Hive Install to replace Danfoss TPOne - B

[Red-DiY]

Hi All
Kindly asking for help.
Just moved to a property that has Ideal Combi Boiler with 2 Zones.
Each Zone has its own Thermostat - Danfoss TPOne - B
The TPOne is battery operated and acts as a Thermostat and Programmer hence there is no standalone programmer near the boiler.
I have got Hive Mini and Receiver from my previous property where I installed without any problems.
The wiring in the TPOne is just 2 wires Brown and Black. How do I install Hive receiver which requires L, N, Earth plus switch Live?
Also behind the TPOne 2 wires are not attached to anything. Grey and Earth
Thanks in advance

 

[RandomGrinch]

The wiring in the TPOne is just 2 wires Brown and Black. How do I install Hive receiver which requires L, N, Earth plus switch Live?
Also behind the TPOne 2 wires are not attached to anything. Grey and Earth

Near to the zone valves, there will probably be a small wiring centre.
If you can find this, we can investigate the wiring connections on the other end of the TPOne cable.
We would need to find the other end of that spare grey wire and connect it to a Neutral terminal, to allow the Hive receiver to power up.

 

[ericmark]

Since two zones, it is likely there is a wiring centre and zone valves, as @RandomGrinch says, most zone valves are 230 volt (low voltage) however Hive thermostats only seem to come as single or two channel, the Wiser has a three channel version but this does not seem to be available with Hive, and second channel is for water, so for two zones you need three channel version.

The hub or receiver as hive calls it, is mounted near the boiler, it has no temperature sensors in the hub/receiver, the temperature sensors are in the TRV or wireless thermostat. So the existing wiring to the thermostats becomes redundant.

I would say you need to consider the heating as a whole to start with, and look at what your goals are. I did consider Hive myself, it was a toss up hive or wiser, both very similar, but there are some differences, Wiser will work with OpenTherm although my boiler does not have that option, but what stopped me using Hive was the 22ºC limit when accepting demands for heat, I really don't care if living room is at 22ºC already, if wife's bedroom is at 16ºC then I want the boiler to fire up.

I have Nest in the hall, and with last house that worked, but this house hall cools to slowly, Hive it seems is designed to go in a room kept cool, like the hall, to be frank, could not really care less what temperature the hall is, we only pass through it, we spend no time in the hall, I do care what living room and bedroom temperatures are, so went with Wiser so I can add a linked TRV in wife's bedroom.

Neither the Nest or the Wiser geofencing has impressed me, Wiser uses IFTTT, maybe Hive geofencing is better? But I simply rely on times, the house simply does not heat up fast enough for geofencing to work. Lived in 4 homes with central heating, and each one very different, but you need to work out what you need, I note the three channel Wiser is far more expensive to the single channel version, and with linked TRV heads is there any need for zone valves?

 

[RandomGrinch]

so for two zones you need three channel version.

No, they would have two single channel versions.
Hive multizone will combine them in the app.

The hub or receiver as hive calls it, is mounted near the boiler, it has no temperature sensors in the hub/receiver, the temperature sensors are in the TRV or wireless thermostat. So the existing wiring to the thermostats becomes redundant.

No, the hub is the device that connects to the router.
The receiver could be mounted next to the wiring centre in a two zone system, for convenience - alternatively it could be mounted where the old thermostat was.
There is no harm utilising the old wiring, but you would be left with an unsightly receiver on the wall - however this may be the better option for wireless reception, I.e. if the boiler and zone valves were installed in the garage.

I would say you need to consider the heating as a whole to start with, and look at what your goals are. I did consider Hive myself

The OP already has a Hive and is used to it; why not use it again, rather than adding to the Ewaste mountain?

I note the three channel Wiser is far more expensive to the single channel version, and with linked TRV heads is there any need for zone valves?

There may not be a need for separate zones, but with recent building regs requiring at least two zones on building >150m2, zone valves are the least cost option for developers; they're going to be around for a while.

 

[ericmark]

There may not be a need for separate zones, but with recent building regs requiring at least two zones on building >150m2, zone valves are the least cost option for developers; they're going to be around for a while.

Reading what the LABC has said on their websites, it seems TRV's are considered as forming zones.

The rest of what you say, seems good. So only down side of Hive, is the 22ºC limit to taking a demand for heat.

I used the two cores flat to garage to power and take info to Nest Gen 3, so it does not need batteries or rely on wireless links, however its inability to link to TRV's in a meaningful way, resulted in needing to install Wiser in parallel with the Nest. So in real terms Nest runs the DHW and Wiser runs the CH, most of the time. But on the odd time when we light a fire in the living room, Nest will then stop rest of house getting cold, until such time as I add linked TRV heads to Wiser.

But for @Red-DiY he would need to get a supply to the receiver, even if his Hive is volt free model, to get the supply to the receiver is likely to be a lot more work to mounting the receiver close to the motorised valves.

 

[ConcreteCow]

It sounds like you’re hoping to replace the Danfoss TPOne with your Hive Mini setup. Since the Hive receiver needs L, N, Earth, and a switched Live, you’ll likely need to identify which wires in your current setup can be repurposed for this.

 

[RandomGrinch]

Reading what the LABC has said on their websites, it seems TRV's are considered as forming zones.

Standard TRVs are not considered as forming their own zones, the guidance is that "Both zones must have heating controls through a thermostat AND individual TRVs" *my bold!

