The (new build) house we have just bought has underfloor heating
downstairs and a conventional TRV/thermostat arrangement upstairs; I
guess this setup is quite common. However, the thermostat (and the
uncontrolled radiator) are on the galleried landing, which receives a
significant amount of heat from the UFH in the hall below. Therefore
there is a tendency for the bedrooms to go cold when the UFH is
running, unless the thermostat is turned up.

Is this a sensible arrangement? I would have thought the thermostat
and uncontrolled radiator ought to be in a zone isolated from the
influence of the UFH.

Richard.
http://www.rtrussell.co.uk/
To reply by email change 'news' to my forename.

Russel
I am no heating expert, but I would have put the uncontrolled radiator
in the bathroom (perhaps as a towel rail). I doubt the landing is
being affected too much by the downstairs UFH. I am assuming that each
zone downstairs has its own room stat? Is there one pump for the whole
system, or is the top and bottom controlled by a pump each (ie does
the UFH manifold have a pump attached to it?). To sort your problem
without too much work I would be tempted to restrict the flow to the
radiator in the landing by screwing one valve partially down, but
making sure there is still adequite flow so as not to risk any damage
to the system. Trial and error over a day should get a good result.
By the way, it is quite normal to have the stat near the uncontrolled
radiator since the last thing you want is the TRV kicking in before
the controlling stat.
Good luck
Calum Sabey
NewArk Traditional Kitchens

Richard Russell wrote:
The (new build) house we have just bought has underfloor heating
downstairs and a conventional TRV/thermostat arrangement upstairs; I
guess this setup is quite common. However, the thermostat (and the
uncontrolled radiator) are on the galleried landing, which receives a
significant amount of heat from the UFH in the hall below. Therefore
there is a tendency for the bedrooms to go cold when the UFH is
running, unless the thermostat is turned up.

Is this a sensible arrangement? I would have thought the thermostat
and uncontrolled radiator ought to be in a zone isolated from the
influence of the UFH.


Yup.

I had a similar problem. You should install a separate stat for the UFH
(or the rads) as you say 'when the UFH is running' which implies its
separately pumped and switched.

A radio stat is ideal.

My UFH typically has a 4-6 hour lag between coming on, and getting to
proper temperature, so you need a split zone and a different timer anyway.



Richard.
http://www.rtrussell.co.uk/
To reply by email change 'news' to my forename.

On 22 Dec, 01:23, The Natural Philosopher wrote:
I had a similar problem. You should install a separate stat for the UFH
(or the rads) as you say 'when the UFH is running' which implies its
separately pumped and switched.

The UFH already has a "separate stat" (six of them in fact, one for
each zone); it's completely independent of the upstairs heating (apart
from the boiler!), having its own pump and zone valve. The influence
of the UFH on the rads is purely because heat from the hall is
affecting the thermostat, which is mounted on the galleried landing
near the top of the stairs.

A radio stat is ideal.

The UFH roomstats are all battery powered (though not wireless) so
that's already six sets of batteries to change every so often, and six
clocks to adjust twice a year! Adding yet another battery-powered
device isn't my definition of "ideal".

I'm very tempted to move the thermostat into the upstairs room which
takes the longest to heat up (and to make that room's rad the
uncontrolled one). That way all the other rooms should have reached
their set temperature, under control of the TRVs, before the
thermostat switches off the flow.

Richard.
http://www.rtrussell.co.uk/
To reply by email change 'news' to my forename.

Richard Russell wrote:
On 22 Dec, 01:23, The Natural Philosopher wrote:
I had a similar problem. You should install a separate stat for the UFH
(or the rads) as you say 'when the UFH is running' which implies its
separately pumped and switched.

The UFH already has a "separate stat" (six of them in fact, one for
each zone); it's completely independent of the upstairs heating (apart
from the boiler!), having its own pump and zone valve. The influence
of the UFH on the rads is purely because heat from the hall is
affecting the thermostat, which is mounted on the galleried landing
near the top of the stairs.


OK.. thats fair enough..

A radio stat is ideal.

The UFH roomstats are all battery powered (though not wireless) so
that's already six sets of batteries to change every so often, and six
clocks to adjust twice a year! Adding yet another battery-powered
device isn't my definition of "ideal".


I said stat, not timer..surely you have a timer for the upstairs zone?
just take the stat from where it is and put it somewhere else.



I'm very tempted to move the thermostat into the upstairs room which
takes the longest to heat up (and to make that room's rad the
uncontrolled one). That way all the other rooms should have reached
their set temperature, under control of the TRVs, before the
thermostat switches off the flow.


Sounds reasonable. I must say stats and TRVs don't go together very well.

I have an odd system here. No upstairs stats to control pump at all.
TRVS, and thermostats on fan blown heaters. The pump runs all the time.

What you MIGHT do is take a bathroom and simply use that as a bypass..if
its a very small room and it gets too hot, open the window..and forget
stats altogether.

We leave the upstairs off entirely most of the time,. just hitting the
'boost' button for an hours worth of steamy bathrooms when required, or
just before going to bed - apart from ultra cold weather.


Richard.
http://www.rtrussell.co.uk/
To reply by email change 'news' to my forename.

On 22 Dec, 16:38, The Natural Philosopher wrote:
I said stat, not timer

I know. It was the batteries (in a wireless stat) I was complaining
about. Everything these days seems to need batteries. Personally I'd
prefer everything to be wired and mains powered (with a rechargeable
battery or supercap to hold settings through a power cut).

surely you have a timer for the upstairs zone?

Bog standard water/heating timer next to the boiler. The only options
are off/continuous/once/twice although I could presumably replace it
with a more sophisticated model if necessary.

Sounds reasonable. I must say stats and TRVs don't go together very well.

It's the normal arrangement, though, isn't it? Admittedly it does
seem a bit penny-pinching to fit a multi-zone multi-stat UFH system
downstairs but a basic stat/TRV system upstairs.

Richard.
http://www.rtrussell.co.uk/
To reply by email change 'news' to my forename.