Hive with Drayton LP522, LWC1 connection box & Digistat SCR

[munties]

Hello,

I'm after some advice regarding what may be wrong with either the wiring or the Hive system.

Like many people I bought a Hive Active Home on Amazon Prime day.

One of the reasons I went for Hive was that is should have been a simple case of remove the old programmer & clip on the new Hive.

I disconnected the old wireless Digistat SCR, linked the wires at 2 & 3 on the LWC1. Set everything up & started to test it all worked. Hot water not a problem, heating however causes both green lights on the receiver for hot water and heating to come on & the Y valve to go to mid point.

I checked that the hot water wasn't set to be on & looked at the wiring several times & could see what the issue was. I started to feed another wire to the receiver back plate for connector 2 (heating off) in case it needed it to stop a back feed. But there was no point to connect it to in the LWC1, several posts I found online claim I don't need it for my system. The next thing I did was remove wire from connection 3 from hot water off at the LWC1 but that made no difference.

I'm getting stumped now & looking for more advice if someone can help me please. Sorry if I waffled on a bit but hopefully I've given enough info. Here are some pictures of the system to hopefully help someone find the issue.

Thanks.

https://ibb.co/caXjxv
https://ibb.co/gE5hja
https://ibb.co/jQWoPa

 

[stem]

It would appear to me from your description that you may indeed missing the 'hot water not required' signal.

The three port valve needs this to fully wind across and close off the hot water port. This signal comes from two places. HW off at the programmer and also from the HW satisfied (up to temperature) from the hot water cylinder thermostat (HTS terminal 2). Both are clearly shown in the diagram you have posted. If you follow the links through you will see both are connected to the grey wire at the motorised valve.

Check that this is the case with your installation. Be careful though, not all installers stick to the terminal numbers as per the diagram you posted, so may have use different terminals. (You may be fortunate and have one that does follow convention) but just in case not, trace where the wires actually go instead.

In any event, the 'hot water not required' wire would have been necessary to operate the system correctly before you changed the programmer, the Drayton MA1 three port valve needs this connection to work properly.

 

[munties]

Thanks Stem, I was hoping you would look at this & reply for me.

I've had a multimeter checking where there is and isn't power today. With only the call for boost on Central Heating (CH) I get the green blinking light on the receiver & as long as the temp is set high enough on the Hive control unit I get both Hot Water (HW) & CH light up.

I get 240v at connector 9 on the LWC1 coming from the receiver for CH call going to connection 3 on the LWC1. Which was the room stat & is now linked from 3 to 2 then going to 4 the Light Grey/White wire to the MA1.

There is also 106v at connection 8 (HW off from receiver) on the LWC1 which I found was coming from the dark grey at 7 from the MA1 (linked into Cyl Stat as well). Then there is 240v at connection 10 coming from the hive receiver which is the call for HW.

It's this last one that I think is the issue as there is no call for HW from the main Hive unit or on any app etc. I have traced the from connection 10 on the LWC1 to connector 3 on the base plate for the Hive receiver & it is the HW on signal. As it all should be according to the wiring diagrams.

If I disconnect this wire on the LWC1 & request CH I still get both lights on the receiver & 240v from the lose wire at the LWC1. Unless you can think of anything different it looks to be a faulty receiver & I'll either need to contact Amazon or the Hive help line to see what they suggest.

Thanks for reading through my mini essay but as you can hopefully see, I've checked out as much as I could & confirmed all wires go where they should do.

Thanks for your help.

 

[munties]

Sorry I also forgot to say that with no calls for HW or CH there is 240v at connector 8 on the LWC1 for HW off.

 

[Johnmdc]

It sounds like your receiver is set to gravity mode if the HW light comes on as well when only the CH is meant to.