Vailliant sustain 418 heat only problem

[diycooper]

Yes, which can most often be taken from the wiring centre.

Granted there are setups where pump is elsewhere, but not often.

Other boilers such as Main do not require a permanent live and/or pump overrun as their hex dissipates heat via the fan or just doesn't get too hot.

Vaillant have pcb firmware that requires very tight limits from NTCs to protect the hex which is vulnerable due to design and construction.

Well that's annoyed me as I was originally putting in a Main ha

 

[diycooper]

Correct.
But the 3 way kit utilises the existing 3 core if there is one between boiler and cylinder... Whereas you'd otherwise need triple.

At boilor I have live neutral earth switch live

 

[dilalio]

At boilor boiler or heat source/engineI have live neutral earth switch live

OK. Then, imo you can utilise the 3 wire kit, but I've not had the benefit of eyes on your system so... It's all advice at distance!

 

[diycooper]

OK. Then, imo you can utilise the 3 wire kit, but I've not had the benefit of eyes on your system so... It's all advice at distance!

Thanks. It would take abit longer to sort even though if knew how to do it I would go down that route.

Got my spark friend throwing the cable in tomorrow for a £100.

 

[dilalio]

Got my spark friend throwing the cable in tomorrow for a £100.

Then it's a no-brainier!
Can he wire it up or just run the cable?

 

[Johntheo5]

At boilor I have live neutral earth switch live

And (a) PL, where the cable is be run from to the circ pump?.

 

[diycooper]

Then it's a no-brainier!
Can he wire it up or just run the cable?

Vailliant engineer will wire it in for £50. So £150 cable in and wired. Job done

 

[diycooper]

And (a) PL, where the cable is be run from to the circ pump?.

Not other cable at boilor. Just the 4.

 

[diycooper]

And (a) PL, where the cable is be run from to the circ pump?.

If yiu mean I will have a circ to PL once cabke it . Correct.

Thanks