understanding electrics

[Chris_59]

Hi, I intend to renew a very old junction box, to fix a mess of wires left over from the initial central heating installation, but first I need to understand what controls what.

So I am really looking for a bit of advice really from you experts out there.
I have an old gas boiler and storage tank and radiator system. I have recently upgraded the control system to a Hive stat, and now intend to tidy up the wiring in phase 2, phase 3 will probably be the motorised valves.

So I have worked out that I have control wires for each hot water and heating valves, and another for the tank thermostat. What is a little confusing is how the pump is controlled. Is this on all the time, or only when needed. So in order to answer the question, where does the power come from.

Any advice greatly appreciated.

regards
Chris

 

[ianmcd]

need more info, make and model of boiler

 

[Hugh Jaleak]

As above, there are so many possible variations, whilst the standard wiring plans exist, allowance has to be made for differences when using certain components. 2 and 3 wire stats, some boilers control the pump to provide pump overrun, so require a constant live feed, a switched live for when heat is required, and then return the live feed to power the pump as required. Without more knowledge of your system, it is impossible to say.