new valliant boiler & rads help please

[MJN]

Your boiler has an ABV inside it.

Regarding TRVs you would not normaly have one in the room where the stat is (unless the TRV is kept on full, ideally with the head removed) so that they don't fight each other (e.g. TRV thinks it's too warm and so turns the rad off, but the stat thinks it's too cold and fires the boiler to apparently little effect).

Given your mention of TRVs everywhere, do you have a room stat? You ought to for various reasons, not least of which compliance with Part L of the building regs.

Mathew

 

[Agile]

I am going to rather unusually disagree with my learned friend Hailsham.

In this instance he does not seem to have made it clear that current systems should ideally be designed for adequate heat output with a flow temperature of 75 C and a return of 55 C.

Your nupty installer has apparently been using figures of 80 C flow and a 11 C diferential which used to be used for NON-condensing boilers. He seems way out of date!

The figures on the Benchmark are only those used for testing and have no relevance to design parameters.

I think that your boiler has an internal bypass. Whilst many installers rely on that alone, I have always thought that an external one as well was better and indeed many installers do fit them. ( Though this may be because they dont know there is one in the boiler ? )

Tony Glazier