Hive Installation

[Hawkeye65]

Hi

I am looking at possibly upgrading our existing system with Hive, Tado or similar.

Hive is my current preferred option as I have seen a good deal on an approved re-sellers website.

Our current system is a two zone using TP5000 controllers.

We have a Gledhill Boilermate SP and GB20 boiler.

For those unfamiliar, the Boilermate was installed in a lot of modern homes in the 2000’s.

It has a “Thermal Store” (basically a tank of hot water in a heavily insulated compartment).

The heating works by pumping water from the store (once a valve opens) round the radiators to heat them up.

The system also supplies mains pressure hot water.

The cold water passes through a heat exchanger and uses the heat from the “Thermal Store” water to heat the cold water and make instant hot water.

Although there is a timer function for heating and hot water, the default setting is “Constant”.

So the boiler fires on one of two conditions.

1) The temperature of the thermal store has dropped below its preset (so the boiler runs until the temperature sensors indicate it is back to normal)
2) One of the zones calls for heat.

From what I have seen of Hive, we probably need the Hive Single Channel Receiver

I removed the cover from the downstairs TP5000 and found that it only has 2 wires.

These appear to be connected to
Brown - COM
Black - N/O

There are 3 possible connections on the tab
A N/C
B COM
C N/O

The unit has batteries installed.

I can only ask assume that there is no requirement for mains power to the unit.

The Boilermate instructions show a typical installation using the TP5000 units


It however describes the connections as 1, 2 & 3 vs A,B & C

1) which I assume is A is connected to Live
3) which I assume is C is connected to Switched Live

My thought process is this

Hive has a Live & Neutral Connection as well as
1 Common
2 Heating Off N/C
3 Heating On N/O (see thumbnail image)

My understanding is that the Live & Neutral are used to power the Hive receiver.

So by connecting my Brown wire to Hive 1 and my Black wire to 2 Heating Off the system should work ?

The TP5000 is obviously a controller and thermostat built into one whereas the Hive controller is only the switching part of the circuit and the brains is the remote thermostat.

My other idea was to leave the other zone as is.

We do not use that room much, so it can continue to work off the TP5000 (I Hope)

So I am after some thoughts if my thinking is correct and anyone has come across the scenario with just 2 wires ?

There may well be a L,N & E tucked behind the TP5000 as I can see coloured wires that are in the wall behind the plate.

Otherwise I was going to take a spur from a mains socket to derive my L & N.

 

[stem]

You can swap the TP5000 for a Hive Single Channel. From an electrical point of view they provide identical control functions. Both are a simple 'on' and 'off' switch. The only difference is that whilst the TP5000 is battery powered, because Hive has WiFi built in, it requires more power than would be practical with a battery, so it has a 230V mains supply.

The brown wire at the TP5000 is the Live and would connect to the Hive Single Channel Version (L)
The black wire at the TP5000 is the Switched Live and would connect to the Hive Single Channel Version (3) 'Heating on'

The Hive will also need a neutral supply connecting to (N) This should come via the same 3A fused spur that supplies the rest of the heating system and not from a separate source. You may find that there is an unused grey wire in the existing cable that you could connect to provide this.

Finally a link between the Hive (L) and (1) 'Common' is required so that the terminals are electrically connected together.

A second Hive will be required for the other heating zone.

There is also a timer for hot water control, responsible for when the thermal store is heated which you presently have on constant.

If so, you might want to consider a dual channel Hive which could control the first heating zone and also the hot water in place of the Grasslin clock, and then another single channel Hive for the just the second heating zone. However some rewiring of the system would be required to bring the wiring from the first zone and the hot water timer together. However, if you presently have the thermal store heated 24/7 then that might not be an advantage to you.

 

[Hawkeye65]

Hi Stem,

Thanks for the clarification.

Silly me.

The Gledhill diagram shows Live going from the junction box to COM(1)(aka B Com on my photo) and the S/L going from the junction box to ON(3) (aka Normally open C on my photo)

Hive obviously does things a bit differently with the switching.

I don't know why they even have a connection for Heating Off N/C (2).

They should draw it with the relay shown so people can visualise how it switches.

Anyway from my photo it appears that I have Brown & Black connected, but tucked away are a grey and yellow/green.

I can only assume that they ran a 3 core and earth through the walls (photo above) so hopefully I can turn the power off and look to see if the grey wire is taped off.

If not, assuming they have not chopped it off in the Boilermate cabinet, it may be hanging loose waiting to be connected to the Neutral.

If not, is there anything to stop you installing the receiver in the airing cupboard (I could run fresh wires straight from the Gledhill Junction box to the receiver) or is it too warm to install the receiver in an airing cupboard.

I will probably stick with the water on Constant (we do not use the clock).

But I will need to read up on the differences between a Dual Channel Hive and a Single channel to see if it would benefit me.

Thanks again

 

[stem]

I don't know why they even have a connection for Heating Off N/C (2).

There are a few systems that use it, but they are about as rare as hens teeth these days.

is there anything to stop you installing the receiver in the airing cupboard (I could run fresh wires straight from the Gledhill Junction box to the receiver) or is it too warm to install the receiver in an airing cupboard.

The airing cupboard is where they are often installed in new builds, and I can't see any temperature spec in the Hive literature that would prohibit it. Just make sure it's not hidden behind the hot water cylinder which may screen the WiFi signals.

But I will need to read up on the differences between a Dual Channel Hive and a Single channel to see if it would benefit me.

The only difference is that the dual receiver has the additional facility to control hot water on/off times. So, you could have it set so that the Heatstore wasn't being heated overnight. It might save you a bit of energy, and if you are a light sleeper you won't be disturbed by the noise of it running during the night. Also if you went away for a few days / weeks you could stop heating up the Heatstore and just have it come on before you get home, so that it's charged up and ready to go when you arrive.

Another advantage, but one you might not have thought about is, that I have known of Heatstore's being taken out for various reasons, and traditional hot water cylinders being installed in their place. Should you do that, the dual channel Hive will still be able to control the heating of the new hot water cylinder.

 

[Hawkeye65]

Stem,

I am a light sleeper recently and I can hear the boiler firing in the night.

Our system also has a feature where the boiler starts and stops non stop every few weeks which is cured by topping up the water in the expansion loop. I don’t seem to be leaking water anywhere, so a bit of a mystery.

So the ability to turn off heating the thermal store between say 11pm & 6am would make sense.

I guess if the water was on timed but the heating called for heat, the water required for the radiators would still be heated by the boiler.

Looking at the Gledhill schematic, it seems that the Grasslin clock shares a Live & Neutral with Zone 1 & also has a link between terminals 1 & 3 (not sure what this link does yet, or if this link would be required on the hive)

I can only guess that the water Switched Live would connect to terminal 3 (Hot Water On ) on the Dual Channel Hive.

I could then leave ZONE 2 as is for the moment, make sure it all works and add a single zone hive later if required.

I think for the price difference it makes sense to get the dual receiver.

Assuming that the second TP5000 Zone 2 wiring is the same as Zone 1, then I guess the wiring would be the same as you mentioned in your initial reply, albeit using the Live, Neutral and SL from the second junction box.

Hopefully others with a Boilermate will be able to use this thread as a reference.

 

[stem]

You seem to have it all well figured out. I have only have had limited experience of a boilermate. (one only) so not sure how long it takes to heat up etc.,

Hot water on (3) would be the right Hive connection to use, and I guess you could heat up the heatstore in advance of the heating coming on if you wanted the radiators to heat up quickly. However, I imagine it retains much of its heat overnight anyway.