaches room stat setting. Since yesterday the boiler will only fire up if I manually tweek the cylinder stat - boiler works til it reaches its setting then switches off and doesn't restart when temp drops. Any ideas????? In not too technical terms please!

macman

Your boiler has at least a two (possibly five) years manufacturer's warranty, assuming that it was fitted by a Vaillant-qualified GSR RGI, and fitted according to the book. Was the Benchmark paperwork completed and handed to you?
If you have paid the original installer in full (which your post implies that you have done), why did you do that if the system has never functioned properly?
The setting on the tank 'stat simply controls your hot water temp, it should have no influence on the water temp in the CH circuit, which is where the problem appears to be. Nor is it influenced by the ambient temperature of the property.
Rather than scratch your head, I'd get Vaillant out to look at it-though it may be that the fault lies in the external controls rather than the boiler itself.
What programmer is fitted?

gas4you

Never heard of an Ecotec 450.

What is it actually?

Most common problem with these is that the installer fits one that is too big for the system and the boiler then sits at S53 for ages, doing nothing, because of the incorrect temperature differential.

dsbp1962

Installation was done by Vaillant approved Gas Safe installer however there is no problem with the boiler - no error codes and boiler responds to the external 'messages' it receives but I think those messages are wrong.

The installation was done before I moved into the property and I took it as read from the installer tbat the system was up and running.

macman

But if you commissioned the installer (not the previous owner) then the installer needs to supply you with the Benchmark documentation. Without that your warranty is worthless. What did he supply to you?
I cannot quite believe that you paid the installer several thousand pounds in full without even seeing if the heating was operational for yourself.
I don't understand why you haven't got the installer back to sort the problem out, since he has been willing to do so? If not, and it's not a warranty issue, then you will have to pay someone else to put it right.

dsbp1962

Thanks for your comments and you are right - I need to chase the paperwork for the boiler. With regards to the installation, this was part of a 4 month renovation which was full of problems - the installer came back at least 10 times to replace various controls and I think was a bit embarrassed when I initially solved the problem by turning the cylinder thermostat up from a very low setting. Haven't seen or heard from him since!

Avoriaz

dsbp1962 wrote: »

...Said goodbye to installer when I discovered that the cylinder thermostat was set too low, ...

dsbp1962 wrote: »

...the installer came back at least 10 times to replace various controls and I think was a bit embarrassed when I initially solved the problem by turning the cylinder thermostat up from a very low setting. Haven't seen or heard from him since!

Your first post suggests that you sacked the installer which could explain the highlighted part of your second post.

Get him back and give him the opportunity to rectify the remaining problems.

macman

The Benchmark documentation should be handed to you on completion of the install and commissioning-it's not acceptable to complete it retrospectively.
Are you sure that this RGI is GSR-did you actually check his reg online? Has the boiler been reg'd?
He's not been back since, because he has no incentive to sort the problem out.

C_Mababejive

This doesnt sound good.....

daveyjp

C_Mababejive wrote: »

This doesnt sound good.....

Agreed, especially when it appears it has never worked and there is no commissioning documentation.

OP, have you had a welcome and warranty confirmation letter from Vaillant yet? Your Vaillant approved RGI should have sent the paperwork to Vaillant following install so you get the 5 year cover, rather than 3.

gas4you

When the boiler is just sitting there and not firing up when you think it should, press the 'i' button an see what 'S' code is displayed.