Hive Installation

[Speedster]

Hi,

I have just bought a Hive self install for a combi boiler, there is no external programmer - this is integrated into the boiler itself. Can I just replace the existing wired thermostat on the wall with the Hive receiver? I cannot see any controller anywhere near the boiler so assume that there is a direct connection between the existing thermostat and the boiler.

 

[stem]

The answer is probably. But....

1) There are hundreds of different boiler & thermostat combinations out there and they are not all wired the same. The Hive requires a 230V mains supply to operate, not all thermostats do, or have a 230V supply connected to them. So you may have to run a new 230V supply to the Hive receiver to power it.

2) As well as temperature control, the Hive will also take over the time control functions of the internal programmer which will no longer be needed. So to prevent the existing programmer interfering with the operation of the Hive, it either needs to have its wiring modified to wire it out of the circuit [This may have to be done by a Gas Safe engineer if it involves opening up the room sealed part of the boiler] or it can be simply set to be permanently 'on' 24/7 which will allow the Hive to take full control.

 

[Speedster]

Thanks for the reply, I currently have a Honeywell T40 with the wiring as per attached, as you can see there doesn't seem to be a neutral wire and have a Main 30 boiler where I currently have the heating set on 24/7 and its just controlled on/off by the thermostat. Any advice?

 

[EFLImpudence]

There isn't a brown or anything in '2'.

You only have a live and switched live - '1' and '3'.
You therefore cannot put the receiver there, not that that is a sensible idea.

Don't you just need a battery powered progammable thermostat?



Wires don't know what colour they are. Blue doesn't always mean it is a Neutral.

 

[Speedster]

Thanks, sorry was a typo have edited the post. It makes sense now that 1 and 3 are live.There is no neutral it might be best to get it installed professionally

 

[Taylortwocities]

Maybe I’m missing something. Why would you have the Hive receiver at the old thermostat location? The logical place is at the boiler, or the system wiring centre/where the programmer is.

That is where you’ll find all the connections you need, including the live, call for heat and neutral.
The thermostat goes where the old one is, or somewhere else.

 

[stem]

Quite a few folks seem to over simplify it a bit, thinking that as they are buying a new thermostat, it must replace the old thermostat. Missing out completely that it is also a 'programmer'. However, I think that there are also other reasons.

For a lot of DIyers the wiring centre understandably frightens them. The cables are rarely marked as to what they do, blue wires are frequently used as live conductors without additional marking, and the whole thing frequently resembles a rats nest. Almost every one is wired differently to some extent, so it's not fixed what each terminal does, and has to be worked out. Even for those that know what's going on it can be difficult sometimes to understand what each wire does, (especially from just a photograph). In this instance it's a combi anyway, so unlikely to have a wiring centre.

For many combi's, the Thermostat does have all of the wires necessary, so makes an easy installation point, and the function of each wire can be easily identified by the terminal markings on the thermostat.

Also, recently, it has become more common for boiler manufacturers to house the boiler wiring terminals inside the room sealed cover, Thus making them inaccessible to DIYers (and sparkies for that matter) without the presence of a gas safe engineer. A thread discussing it and a provisional list of boilers possibly affected can be found here.

 

[stem]

Thanks for the reply, I currently have a Honeywell T40 with the wiring as per attached, as you can see there doesn't seem to be a neutral wire

Which is wrong. There should be a neutral wire connected to terminal 2, to operate a device called an 'accelerator' that improves the switching accuracy of the thermostat. It will work, but not as well as it could do.

Sadly, having that thermostat you should have been one of the lucky ones, and had all the wires present you need. [It's usually just the battery operated thermostats that don't have a neutral] but as the original installer messed up....

Don't you just need a battery powered progammable thermostat?

This would seem like a good idea to me, unless you really need to have the facility to adjust your heating when you are out shopping or down the pub.