multiple thermostats

I have a thermal store heated by a boiler with its own thermostat. I also have a stove with a back boiler. The stove heats water in a separate tank. There is a thermostat on this second tank that pushes hot water over to the store tank when it's hot. It's a closed loop and goes through a heat...

House is in 4 x sections. 4 x Thermostats. I not starting the boiler. Have switch out the broken section to another section and it starts that other good section. Have put good pair on bad section, no start. Have pulled out the mass of wiring and checked all connections are good. They are. Have...