Replace Siemens RWB9 programmers with Drayton Wiser 3 Channel.

[DiyAnothrDay]

Hey Guys,

I currently have dual zone heating in the house with a system boiler and tank. A thermostat upstairs and one downstairs. There are 2 Siemens programmers near the boiler, one for heating downstairs and water, and the other for upstairs.

I want to replace the existing system with a smart Drayton wiser 3 channel Kit. Normally they seem to say just remove the old programmer and put the hub there, but in this case I have 2 programmers. How would the Drayton Hub be installed? I have posted a picture for reference to current programmers.

Thanks for the help.

 

[CBW]

After carrying out safe isolation, you would need to cut the cable back so they're of equal length and you'd need to put the relevant wires in the relevant terminals, but you would also need to remove a permanent live and permanent neutral unless they can be safely isolated (I'm unsure of this as not an electrician).

 

[DiyAnothrDay]

Hey, thanks for the reply. I had another question, so I already had 1 nest thermostat from my old house, if I buy another, would it be as easy as replacing the 2 programmers with the 2 heatlinks and being good to go, or would that not work and the heatlinks need to directly wired aswell in the connection box? Trying to decide between another Nest and have 2 for the 2 zones, or just switch to the Drayton and wire everything into one box. Thanks again.

 

[CBW]

Yep, you can replace the 2 programmers with 2 heat links, which would negate the need for cutting back the cable and terminating the live and neutral as they’d be needed for the heat link too. Unless you plan on using the usb cable then you’d need to run separate cable for the thermostats to be powered from the heatlinks.

 

[DiyAnothrDay]

Yep, you can replace the 2 programmers with 2 heat links, which would negate the need for cutting back the cable and terminating the live and neutral as they’d be needed for the heat link too. Unless you plan on using the usb cable then you’d need to run separate cable for the thermostats to be powered from the heatlinks.

Thanks again for the information Chris. I have decided to go down the drayton route to try a different system. As for installation, not sure how I will manage that side given the wiring.

 

[CBW]

. As for installation, not sure how I will manage that side given the wiring.

Well, if you get stuck ask on here. Failing that, maybe get someone in?

 

[DiyAnothrDay]

Well, if you get stuck ask on here. Failing that, maybe get someone in?

I have considered getting someone in, but it seems the availability is minimal and whether to contact a electrician or heating person, as well as if it is doable myself, I would prefer to if it is not going to be dangerous or dodgy to do the wiring.

I have attached additional pictures showing the wiring underneath the programmers. The one programmer being the upstairs heating only. Wiring of bottom plate is for downstairs heating and water, while other is for upstairs heating.

 

[CBW]

Either trade would be fine, as long as they’re competent. If you’re to do this yourself, ensure you can safely isolate, cut back the left hand one (looking at it) to match the level of the other, then it would be transfer the wires over, minus one set of live and neutral, and no link.

 

[ericmark]

It will likely take some working out, if I was doing it likely I would fit a junction box (some times called a wiring centre) at end of trunking to bring both together and give some room to work in with the Drayton unit either to side or under it. This is how I did it, as Nest has very little room inside.

You need to plan it out on paper, you are unlikely to remember it all, and if you come to change something latter good to be able to look back this is mine my mistake was I did not put a version on them, and now can't remember which one I used.

I realised my plumbing skills were not good, so I got a plumber who in turn got a heating guy, and both said not sure how to wire it, since I did I was not worried. But may find either the electrician or the plumber if they can't do it will tell you who can.

 

[DiyAnothrDay]

Thanks Eric, I will have a closer look at your diagram as well, and the addition of a wiring centre sounds like a good idea. I did contact a few electricians, about 3 so far, all of whom say they don't mess with thermostats, so not sure why the reluctance given their expertise should make this job relatively straight forward for them.

 

[ericmark]

In general the heating system is about the most complex domestic install. Commercial it's easy peasy we have far more complex system, with e-bus linking and PLC control, I did consider using a PLC however the problem is as I get older I may not be able to DIY, and although my son also works with PLC's he lives 50 miles away, so I wanted something as normal as possible.

I would not bother studying my system, it is C Plan and designed to work with my oil boiler, it was just how I laid it out on paper so I could return later and know what did what. Yours is likely a lot simpler, what messed mine up was two pumps.