Heating controller and thermostat change

[James94]

Hi,

not sure how difficult this would be for me but my manna and grandad are having trouble with controlling the heating and hot water. I have been on the phone to hive and they want £278 including installation and i’m not sure if I could diy it and save them some money.

the issue is if there is any issues with my diy install and they are without heating and water I’ll. e in trouble as my grandad has cancer and feels the cold badly.

I have a few pics of there system which is a conventional one with tanks in loft for hot water and boiler in kitchen cupboard with thermostat and controller.

 

Regards. James

[Temp]

What problem are they having? Is the existing controller faulty or are they just having difficulty working it?  

 

That thermostat is pretty crude. A small turn of the dial can change the temperature several degrees. Is it possible they are just over controlling it?.. too cold.. turn it up.. too hot.. turn it down repeat?

 

 

Edited April 11, 2023 by Temp

[James94]

@Temp

The issue is with the controller, I don’t think they use the thermostat at all. The controller works when on manual for hot water and heating, but they have to turn it off at the boiler as I has a mind of its own and switch’s things on and off, so not sure what’s going on with it. I was hoping to maybe just remove and replace with a hive system.

[Temp]

Im not very familiar with the Hive controller but isn't it App based?  Are they young enough to cope with that? Won't find it too confusing? 

 

Youtube has guides on how to install hive but it's not necessarily straight forward. 

 

 

 

 

 

[Temp]

There are plenty of conventional programmers available from the likes of Honeywell they might find more familiar?

[James94]

@Temp

Very good video but will need to watch it a few more times. Yes it is app based but it has a portable control stat and yes they are a bit passed it but I think once it’s set up they should be ok, maybe get the odd phone call or two.

I’m not sure about just replacing with a conventional controller, with the hive they won’t have to keep going into cupboard to switch it on and off, will be able to do it from the comfort of the  sofa😛 

[SimonD]

The Hive will go straight onto the black wall plate you've shown in one of your photos. You then need to either bridge the existing thermostat behind the stat - use a simple wago connector - or rewire elsewhere if preferred.

 

However, if you're experiencing strange behaviour it's worth getting someone in to test the system as there can sometimes be other issues causing the boiler to turn on or off when it shouldn't - for example, a faulty motorised valve can sometimes cause a permanent live to the boiler.

 

Process is install the hub > Install the receiver > Add the Thermostat > Complete online setup through the app.

 

Hive customer support is very good and responsive to setup queries - they have a phone number and answer it too!

 

HTH.

Edited April 11, 2023 by SimonD

[Temp]

+1  if that black backplate still used? 

 

It's got wood to the left so its not the one behind the controller? or the thermostat? 

[SimonD]

6 minutes ago, Temp said:

It's got wood to the left so its not the one behind the controller? or the thermostat? 

 I just assumed it was the same slightly yellowed conduit in the close up shot, but maybe not?

[James94]

@SimonD@temp

I’m hoping it’s just a controller issue and going to switch controller first fingers crossed.

You say the hive controller will fit straight onto back plate, so all wiring is in correct positions for new controller?

also not to sure what you mean about bridging the thermostat, can I just remove it?

 

 

[James94]

17 minutes ago, Temp said:

+1  if that black backplate still used? 

 

It's got wood to the left so its not the one behind the controller? or the thermostat? 

Sorry but I’m not sure what you mean

[dpmiller]

it's the same one, just upside down I think

[SimonD]

27 minutes ago, James94 said:

@SimonD@temp

I’m hoping it’s just a controller issue and going to switch controller first fingers crossed.

You say the hive controller will fit straight onto back plate, so all wiring is in correct positions for new controller?

also not to sure what you mean about bridging the thermostat, can I just remove it?

 

 

 

Yes, the hive receiver will just fit straight onto the existing backplate. The wiring is in the correct place with 3 for hot water and 4 for heating and presumably the initial installation put these round the right way - I obviously can't warrant that as I've not tested them! But even if after you installed the hive you found that the hot water went on when it was supposed to heat the house or it heated the house when it was supposed to heat the water, you could swap those wires around. No big deal.

