Problem: ‘back-boiler’ heats HWC to above 95°c, which trips the immersion heater safety cut out.
Solution: fit thermostat the HWC/primary flow, so that when temperature reaches (say) 75°c, thermostat tells the CH pump to ‘turn on’ and divert the hot water from the HWC to CH.
Question: how to wire the thermostat, with a permanent live connection so that in the event of a overheat situation, the pump is activated, irrespective of whether it is turned on at the ‘double- pole switch’, thus dissipating excess heat quickly through the radiator circuit and prevent boiling the WHC.
There are three terminals on the thermostat wiring:
1. Common inlet.
2. Outlet (opens the circuit with increasing temperature).
3. Outlet (closes the circuit with increasing temperature).
Where does wire 1 connect to? (on the double- pole switch)
Where does wire 2 connect to? (on the double- pole switch)
Where does wire 3 connect to? (on the double- pole switch)
So the question is: where do all the wires need to come from and go to?
DIY how to tutorial projects and guides - Did you know we have a DIY Projects section? Well, if no, then we certainly do! Within this area of our site have literally hundreds of how-to guides and tutorials that cover a huge range of home improvement tasks. Each page also comes with pictures and a video to make completing those jobs even easier!