Vokera Boiler and Nest 3rd Generation - HELP!

[A_Guy_In_London]

Hi all,

So looking for any advice/suggestions you might have about the following. I'll try to keep it short and to the point. Brand new central heating system installed in May this year. Vokera 32C Evolve Combi Boiler and Nest 3rd Gen. From the time the boiler and Nest was installed the house has undergone extensive renovation so I am only now powering up the boiler to provide heating.

So the problem I have is with my Nest. It appears to be working to a degree however when the temperature reaches what is set on the Nest - or - If I turn the temperature down on the Nest, the boiler completely switches off. Complete power loss.

If I turn the temperature back up it comes back to life again but begins a start-up cycle. Obviously when the boiler is off there is no hot water being supplied.

Had a plumber in today to pressurize the system and he saw what was going on and said 'that's not right!'.

I can't seem to find anything online that relates to this type of issue so I am coming here for any assistance or guidance that can be rendered!!

Thanks for any comments you might have and waiting with eager anticipation

 

[Razor900]

It's wired up wrong but you already know that

Sounds like the permanent and switched lives are mixed.

If he's around @vulcancontinental will be able to tell you what should go where.

It would help if we knew what the wiring was like now

 

[A_Guy_In_London]

Ok, that doesn't sound too disastrous? I will try and take some photos tonight. Forgive my ignorance but are we talking about the heatlink having the incorrect wiring?

Thanks very much!

 

[ianmcd]

I doubt if the problem is with the nest, you were ill advised to have a nest fitted, you would have been better off with Vokeras own Besmart, I will leave it to as already advised @vulcancontinental to explain why, you can still have nest installed but will not have as many functions and takes a bit of work to get a nest to work properly with your set up but can be done

 

[A_Guy_In_London]

Ok, I will wait for @vulcancontinental so see if he can give any advice. Thanks for your time!

 

[vulcancontinental]

I first of all recommend getting a pro in it's simply easier and less haasle.

Post a picture please of the Nest heat link and the cable from the bottom right hand side of the boiler to the power supply. Also a picture from beneath the boiler on the left hand side looking up (There's a white terminal box)

I have a course tomorrow so will have no time but Friday I can get the Nest out of store and reaquaint myself with the wiring to give you more concise advice.

Basically it will be two wires from the Nest heat link to either terminals TA or OT. They have to be correct because if you make a mistake and put 240 volts into them the boiler pcb is toast. Be careful with this.

 

[A_Guy_In_London]

Hello! So apologies for the delay..... Here's a picture of the Nest wiring. The nest cable enters the boiler by some sort of junction box which I cannot figure out how to get access to - will have another go later today. @vulcancontinental - really appreciate your help with this!

 

[ianmcd]

its not the nest you need a permanent live to the boiler,