On Tue, 6 Oct 2009, Michael Chare wrote:

We stayed in a house with this system this summer, the radiator
without a TRV was the biggest one and gave out heat regardless of
how warm the house was.

The only thing I could do was to set the boiler temperature lower,
or switch the boiler off completely.

Isn't this a "simple" tuning issue? Does one have to have the biggest
one as the by-pass? I just have my bathroom rad TRVs higher than the
rest and I also have a small, tuned down radiator with no TRV in the
hall where the room stat is.

--
Kostas