 

Your existing thermostat is basically a relay switch, it is either on or off. If it's off, then there's no voltage through that circuit. With a Hive, it controls that switching instead of the thermostat so it needs a permanent live. The easiest way to do this is by connecting the two wires connected to the thermostat and then replacing the thermostat with a blanking plate. Otherwise you need to rewire the thermostat switched live in your wiring centre which is next to the hot water cylinder - this is more complicated and by the sounds of your questions, not something you really want to be doing.

[James94]

Thanks for all your help,

If i attempt this fitting of hive heating and hot water I think I’m going to remove the thermostat, but instead of bridging the  wires I think I’m going to  trace them back to the wiring centre in the loft and join them up in there. Hopefully the wiring should be like the video shows. It looks simple enough.

Regards. James

[James94]

@SimonD@temp

Just removed the thermostat casing and taken a picture, if I choose not to or struggle tracing wires back to wiring centre. Is it just the case of a wago the live and yellow together that’s in three?

what do I need to do with neutral and earth wires?

Regards. James

[James94]

Here’s a picture of the wiring centre, not sure if this would help anyone in giving me advice on where to bridge.

Regards. James

[ProDave]

You need to actually check the system operation before adopting the "fault finding by substitution" technique before you waste any money (replace the controller with the hive and find it still does not work)

 

The existing programmer should work.  It should have a light to show when heating is on and when hot water is on.  Do those lights turn on and off at the correct times as expected?  if not the programmer is probably faulty.

 

If the lights on the programmer operate as they should but the boiler is switching on and off at eratic times not related to what the programmer is doing, then it will almost certainly be one of the motorised valves in the cupboard with the tank has failed.  they look like Honeywell so unless they have seized it is usally the actuator head that fails and they can be replaced without needing a plumber.

 

The existing system should just work heating and hot water on and off when they set it and temperature what they set it, with no continual input from the user.

[TonyT]

Personally I think the Drayton range of 2 channel controllers are the best and easiest to understand, have the 1 hour boost button and don’t need a degree in engineering to program.

 

in the situation you describe best to just prove functionality of the existing and if required swap like for like with no wiring modifications required.

[James94]

@ProDave

At the moment they are having to turn off boiler on the front boiler off switch to stop it from firing up on its own.

taken a quick video to show the erratic behaviour.

 

[ProDave]

Is that you pushing buttons, or is the right hand selector flag moving upwards of it's own accord?

 

The heating and hot water lights on the programmer appear to be both off, yet you say the boiler is firing unless you turn it off at the boiler.

 

I suspect you have multiple faults, what is your level of expertise around electrical circuits, fault finding with a multi meter?

[James94]

@ProDave

No not pushing any buttons, they move on their own and the boiler will fire up if it stops on something,In the video both light are on but might look like there off.

I do own a multi meter and have done bits with it but usually after watching YouTube videos.

[ProDave]

Turn the power off, unclip the existing programmer from it's back plate, and turn the power back on.  Be careful live terminals are exposed on that backplate so don't touch and don't leave it unattended with power on.

 

Like that the boiiler should not fire up.

 

Then manually open each of the motorised valves and see if the pump starts and the boiler fires as you open each one.

 

Only change to the hive if you really want to have it controlled by an app and that is really what you want, otherwise start with a new perfectly ordinary 2 channel central heating programmer.

[James94]

@ProDave

I’ve followed what you have said but I couldn’t isolate controller as I don’t know where it switches off, no spurs anywhere and doesn’t turn of in consumer unit either.

I went upstairs into loft and switched water valve on but it didn’t seem to do anything, not sure I I was supposed to hear owt at boiler. Then I did same with heating valve and boiler fired up and a pump kicked in next to valve see pictures.

was I supposed to of had different things happen.

Regards. James

 

[TonyT]

What about the spur around the corner from your wiring centre that has the white flex 

[ProDave]

Well something will turn it off at the consumer unit, if not it's own circuit then probably one of the socket circuits. But agree that surface mount box just round the corner from the wiring centre looks prime candidate.

 

Interesting it has 2 different makes of motorised valve.  That bottom one is a re badged I think Danfoss valve.  I hate those, they are pretty poorly built but the think I hate is there have been several design changes and newer heads won't fit older valve bodies and some versions you can't even detach the valve head from the body so have to change the whole thing, preferably for a better make like the Honeywell one in the picture above.