Another Hive Wiring Issue...Gravity Fed Dandoss 103 to Dual channel Hive

if I disconnect the thermostat downstairs will I be able to pull on the wire to get it out that way?
Sorry but I don't know. It depends upon how the cable is installed in your property, if it is clipped to the surface, buried in the plaster, run between floors etc. You might not be able to get it out along its entire length, but the important thing is to make sure any redundant cables are made safe by being completely disconnected and the loose ends not left hanging around where they could inadvertently come into contact with live wires.

The house was built in 1992, I was surprised it didn't have a combi but a previous plumber said it may be because it has 3 bathrooms and 14 radiators and this system was best to deal with that. It all works fine so I won't replace until the boiler breaks.
I wouldn't have expected to find a combi boiler, as stored hot water would be required for a home with 3 bathrooms, but for a property built in 1992 to have a gravity hot water system is very unusual. I would have expected to find a fully pumped system with motorised valve (or valves) to control the water flow from the boiler so that the pump also supplies the hot water cylinder (as per the diagram below) instead of it being heated by gravity circulation. Which is why I wanted you to check to be absolutely sure. If you compare the diagram below with the previous diagram sent you will see the difference between the two types of system. The wiring diagram I sent for installing the Hive is for a system with gravity fed hot water, it is not applicable to a fully pumped system.

FULLY PUMPED SYSTEM
fully p.gif


I've just gone out and bought a multimeter, which settings do I need to use to trace which wire is which?
That's not really something I can explain over a forum like this. But there are plenty of tutorials on line that will show you how to use it. The easiest and safest way would be to disconnect everything and then test each cable using the resistance settings to check the continuity of the wires in each cable allowing you to identify which is which. Check using the voltage function first to make sure that the cable you are testing is safe to work on.

Drawing1 Model (1).jpg

To be sure, repeat the test with the far end disconnected and the reading will show a very high resistance.

When you say strip it all out, how would I start that as obviously the wires are in the wall and I wouldn't be able to go down further unless I made a hole in the wall?
Just make sure that they are completely disconnected and remove them where you can, so they aren't likely to pose a danger by coming into contact with something they shouldn't.
 
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Stem's cable testing diagram is very good, well done,

I would suggest that after finding the low resistance reading the two conductors are then disconnected from each other and another test, this time for high (infinite ) resistance is made to confirm it is the right cable.
 
I would suggest that after finding the low resistance reading the two conductors are then disconnected from each other and another test, this time for high (infinite ) resistance is made to confirm it is the right cable.

Funny that you say that, I thought exactly the same after rereading my post and had just amended it as you replied. (y)
 
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make sure any redundant cables are made safe by being completely disconnected and the loose ends not left hanging around where they could inadvertently come into contact with live wires.

I understand this now, I need to check continuity of the wires using the resistance settings (buzzer or 200) then disconnect and enclose in a plastic connector?

I would have expected to find a fully pumped system with motorised valve (or valves) to control the water flow from the boiler so that the pump also supplies the hot water cylinder (as per the diagram below) instead of it being heated by gravity circulation. Which is why I wanted you to check to be absolutely sure.

How can I check if it is fully pumped? I have had a look at pictures online but cannot find anything to refer to. There is something connected to the hot water cylinder in the airing cupboard I can take a picture if it helps.

The easiest and safest way would be to disconnect everything and then test each cable using the resistance settings to check the continuity of the wires in each cable allowing you to identify which is which.

I have spent the last couple of hours researching this subject as well as watching videos and I am now comfortable using my multimeter to check continuity. Easy when you know how! And yes your diagram is spot on.

Now I just need to find out where the other ends of the wires are for the pump and boiler. Is there an obvious place to look?

Cheers
 
Do you have to be so rude, I'm asking a question I don't know the answer to. It may sound simple to some people but I like to make sure I know exactly what I'm doing before I attempt it.

If you don't have anything constructive to say then please don't bother replying to my thread.
 
This is my hot water cylinder :

20190612_062046.jpg

20190612_062041.jpg


I take it that's the pump? So is my system fully pumped? If so would the wiring be different to connect?
 
