Stuck on Wiser 2 channel wiring

[Jaguartvr]

I am hoping someone can help me with the Wiser 2 channel hub wiring.
I have a conventional boiler pumped central heating and hot water. Potterton boiler.
I currently have a Danfoss WC4b wiring centre and Danfoss thermostat, all working fine. I have tried wiring the new Wiser hub but without success.

Current wiring
From the Danfoss hub
Terminal 8 (green/yellow) goes to terminal 1 on the hub
Terminal 9 (blue) goes to terminal 4 on the hub
Terminal 10 (brown) goes to terminal 3 on the hub

Can anyone tell me what the correct wiring should be for this?

Many thanks in advance

 

[CBW]

Exactly the same, and you might even be able to use the existing backplate. You need to ensure that the green/yellow cpc connected to terminal 1 is sleeved or apply some brown insulation tape to show its being used as a live wire though. It shouldn’t have been used, especially since there‘s already an earth wire.

 

[Jaguartvr]

Thanks for the prompt reply

That is exactly what I tried first of all but it doesn't work.

I then tried

N blue
L brown
1 brown > term 10 HW
2 not used
3blue>term 10 CH
4 not used

and still doesn't work

 

[RandomGrinch]

and still doesn't work

What, exactly doesn't work?

Is there a power light on the receiver?
Do the buttons for heating and hot water not work, or is the thermostat not communicating with the receiver.

As @CBW says above, the wiser could probably sit on that back plate and work. The wiring should be identical.

Are you sure you have the 2 channel model?

 

[Jaguartvr]

I definitely have the wiser 2 chanel.

The hub is illuminated and all set up with my phone. If I turn the hot water, central heating or both on then the hub illuminates but won't fire the boiler.
The current thermostat is turned to max, I was going to remove it once the system was working.

 

[ian1182]

Have you made any wiring changes at the WC4B ?

Can you confirm your system is Y-Plan, there should be a 3-port valve near the pump. For example a Drayton MA1

As CBW indicated you could have probably just placed the Wiser hub on the old backplate without any changes at all.

Can you post a picture of your WiserHub backplate wiring as I believe there should be a connection going to #4.

If not already done you should carefully differentiate the various brown, blue & green/yellow cores. Plus I'd recommend you tidy up the loose strands to ensure nothing touches where it should not.

you said...
N blue
L brown
1 brown > term 10 HW
2 not used
3blue>term 10 CH
4 not used

I think
N blue
L brown
1 (green/yellow) -> term 8 (HW off) <<== Add some sleeving
3 (brown) -> term 10 (HW on)
4 (blue) -> term 9 (Heating on)

BUT... before you change anything, some pictures please.

 

[RandomGrinch]

What thermostat and programmer do you have?
Are you installing the Wiser in the same place as the old programmer?

 

[Jaguartvr]

I have made no changes to the Danfoss WC4b.
The backplate from the original Danfoss FP715 is identical to the new wiser backplate so I haven't changed it.
The connections are as in picture 2, terminal 4 is used

Thermostat currently on the system is an RMT 30 turned up to max. I was going to remove it once the system was working

 

[RandomGrinch]

The connections are as in picture 2, terminal 4 is used

So does it work, if you put the FP715, back on the backplate?

 

[ian1182]

I have made no changes to the Danfoss WC4b.
The backplate from the original Danfoss FP715 is identical to the new wiser backplate so I haven't changed it.
The connections are as in picture 2, terminal 4 is used

Thermostat currently on the system is an RMT 30 turned up to max. I was going to remove it once the system wa

so you have undone the changes made in your 1:59 reply?

 

[Jaguartvr]

If I put the FP715 back it all works perfectly. (as I have had to do)

 

[RandomGrinch]

If I put the FP715 back it all works perfectly. (as I have had to do)

There is the possibility that the new Wiser may be faulty, or has poor connections to the old backplate (although visually it looks ok from the photo).
Have you got any test equipment (multimeter) to confirm?

 

[stem]

A bit obvious I know, but are the hot water and heating actually calling for heat? If the hot water cylinder is already full of hot water then that won't switch the boiler on, and if the room where the Wiser thermostat is located is already the same temperature or warmer than its set temperature that won't switch the boiler on either.

Swapping back to to the FP715 with the old thermostat on max, would of course start the boiler.

 

[Jaguartvr]

If I fit the original FP715 programmer it all fires up, hot water and heat. If I then swap to the wiser it lights up but won't fire the boiler for heat or water, swap straight back and it works again.
I was suspecting I had made a mistake with the wiring but it seems not from the advice on here.
I can only presume the wiser is faulty and not calling for the hot water or heating.

I have undone the changes made in my 1.59 reply and have gone back to my first picture which I believe is correct.

 

[ian1182]

If you have a multimeter you can check if 240V appears on the WC4B terminals...

T8 when NOT calling for hot water (from backplate T1)
T10 when calling for HW (from backplate T3)

T9 when calling for central heating (from backplate T4)

You can also listen out for a click when pressing the "Hot Water" or "Central Heating" buttons on the front of the hub indicating the solenoid is closing.

If you feel confident, you can also check the Wiser Hub in isolation by running a regular power lead connected to a plug with a 3A fuse. Just connect that to the L & N terminals on the backplate. Mount the Wiser Hub on the backplate & then using a multimeter check for 240V on T1, T3 & T4 as appropriate as you turn on HW or CH. Naturally enough be very careful in doing so.