On Jan 6, 11:10*pm, The Natural Philosopher wrote:
YAPH wrote:
On Sat, 03 Jan 2009 14:20:18 -0800, Yekal wrote:

* Do you think I will be OK using the integral programmer? (which was
purchased seperate and now fitted), or will I need to get an external
one? as last time I spoke with Worcester they seem to think the
integral one won`t work withunderfloorheating.

I think you need to use a timer external to the boiler to control the
heating. From what I saw of your UFH controllers it looks as if they either
have or need to have their own time controls. If you just want the whole
house heating on or off at the same times then you can use one timer. If
you want zones controlled separately e.g. downstairs warm during day,
warmer in evening, practically off at night; upstairs background during
day, warm evening, cool night, warm morning; then I'd use separate
programmable thermostats for the zones.

After calcuating the time constant for my floors, which are screed andwetUFH with not a huge margin over whats needed in temps like this, I
decide to simply run the thing 24x7 on its own thermostatic circuit.

The overshoot is much less. - about half a degree instead of a degree,
and the heating isn't running as hard as it used to..
To be brutally honest, timingwetscreeded UFH is almost a waste of time
in the winter.

Probably far better to simply hard wire it to a thermostat and a switch.



Is the boiler a combi? If so you don't need a time control for hot water
(unless the boiler has some sort of pre-heat or storage function which can
be switched on & off). If it has, or if it's a conventional non-combi,
then you'll need a time control for that. BTW a "programmer" is
conventionally a device with independent timer controls for heating and
HW in one box.- Hide quoted text -

- Show quoted text -- Hide quoted text -

- Show quoted text -

Thanks everyone, got everything ready to go, but can`t get delivery of
oil till next week, then I will know if it all works!.