I understand this now, I need to check continuity of the wires using the resistance settings (buzzer or 200) then disconnect and enclose in a plastic connector?
Yes, the connector is just there to join the wires together to make a loop whilst you make the continuity check.

How can I check if it is fully pumped? I have had a look at pictures online but cannot find anything to refer to. There is something connected to the hot water cylinder in the airing cupboard I can take a picture if it helps.

That looks like fully pumped to me, the pipe from the pump supplies the hot water cylinder, so yes, the wiring will be totally different, meaning it's 'back to the drawing board' I'm afraid.

At the moment, for the hot water to be heated, the pump needs to operate, which means that the room thermostat can't presently be controlling the pump, otherwise you wouldn't get any hot water when the radiators weren't on. So the first question is if the room thermostat isn't wired to to pump, what is it wired to? I would expect the room thermostat to be controlling a motorised valve. Something like this.


I think you may be best getting a professional in on this one. Without having a knowledge of all of the system components you have, how they are connected to each other and what is attached to each of the existing wires it's going to be difficult to workout over a forum.
 
The heating comes on 1 hour in the morning and 1 hour in the evening, it is impossible to stop this from happening because of the way you change the time on the time switch.

When the heating is on you can hear the hot water cylinder running in the airing cupboard. If I turn the thermostat downstairs to 0 it turns the heating off and the hot water cylinder stops running.

Seemed so close but thanks for your help and diagrams. I've definitely learnt a few things attempting this which is always a good thing. I'm going to research more on the multimeter as I find it interesting how it works.
 
If you are saying that when the room thermostat goes off, that the hot water goes off too, that is completely wrong and the whole thing is a mess and not suitable for control with Hive, or any other dual channel programmer for that matter.

The plumbing system needs a single Three-Port Motorised valve (making it what is known as a Y-Plan) or 2, Two-Port Motorised valves (making it what is known as an S-Plan) and then all of the existing wiring will go, and it will be rewired from scratch.

If you want any more information there's loads on the web if you search 'Y-Plan' or 'S-Plan'.
 
The mechanical timer I have is basically on, off or on timer, there is no way of turning hot water on or off separately so when it comes on it heats the water up as well as turning all the radiators on.

If I turn the dial on this all the way off to 0 :

20190609_164809.jpg


Then it turns the heating off. I can hear the water up separately using the switch for the immersion heater in the cylinder but that is a faff and probably costing more to heat the water.
 
your system is a total bosh, in the pic with your pump above it is a gate valve (red handled valve) looks as if that is a manual way to shut the heating off and leaving the HW only running, as @stem says a hive is no good for your set up without adding additional controls
 
Started reading this post but gave up after a few replies. There are times when one has to realise there are are guys with knowledge, guys who wish to acquire knowledge, guys who think they will acquire knowledge and finally should get someone with knowledge:whistle:

Stem clearly knows what wire goes where
There are heating engineers who I would not get to wire a plug top
There are electricians who have no knowledge ( same with heating so called engineers) of control wiring.
Hive and end users attempting to convert their controls to these smart stats is littering these pages like discarded burger wrappers in a 24 hour burger joint car park :LOL:

Good luck OP, was thinking of offering my idea on how system could be converted to work but reading It is hive, cannot be a7sed. BTW have converted many such systems to give control of heating 24/7 (hot water comes on while heating is on ). Hot water on its own would be temperature controlled though not during heating demand.

There is a type of installation where the cylinder is hooked up same as a radiator and the pump runs during ch and hw demand, no separation. Without plumbing alteration no hope of splitting the system
 
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Just to add to this, I spoke to numerous plumbers who couldn't do it and directed me to various electricians who couldn't/ wouldn't do it.

I've decided to give up on the Hive altogether and cut my losses.

I would still like to separate my heating and hot water. Do I now need a 3 port valve to enable me to do this?

Also is it possible to replace my mechanical Danfoss 103 to a similar electrical unit?

Thanks for everyone's help with previous replies.
 

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