This is just a quick rank i had on a forum about weather comp:
The advantage of weather compensation over s-plan heating controls (timeclock & thermostat) is that is a predictive control for house temperature instead of a reactive control that will will get a standard heating controls.
Traditional heating system sequence of events:
1. Outside temperature drops
2. More heat is lost through the walls & windows
3. Rooms get colder – which is detected by the room thermostat
4. Thermostat ‘tells’ the boiler to fire/work harder (if timeclock allows)
5. Rooms get warmer again
In the above example, it isn’t until stage 4 that the boiler gets any ‘feedback’ and is able to respond to changing conditions.
The chances are that at this stage, the householder will be feeling the cold and will turn the thermostat up even further – wasting even more fuel.
If the outside temperature rises, the boiler will not respond until the rooms have become uncomfortably warm – so in addition to
adjusting thethermostat, there’ll probably be the temptation to open some windows, releasing more heat and wasting more energy
Weather Compensation Control
1. Outside temperature drops – which is detected by outdoor sensor
2. HP/Boiler will come on sending heat into house
3. Radiators get warmer to compensate for heat lost*
4. Room temperature is maintained
Therefore weather compensation is only looking to send in just the right amount of heat into the building, no more nor no less to keep it at a contant temperature. Various forms of heat pumps then will have temperature set backs built in that will allow greater use of night rate electricity.
WCC (weather compensation controls) will always be looking at the outside temperature (main factor in heating demand of a building) and calculate a desired flow temperature into the UFH/rads, this calculated flow temperature will increase in cold weather and decrease in warm.
The WCC will them compare the actual flow temperature in the rads/ufh (which reflects building temp) and compare it with the desired flow temperature (based on outdoor temp and homeowner setting) and run the heat pump if deemed necessary.
WWC is the only cost efficient way to control UFH.