Heatrea sadia.....heating off but rads hot

[Dee]

Hello,

The house has a heatrea sadia system (with a red expansion tank) and a worcester bosh boiler.

The issues are.... 

There are two power switches next to each other and the tank. One is permanently on and the other person off. What are they for??? 

 

Secondly the boiler is often firing ?  but the timer control is off but the rads are hot....!!

 

I'm desperately trying to save on heating and hit water but I don't understand this system.

 

I want to be able to heat water only when I need it but it seems to heat twice every day whis is far too often.

Thanks

[ProDave]

Context please.  Is this a new system that has never worked properly, or it has previously worked perfectly but started to misbehave?

 

The 2 switches on the tank are probably immersion heaters.  If you are heating the hot water from the boiler these should both be off.  Post a picture of the tank and the switches to confirm that.

 

Also post any pictures of anything else related like motorised valves?