Phil Addison wrote in message . ..

Have you actually followed the detailed procedure, or is the above all
you have done?

I pretty much summed up all that I've done in my first para - i.e.
just closed down the LSVs on the hottest (ground floor) rads, hoping
that would force some hot water to make its way up to the second
floor. I've not done any proper temperature readings (except using my
hand!). All of the go/return plumbing is concealed below the
flooring, so I cannot tell how the plumbing is routed. There is about
a meter of exposed 'main' pipework near the boiler and I guess the
external diameter is about 25mm.


If you *have* followed the FAQ procedure, it seems that there is some
inadequacy in the plumbing design. To track this down, try the
following:

Turn off the boiler.
Open both valves fully on one radiator and close down all the others.
Turn boiler back on.

If that radiator heats up, repeat for each of the others in turn.

I tried that last night - with all the others locked off, my top rads
heat up nice and hot. So no blockages, airlocks, etc.


The boiler size would only be a problem if it is firing continuously
flat out and the radiators are still not getting all equally hot.

This does seem to be the case.


If that does not help you will need to give us much more details of the
system and what it is doing.

OK: I have 10 rads on the ground floor (double panels ranging from
50cm to 120cm, and a 200cm single panel), 2 on the first floor and 2
on the second floor. And a chrome towel rail on each floor. The
boiler is a Worcester Highflow 400, running off LPG (costs a
fortune!). It has an built-in pump which is not speed adjustable.
(The manual says "if there is a switch, it will be factory set to
maximum and should not be adjusted".)

The whole system was brand new about 18 months ago. I had the same
problem all last winter (we had to get electric heaters on the top
floor!). Surely whoever installed it would have used an adequate size
boiler? It's physically much bigger than in my last house -- and that
was a 3-storey house too. I wonder whether the problem is that there
are so many more rads on the ground floor than on the upper floors?

Thanks again,

Simon.