Potterton suprima boiler and Tado problem

[Deleted member 101754]

Hello,
So I swapped out the Original thermostat for a Tado Thermostat last night to my Potterton suprima 40 boiler (conventional non condensing) and and everything worked fine for about an hour then the heating breaker tripped on my fuse board. I turned the boiler off and flipped the breaker back on but now I've no power to the Thermostat and the heating won't fire up at all (Hot water still works). Could the Tado system have popped a fuse on the circuit board or worse fried the heating part of it?
I've slid the 3 way valve next to the hot water tank to manual bypass so at least there's some heat coming through the radiators with the hot water on but looking for suggestions as to why a smart thermostat would fry a boiler pcb like this.
I've had to fit 3 reconditioned pcbs to this old cantankerous boiler over the years so not a complete stranger to the insides of it.

 

[Harvest Fields]

Check all wiring on the tado? Have have you wired it in?

 

[Deleted member 101754]

Yeah the wiring is fine I'd followed Tados simple instructions (only the 3 wires) and it worked for around an hour before tripping the fusebox. I should have said, the Tado is battery operated and just sends the signal to turn the boiler on. I've swapped my old thermostat back on and it's still dead. photo of the old wiring which has the brown jumper cable which Tado didn't need.

 

[Harvest Fields]

Is the tado 24volts. As that connection is 240volts

 

[Deleted member 101754]

Pretty sure it's 240, this is how they told me to wire it up. You put in what boiler and controllers you have and they give you step by step instructions.

I've reconnected the old thermostat but the heating won't come on

 

[Harvest Fields]

Pretty sure it's 240, this is how they told me to wire it up. You put in what boiler and controllers you have and they give you step by step instructions.
View attachment 35683
I've reconnected the old thermostat but the heating won't come on

And there is your issue right there. You need a heating engineer to fix your issue mate

 

[Deleted member 101754]

what did I miss? what's the issue?

 

[Harvest Fields]

No offence intended mate. But you now need someone that knows what they are doing. Sorry.

 

[AMGasServices]

Do you have an extension kit ?

If so I think that should be jumper position 2 (240 volts)

Secondly you don’t need a cable in nc you would need to put it in a blank spot.

The COM is your common usually has 240 on it. NO sends power back to the controls to come on.

From looking at the old stat yellow wire appears to be your common and red wire to calling.

The blue wire is not needed put it in one of the blank ports.

 

[Deleted member 101754]

Thanks for your suggestion Harvest Fields.

AMGasServices,
Appreciate your reply. Sounds like the Tado instructions are incorrect, I've raised a ticket with them so we'll see what they come back with...
No I didn't get the extension kit, just went for the thermostat, my hot water is still using the old Potterton controller in the linen cupboard and thankfully is still working.
Given I've refitted the Original and it's still gubbed I have a suspicion something on the pcb has gone (this is the 2nd reconditioned one it's had in it's long 20 yrs of service) or if I'm really lucky the little glass fuse on it? I'll have a look tonight and see if there's any scorch marks and check that fuse. If I can't spot anything obvious from that I'll call someone in. Was hoping one of you on this helpful forum might have seen this sort of thing happen before and give me some pointers on what to check.

 

[ShaunCorbs]

Remove the blue wire and make it safe eg choc block

In short you've connected the live and neutral together

Also trim them conductors no copper showing

You could of blown your pcb best to get an engineer out

 

[Riley]

Yes stay out of your boiler

 

[Deleted member 101754]

Thanks ppl, my bad. Engineer coming out to fix my "male chicken" up. I'll leave it to the experts!

 

[PETE 123]

Is the blue a n if so that would blow fuse