I am just moving house, and need to update the heating control on the new boiler (modem WB combi).
I am looking to make the system as efficient as possible, and will either zone upstairs/downstairs or uses TRV.
Previously I have used CM907 programable themostat, which gives multiple setpoints through the day and optimum start which give quite good control. However I am looking to take this one stage further.
In the past various companies have produced "load compensators" or weather compensators (including Valliant), however I do not beleive that this produce any useful savings on a moden system. How does the tempreature change outside, affect the heat requirements of the property? If the property is well insulation the change will be slow and will be picked up by the programmable thermostat inside the building. I believe weather/load compensators aim was to prevent cycling - a modem thermostat with proportional temprature control will prevent boiler cycling.
I am putting in some X10 stuff (basic remote switches), certain lights at dusk, garden etc, and my idea is to switch lights off automatically when the house is not occupied. Taking this one step further, I would like to be able to put the thermostat to a setback position when there is no occupancy (i.e thermostat is set to heat house to 20deg, but when no occupancy heat to
15deg). When occupancy is deteched (probably switch by the front door for the moment) then heat. Yes this means that you arrive back to a cool (not cold) house, but this will quickly recover - and whilst you are not in you are only heating to 15deg this saving gas.I did think about running the whole themostat using x10 - but this complicate matters, esp as the Honeywell thermostats do pretty good job (ie proportional control etc).
Does anyone have any idea how I can acheive this with X10? I have through about fitting a seperate manual (setback thermostat) set at 15deg.
If occupancy is YES, then use Honeywell CM907. If occupancy is NO, then use Manual 15deg thermostat.
Apprantly the CM907 can use an additional "Telephone interface can be fitted to allow remote switching, between program modes and a fixed set-point". But it appears that no one sell the telephone interface or that there are any wiring information on the net.. If this is just a simple contact switch (control by the seperate interface), then this may be ideal (switch to fixed set point when no occupancy). Does anyone know anything about these contacts.
Has anyone done anything similar?