Hive Dual Receiver wiring Problem

[Richard Watkins]

Hi! i am new to this forum and i hope i can explain my issue clearly?.
I am trying to wire up my new Hive Dual Receiver but cannot get Hot Water to work correctly.
First i think i am correct in thinking i have a gravity fed central heating system. Cold water tank feeding copper cylinder with three way motorized pump or perhaps a y plan system??.
My present programmer is a Seimens RWB7 which back plate looks very similar to the new Hive ,
My problem is wiring as follows Blue wire to "N" Red wire to "L" Green wire to "E" earth. i only have one wire left Black which wires to No 4 terminal which shows as heating On. There is no wire for No 3 terminal Hot Water on. There never has been but a link wire from "L" to No " terminal and everything has always worked fine.
Now when wired the same to Hive Receiver i cannot get the Hot Water to come on, the light comes on for Hot Water but the Boiler does not fire up.
Of coarse when Heating is on the hot water does heat but as soon as the thermostat cut out the boiler is not heating the hot water.
Now on reading Hive instruction for changing to Gravity fed system receiver light turns Blue as it should and when Hot Water is put on Central Heating light comes on aswell and Boiler kicks in along with pump.
I just keep thinking there should be a wire to No 3 terminal for Hot Water On.
Help Please ? Many Thanks Rich!

 

[stem]

The RWB7 is only a single channel timeswitch. The Hive is a dual channel timeswitch, they are not compatible.

Does the RWB7 control the hot water and central heating 'on' and 'off' times?

 

[Richard Watkins]

Hi! Yes the Programmer does control hot water and heating on and off times we just turn thermostat down to have water heat only. thanks for your reply Rich!

 

[stem]

The Hive has two outputs, one for heating and one for the hot water. It appears that the existing set up is that a both heating and hot water are connected to the same wire from a single channel timeswitch.

The existing programmer (aka time controller in the diagram below) should really be a dual channel with separate channels for the heating and hot water if you have a Y-Plan with a 3-Port motorised valve, as you can see from the diagram below.

So to use Hive, the system will require rewiring.

 

[Richard Watkins]

Thanks again for your technical help, So do you think if i had a Hive single channel receiver fitted it would of coarse do Heating & Hot Water on same times but if thermostat was turned down for heating , Hot Water would still be on as with old Seimens programmer ?. thanks Rich!

 

[stem]

Unfortunately, Hive doesn't work like that. The Hive provides both time and temperature control in a single unit. If you purchased a single channel Hive, because the Hive thermostat is wirelessly linked to the receiver, to have the hot water on, you would also need to have the heating actually on. So in the summer for hot water, you would need to have hot radiators too.

At the moment I guess that you have the timeswitch 'on' in the summer for the hot water, and then turn the room stat down to stop the heating coming on, with the Hive if you turn the room stat down, its only output will go off, so no hot water either.

 

[Richard Watkins]

Thank you for your help, i will need a separate signal wire to kick boiler in from the No3 terminal i wiil look at wiring this week and see if this is possible. thanks again Rich!.

 

[stem]

You will need to split the wiring currently shared by the heating and the hot water so that they are separated and not supplied from the same source.

A wire should connect terminal (3) of the Hive 'Hot water on' to the hot water cylinder thermostat's call for heat terminal, and a wire from terminal (4) 'Heating on' that goes to the white wire of the 3-port motorised valve. [You should be able to use the existing black wire for one of these, but if you use it for the hot water, you will need to disconnect if from the heating wiring. If you use it for the heating, you should disconnect it from the hot water wiring]

The Y-Plan also requires a wire from terminal (1) 'Hot water off' that goes to the Grey wire of the motorised valve.

 

[Richard Watkins]

Hi! This is what i have hope it helps ?. Cold water tank in the loft feeding boiler a presume, copper hot water cylinder with thermostat and no emersion. Three way motorized valve and room thermostat. With the room stat turned wright down to frost position and programmer turn on i get hot water only!. Turn room thermostat uo and you here pump cut in and heating gets hot. That is why wrongly i thought the Hive dual receiver would take over knowing i had turned room stat down but continue heating water. To answer the question am i am sure its a Y Plan not sure now but deffo got 3 port valve. Rich!. Thanks for not giving up on me haha.

 

[stem]

That all sounds reasonable. 3-port valve = Y-plan.

I deleted some of my previous post before you replied that made reference to 'hot water off' missing from the existing timeswitch. Which. after I posted it I realised with your current set up (heating & hot water 'on' and 'off' together) will only presently come from the hot water cylinder thermostat, so it's not relevant to the current set up. However, once you separate the heating and hot water you will need a 'hot water off' from the Hive. So, my comments about terminals (1) (3) and (4) above are still relevant.

 

[Richard Watkins]

Thanks again its good to have advise from you i will as soon as i can trace my wiring making note where they feed and try to separate feeds for HW & CH . Rich!