Installing Hive to Grenstar 18i System Boiler

T

TheAmazingJames

Joined
5 Apr 2020
Messages
1
Reaction score
0
Country
United Kingdom
I have a Worcester Bosch Greenstar 18i System ErP Condensing Boiler, a Drayton LP822 controller and Potterton PRT2 thermostat and, of course, a new Hive dual channel receiver.
vz4VnYc.jpg

FCcgP29.jpg


When I remove the Drayton from it's backplate I see what looks to be a backplate that's compatible with the Hive. It has wires already in N, L, 3, 4 and ground. Looking at the back of the Drayton, these are in the same position/order as the backplate on the Hive.
tlEmz48.jpg


As a result, I fitted the Hive onto the existing backplate. It all physically connects correctly and, once I turn the power back on, the Hive receives power, is able to pair etc and the lights for both water and the heater light up when pressed.
0D2kRtB.jpg



Whilst the boiler turns back on when I turn on the power switches, Hive is not able to get it to fire up. The switch on the zone valve actuator never moves - which is the first thing that normally happens when you turn everything on with the Drayton attached. I've tried turning the (wired) Potterton thermostat up to maximum, though cannot see how/where it's sending a signal to anything in any case. Turning it up to maximum doesn't solve the problem. The box to the right of the Hive looks like this with the cover off:
BSr4ICa.jpg

(the cable coming in from top left goes down to the floor, the first of the bottom left cables comes from Hive, the second bottom left cable comes from a power switch, the first top right cable appears to go off to the boiler, the second top right cable snakes off behind the water cylinder, whilst the black cable in the bottom right goes off to the Drayton zone valve actuator).


Does anyone know what my next steps might be?
 
BSr4ICa.jpg
The white wire I would have expected to go to the thermostat so with original thermostat not required would expect black from Hive to go to white on motorised valve, but you say it worked before and you have moved no wires, so with old thermostat at max it should have worked, I assume a Y plan so three port valve, so is so valve is:-
Green/yellow = Earth
Blue = Neutral
White = Central heating on so did go to thermostat now goes to CH NO on Hive.
Grey = Cylinder thermostat NC contact.
Orange = Boiler run this will also connect to cylinder thermostat NO contact.
So can you confirm it did work, you have not moved any wires, and it is a Y Plan, as it does not seem right that the white wire is not connected to anything.
 
When I fitted my hive I removed the old thermostat and linked the two cables together behind it the hive then powered the boiler
 
Pressing the heating button on the receiver should kick the boiler in, to check if the old thermostat is causing issues turn the temperature to max which will essentially complete the circuit and show if the receiver is correctly wired
 
Can you look and see if you have two x 2 port valves, it looks like you have an unvented cylinder and the wiring is set up for an s plan, the white wire on its own is probably the normally closed switch from a 28mm zone valve and is fine like that, also check that the old connectors on the back plate haven't been over stretched and not making contact with the new hive pins.
 
Last edited:
temp.jpg
OK it is easier if we have some reference points, first is why is that white wire with red arrow not connected to anything? B is Nest and C is supply in, so say where A, D, E and F goes. I suspect F is a motorised valve, but we can't see, you can.
 
You must log in or register to reply here.
Back
Top