So only down side of Hive, is the 22ºC limit to taking a demand for heat.

I for one find 22C a little too warm!

 

[ericmark]

I Hive or Wiser TRV head can't be classed as standard, but what is the difference between a TRV and a zone valve? In the main a zone valve is on/off, and a TRV is up/down, and the boilers in the main are designed for up/down control. OK not mine as using oil, but most boiler regulate their output by the temperature of the return water, and to switch the boiler on/off rather than allow it to modulate as it is designed to do, will reduce the efficiency of the boiler.

 

[RandomGrinch]

But for @Red-DiY he would need to get a supply to the receiver, even if his Hive is volt free model, to get the supply to the receiver is likely to be a lot more work to mounting the receiver close to the motorised valves.

The developers often use very similar wiring methods.
If we do see inside the OPs wiring centre, it is likely that the grey wire is terminated in a spare way of the terminal block, along with the grey wire of the other stat.
It's usually a simple job to move the grey over to a Neutral, and the wirings ready to translate to the Hive at the other end.
A wiring centre can sometimes be a daunting place!

 

[ericmark]

There is no "and" reading further through Part L approved document it does say:-

6.51 Comfort cooling systems should have both of the following controls.
a. For each control zone and for each terminal unit, independent control of both of the following
should be possible.
i. Timing.
ii. Temperature.
b. If both heating and cooling are provided in the same space, the controls should prevent them
from operating simultaneously.

but seems the only cooling needs a time control, it says

I know the approved document is not the law, but reading the approved document it does seem to question if using a zone valve connected to a thermostat would comply, one as it does not have a time setting, and two as at least with my house my rooms don't have the same thermal characteristics and temperature control requirements, each one is different.

It also raises the question is geofencing permitted? As this does not use time, but occupancy, or at least future occupancy, after a couple of cold days after high winds took out the EE mobile phone app, I disabled my geofencing, the problem was the PIR built into the Nest Gen 3 thermostat would put the system back into comfort mode each time we walked past, so I was unaware it was returning to Eco mode, and 16ºC was not warm enough for me, it was not until I went into the computer program did I realise what was happening.

 

[RandomGrinch]

Apologies to the OP, for the digression.

There is no "and" reading further through Part L approved document it does say:-

You originally stated that you were looking at the guidance on the LABC website, rather than at Part L - I quoted the "And" from the LABC technical update, from their website.

I know the approved document is not the law, but reading the approved document it does seem to question if using a zone valve connected to a thermostat would comply,

and I don't know which part of Part L you are looking at, but the intention seems clear..

 

[ericmark]

The problem is, the TRV is a thermostat, so "Thermostatic radiator valves should not ne used in the same room as the thermostat" does not make sense, I can see that if following the idea that a wall thermostat is used in a room normally kept cool, with no other form of heating (that includes sun through the windows) on the lower floor, clearly as heat raises, and with no outside doors, then there is no need for a TRV on the radiator in that room, once used the lock shield valve to adjust heating speed, so that is the slowest room to heat.

However back in the real world, that room seldom exists, so the normal is to use the hall, which does have an outside door, so one does need a TRV and a wall thermostat in the same room.

Sequence of events is, door to outside opened, the two thermostats call for heat, and the room heats from say 12ºC to 17ºC reasonably fast, at which point the TRV starts to close, it takes around 3ºC between TRV fully open and fully closed, and the wall thermostat is higher than the TRV, so the heating is reduced so it takes quite a long time for the room to hit 20ºC where the wall thermostat is placed, so giving time for the rest of the home to heat up.

This assumes mechanical TRV's and single wall thermostat.

Once we move to electronic TRV's linked, then there is simply no need for any wall thermostat, both Wiser and EvoHome can run with the TRV heads alone sensing room temperatures, and each room is its own zone, the earlier EvoHome has a display to show temperatures in each room,

the latter Wiser does it with the phone app. The Wiser can have zone valves as well, which for a house like mine, with one boiler heating two independent dwelling that makes sense, but in the main, zone valves are not required.

 

[Red-DiY]

Hi All
A tremendous thanks for the replies so far.
As I already have the Hive minis I would prefer to use these if at possible - the missus is not gonna be happy othereise from a cost point of view.
Later on today I will get to the Wiring Centre and investigate.
I will get some pictures and upload.
Thanks

 

[Red-DiY]

I have opened the Wiring Centre - please see photos
Thanks

 

[RandomGrinch]

I have opened the Wiring Centre - please see photos

Thanks for the photos.

Two things to note, first the grey wire is already connected to neutral - a little bit poor, considering it is just hanging out loose, in the backbox of your existing stat.
Secondly, one of the brown zone valve wires has been trapped by the lid of the wiring centre - it shouldn't be an issue, but just make sure its clear of the lid before replacing it.

Next, it depends on what you want to acheive.

If you are happy with your single channel Hive receiver replacing the existing stat...

With the power safely isolated,

Connect the Brown wire to the L terminal of the Hive receiver backplate.
Connect the Grey wire to N.
Connect the Black wire to terminal 3
Put the Green/Yellow earth wire into Hives earth terminal.
Then add a short link wire between L and terminal 1.

Alternatively, for a neater finish, if you would like to put the Hive Receivers near to the wiring centre, we can guide you through the rewiring and decommissioning of your existing stats.