re: fitting digistat +3 to Vokera Linea 24

[heatingman]

The following relate to term strip inside boiler.

N.....neutral input from fused spur.
N.....neutral to integral clock(blue) ..remove
L.....240v input from fused spur.
L.....240v to intgral clock (brown) .....remove
TA...wire from digistat term on
TA...wire to digistat term C
=...empty
there must not be any other link wires.

pull the brown/blue/black wires of timer and pop in tool box. Leave the timer in situ (to fill hole) unless you still have blank.

Sorry about that, the batts are purely to maintain display in unit when powered down by timer

john

 

[alexthompson]

why is there a link wire between the = & TA when the internal timer is used, but not when the Digitstat is used?

 

[heatingman]

When the boiler came out of the factory it was ready wired with the link across TA and TA any external controls would be wired across TA/TA and the link discarded. The = term is purely a junction terminal,used so there are no wires/joints flapping about. For whatever reason someone has left the link in which has caused the confusion.

 

[alexthompson]

John

Many thanks for your help. I've played stupid just to confirm that how I wired was correct, which I believed it was. Now the question is the real issue to my problem, the PCB control board blowing. 2 boards have blown since the Digistat was fitted. The boards blow under this situation.

1. The boiler is turned off at the main.
2. The Digistat still displays settings as it's battery powered.
3. The Digistat clicks to fire up the boiler (the boiler is still powered off)
4. The PCB control blows.

So the real problem is could the Digistat be faulty, causing the boiler to blow?
If not, could it be possible the boiler is not grounded correctly, so when its turned off, and the Digistat fires through a short current resulting in the PCB board blowing?

 

[heatingman]

If the powers off, the digisat is not switching anything so I dont see how pcb can blow. Are we talking off at the mains spur. Re-check your wiring, the digistat is purely a switch and the batts do not have enough power to take out pcb

 

[alexthompson]

Yes off at mains spur.

Well the Digistat is blowing it for some reason.
I'm going to replace the Double pole switch tomorrow, and replace the wiring between the boiler just so I know its done right. Ive double and double checked all wiring to the board and all is correct.

If the Digistat is switched off, I can switch the boiler On and Off at the mains as much as I want without any problem. As soon as I put batteries in the Digistat and fire up the heating with the boiler powered off, PCB blows.

I'm at a complete loss here.
I was gonna install a Switch between the Digistat and boiler so I can switch it off without removing the batteries, but this seems stupid. Could it be possible the Digistat is faulty and frying the PCB boards? I'm pushing this as I've folked out near £200 on this now, and sitting with no heating and hot water for 2 says solid again?

Many thanks

 

[heatingman]

Give Vokera tech a call, there based up your end and will no doubt know if theres been any issues with drayton stat.
Good luck

 

[alexthompson]

John

2 final questions.

1.Would it make a difference which TA the Digistat C and On are connected too?

2. If the PCB was not earthed, could it be possible this is why the Digistat is frying the PCB board. If yes, is there any way to verify Earth wire is grounded using Multimeter or such device?

Many thanks for your help and staying up late.

Cheers

Alex

 

[heatingman]

If the PCB had no earth it wouldn't fry it, there are earths all over boiler so dont worry about that. The pcb will have earths where req.

The following relate to term strip inside boiler.

N.....neutral input from fused spur.
N.....empty
L.....240v input from fused spur.
L.....empty
TA...wire from digistat on
TA...wire to digistat term C
=...empty

Wire as above.

there must not be any other link wires.

Sorry about that, the batts are purely to maintain display in unit when powered down by timer

Not repeating myself just pasting its quicker
Do you have a multi-meter.
john

 

[alexthompson]

yes i have a multi-meter.

 

[scaby]

disconnect the live and neutral from the digistat, the stat doesnt need a 230 volt supply, the stat is only switching the low voltage supply from the boiler, you might have fried the pcb by putting 230v down the low voltage contacts

 

[alexthompson]

there is no L or N as it's the battery model.

 

[scaby]

if you have the digistat terminals c and on connected to the ta terminals , and all other links removed , the only thing left is the built in time clock is still connected ,it has to be disconnected

 

[alexthompson]

they are.

im at a loss. I've a third PCB board, just bought today, I'm gonna do the test again then issue a legal claim for cost to Drayton, as I know this is down to the Digistat.

Many thanks