Hi,
I bought a Nest unit recently having checked for compatibility with the Nest survey on their site. Unfortunately, their survey did not take into account W Plan heating which is not compatible but which they indicated would be okay. Having looked into the situation for the last couple of days (and discovered that there is some blackening/charring beginning to occur inside the case of my ancient Randall 3022 controller so it definitely must go) I think the best solution is to swap the system to Y Plan and install the nest.
I have ordered a straight swap Honeywell mid position, 3 port valve and a Salus Wiring Centre. The valve "should" be straightforward to change and I have spent some considerable time studying up on the wiring (the way I found this great place) and feel capable of rewiring the system into the wiring centre.
The issue I have is the wiring in the boiler. I have an old British Gas RD1 boiler and (surprise surprise) it doesn't follow the modern standard wiring diagrams. The pump is not wired into the boiler direct but is wired into the controller in the upstairs airing cupboard. This is as per the instructions in the boiler manual so I am assuming I can just swap this over to being wired into the wiring centre in the Y Plan setup (again as per the manual). The thing that is vexing me is the switched live wiring.
Currently the set up seems to be that the live feed comes down to the boiler from the controller unit and is wired into L N E terminals then a permanent connection goes from the live terminal to the EC1 terminal which is supposed to be used for the switched live. This must work due to the mains supply itself being used as the switch via the wiring in the current control unit. This is not to modern wiring diagrams or the y plan set up in the boiler manual but can I just swap this over as is or should I change the wiring putting a separate switched live in from the wiring centre? And if I do that is it okay to leave the mains supply to the boiler coming from the wiring centre?
Thanks for any help and sorry for the mammoth post but I am trying to keep everything straight in my tiny brain as much as anything else!
Edit: N.B. My tiny brain also decided to put the wrong title on my first post here. D'oh - it is Y Plan that I am trying to convert to. Clearly I have plan fug...... fixed - Mod
I bought a Nest unit recently having checked for compatibility with the Nest survey on their site. Unfortunately, their survey did not take into account W Plan heating which is not compatible but which they indicated would be okay. Having looked into the situation for the last couple of days (and discovered that there is some blackening/charring beginning to occur inside the case of my ancient Randall 3022 controller so it definitely must go) I think the best solution is to swap the system to Y Plan and install the nest.
I have ordered a straight swap Honeywell mid position, 3 port valve and a Salus Wiring Centre. The valve "should" be straightforward to change and I have spent some considerable time studying up on the wiring (the way I found this great place) and feel capable of rewiring the system into the wiring centre.
The issue I have is the wiring in the boiler. I have an old British Gas RD1 boiler and (surprise surprise) it doesn't follow the modern standard wiring diagrams. The pump is not wired into the boiler direct but is wired into the controller in the upstairs airing cupboard. This is as per the instructions in the boiler manual so I am assuming I can just swap this over to being wired into the wiring centre in the Y Plan setup (again as per the manual). The thing that is vexing me is the switched live wiring.
Currently the set up seems to be that the live feed comes down to the boiler from the controller unit and is wired into L N E terminals then a permanent connection goes from the live terminal to the EC1 terminal which is supposed to be used for the switched live. This must work due to the mains supply itself being used as the switch via the wiring in the current control unit. This is not to modern wiring diagrams or the y plan set up in the boiler manual but can I just swap this over as is or should I change the wiring putting a separate switched live in from the wiring centre? And if I do that is it okay to leave the mains supply to the boiler coming from the wiring centre?
Thanks for any help and sorry for the mammoth post but I am trying to keep everything straight in my tiny brain as much as anything else!
Edit: N.B. My tiny brain also decided to put the wrong title on my first post here. D'oh - it is Y Plan that I am trying to convert to. Clearly I have plan fug...... fixed - Mod
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