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Upgrading EPH Programmer to Drayton Wiser 2-Channel

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Hi,

I'm hoping to switch my old Electronic Programmer from an EPH R27 over to a Drayton Wiser 2-Channel Kit.
I thought it would just be a case or removing the old EPH Programmer and popping on the new Drayton Smart Hub.

But it seems things are backwards in terms of functionality when I do.
Turning on the Hot Water on the Hub starts the HW + CH
Turning on the Central Heating on the Hub starts the HW (no CH)

My existing Electronic Programmer has two Zone buttons on it. Zone 1 and Zone 2.
Eph_Programmer.jpg


They weren't specifically labelled as HW and CH on the buttons or LCD display, but when I removed it and looked at the back of the programmer they are for the pins that connect to the Backplate
Eph_Backside.jpg

When Zone 1 is powered on, it runs the CH (+HW)
When Zone 2 is powered on by itself, it runs the HW only
When both Zone buttons are activated, it is the same as just running Zone 1 as it does both HW+CH anyway

It seems like maybe that the HW should actually be Zone 1 and CH Zone 2

I'm not sure if my Electrician wired up the programmer incorrectly when he fit it.
I switched from an ancient Firebird Super-Q 5-90 Boiler that had two switches. HW and HW+CH and replaced with a new Warmflow Condensing Boiler.

When the electronic programmer went in, the Electrician labelled Zone 1 as HW and Zone 2 as CH but that was never the case.
They were actually backwards when the buttons were activated. I just put it down to him labelling them incorrectly but now I suspect that maybe he wired 3 (HW) into 4 (CH), and 4 (CH) into 3 (HW)
The Backplate is wired into a fused switch also.
Backplate_Wiring.jpg


Would it just be a case of me switching the wires going into 3 and 4 respectively?
Taking the 2 grey wires in #4 and putting them in #3, then putting the brown wire in #3 into #4

Or is it best just to get an electrician back?

Thanks in advance.
 
Wow that's a lot of information. I'm slightly confused, are you describing the way the EPH works is backwards or when you have fitted the Wiser?
 
Wow that's a lot of information. I'm slightly confused, are you describing the way the EPH works is backwards or when you have fitted the Wiser?
Hi

So the Wiser seems to work backwards when it's attached to the existing Backplate.

And I'm not sure if it's doing that because the backplate that was fitted with the EPH programmer was wired backwards to begin with. As it just had generically named buttons called Zone 1 and Zone 2.
 
Would it just be a case of me switching the wires going into 3 and 4 respectively?
Taking the 2 grey wires in #4 and putting them in #3, then putting the brown wire in #3 into #4
I would try this first then and report back please
 
I would try this first then and report back please
That seems to have done the trick.
The backplate must have been wired with points 3 and 4 in reverse.

The Drayton Wiser app turns the CH on now when it should.

My next issue is that the Wiser TRV ring nuts don't fit my current manual TRVs so I'm going to have to search for an adapter for those now, but that's a separate issue.

Thanks again.
 
Sorry I should have said non-smart TRV's
They are pretty old, the name on them is Orkli
They don't seem to be 30mm x 1.5
They have a slightly smaller diameter. Maybe 28 or 29mm

I'll see if I can find adapters for them online or else it might be a job for a plumber to replace them.

The main thing is the Drayton seems to be going ok now.
 

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