Is this wired right

[deanalewis]

Heya

I fitted a Hive thermostat and things look too work ok... However I find that when the thermostat turns off for heat the boiler and the pump both stop at the same time.

This is because the pump is going through a terminal block with the boiler... The pump live then goes through a normal on off switch up to the hotpress.

But why would it be linked like this... I have been out at the boiler and the pipes are very hot.

Presumably the pump should run after the thermostat reaches temperature for a bit too dissipate heat.

Just wondering has this been linked wrongly in the past.

On my hive wiring I also don't have anything going to common just live neutral and boiler/pump going to 3 on the wiring.

I have an oil boiler so the pump is in a separate location to the boiler

Any ideas

 

[CountryFan]

Did you have an existing thermostat? Doesn’t sound entirely correct, but oil aren’t my specialty. Not all boilers require pump overrun.

 

[gas112]

look at your boiler instructions not all boilers need a pump over run

 

[Exedon]

look at your boiler instructions not all boilers need a pump over run

As above but I very much doubt you oil boiler requires a pump overrun . The water capacity of oil boilers is huge compared with gas boilers.

 

[ericmark]

I was advised not to have a motorised valve on the DHW as the boiler would cool by heating the DHW, I have a C Plan, the same will happen with Y Plan thermo-syphon will mean water still moves even with pump turned off.

Only the motorised valve will stop flow. And only with S Plan.

 

[Exedon]

Better be clear re motorised valves.
The standard control system for heat only/system oil boilers is S plan .
The number of oil boilers we have installed over last few years is well into 4 figures.
The only time I've known a oil boiler overheat stat work is
Failed boiler stat
System circulation problems (pump issues or air locks)
We fit a auto bypass as standard but only definitely needed in a full trv system.