Our current heating system has a Potterton EP2002 controller and Potterton Prima 60F boiler. I have bought a Wiser multi-zone kit 2 plus a number of Wiser TRVs in order to have easier and more fine-grained control.
Replacing the EP2002 with the Wiser hub simply involved swapping the wallplate and connecting the cables from L/N and 3/4 into the same connections on the new plate. (There is also a jumper wire from L to 5 in the EP2002, but looking at the diagrams, and the lack of a terminal 5 in the Wiser plate, I think I can just leave this out.)
Nearly everything works fine. When I switch on hot water, the diverter valve lights up DHW, the pump runs, and the boiler fires. But when I switch on central heating, the diverter value lights up CH, but the pump doesn't run and the boiler doesn't fire.
The existing wired room thermostat, for the purposes of testing, is just set to max so that it doesn't interfere.
Replacing the EP2002 makes everything work again. (So at least we're not cold while this gets sorted...)
There's one strange thing I've noticed which may be relevant. On our current (EP2002) system, when I switch the CH on, it automatically also switches on the hot water. That's a physical thing that you can see when you move the switch to 'Once' or whatever, and it happens too if I hit EXT or ADV - if the CH is switched on, the DHW comes on with it. It seems (from my layman's perspective) that this is what's missing with the Wiser setup.
I had hoped that it would be an easy drop-in replacement ... but it seems not. What can I do?
Replacing the EP2002 with the Wiser hub simply involved swapping the wallplate and connecting the cables from L/N and 3/4 into the same connections on the new plate. (There is also a jumper wire from L to 5 in the EP2002, but looking at the diagrams, and the lack of a terminal 5 in the Wiser plate, I think I can just leave this out.)
Nearly everything works fine. When I switch on hot water, the diverter valve lights up DHW, the pump runs, and the boiler fires. But when I switch on central heating, the diverter value lights up CH, but the pump doesn't run and the boiler doesn't fire.
The existing wired room thermostat, for the purposes of testing, is just set to max so that it doesn't interfere.
Replacing the EP2002 makes everything work again. (So at least we're not cold while this gets sorted...)
There's one strange thing I've noticed which may be relevant. On our current (EP2002) system, when I switch the CH on, it automatically also switches on the hot water. That's a physical thing that you can see when you move the switch to 'Once' or whatever, and it happens too if I hit EXT or ADV - if the CH is switched on, the DHW comes on with it. It seems (from my layman's perspective) that this is what's missing with the Wiser setup.
I had hoped that it would be an easy drop-in replacement ... but it seems not. What can I do?
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