Re: multi-zone central heating

[Kevin Hawkins <lists@xxxxxxxxxxxxxxxxx>]

Because when I open my current zone valves the inrush of hot water heats
my cast iron radiators up and they retain too much heat - causing a
significant overshoot in the room temperature. so my room temp is
oscillating quite wildly - by some 4 degrees. ( I guess in your analogy
the capacitor value is too large and the voltage applied too high ).   I
am also considering getting a better flow temperatue control but that is
problematic too. Although  I do have boiler modulation control I have
some (cold) rooms that can generate a demand for heat from time - and
they need a high flow temp to warm them up quickly.    I sure Smart
Kontrols would sort it for £25K   ;-)

Ake Hedman wrote:

>Kevin,
>
>but why do you need linear control. Isn't it enough with open/close and
>control room temp. using the derivate of the actual temperature. If you
>think of the radiator as capacitor this will work much the same as PWM
>in electronics and give "sort of" the same result energy
wise.
>
>/Ake
>
>
>