Hive MultiZone - British Gas no help!

[Sul007]

OK, so I've just had a new boiler installed and changed my single channel to dual channel receiver.

Thermostats in the kitchen (don't ask me why the engineer installed there...) What I've discovered is as soon as the temp. hits the target in the room its in, it considers all the rooms in the house at the same temp which is the furthest from the truth. Upstairs is always much colder - which results in me having to take the thermostat upstairs to get the heating upstairs working.

Is this how hive works?!?!

If so, then I'm thinking I need a multizone setup - I've tried to call British Gas/Hive to try and get this setup and theyve quoted me £100 which cant be right as I need pipes redone from upstairs to the boiler. That being said they said I can use my old thermostat paired up with the same receiver as an alternative solution. But how does that make sense? If I want a floor hotter than another floor how is the boiler going to manage that without any pipework done?

Can I setup 2 thermostats to 1 receiver?

How much will it cost to setup a multizone setup if it involves piping re-doing?

 

[ericmark]

No Hive uses a demand for heat signal from the Hive electronic TRV heads which turns on the wall thermostat even if that room is warm enough until all rooms with the Hive TRV heads are warm enough.

Personally I think Hive is expensive the wall thermostat is cheap but the linked TRV heads are expensive.

So the old idea was to fit a wall thermostat in the coolest room, normally down stairs as heat raises, and not with an outside door, and not with alternative heating, so kitchen out as cooking gives off heat, hall out as outside door, living room out as not the coolest room, so many homes there is no room that complies with criteria so we need a compromise.

Hive is one way around the problem, as any cool room you just fit a Hive TRV heads and cured, at least in theory. I really like the idea, so simple, what I don't like is the price.

 

[Deleted member 267285]

Is the thermostat in the kitchen or the receiver? That’s how any thermostat works, it’s just that’s wireless so you can move it to different rooms if you wish. Once up to temperature then it’s satisfied that the room it’s in (room thermostat - clues in the name) that it will turn the boiler off until it cools or needs to be hotter from a higher call for heat.

Is there a radiator and trv in the kitchen? Have you tried the Hive in a cooler part of the house, like the hallway?

 

[Sul007]

Is the thermostat in the kitchen or the receiver? That’s how any thermostat works, it’s just that’s wireless so you can move it to different rooms if you wish. Once up to temperature then it’s satisfied that the room it’s in (room thermostat - clues in the name) that it will turn the boiler off until it cools or needs to be hotter from a higher call for heat.

Is there a radiator and trv in the kitchen? Have you tried the Hive in a cooler part of the house, like the hallway?

Both are in the kitchen - receiver near boiler and thermostat installed by BG engineer next to it ffs.

OK so that's what I'm doing now, moving the thermostat around the house but its frustrating having to move around the house to the coldest room. Just because its hit its target downstairs doesn't mean upstairs has - plus yesterday the corridor was very cold with the heaters off - until I placed the thermostat in the hallways they then immediately went on.

So it looks like I need a multi-zone setup but doubtful it can be done for £100 as they are requesting - can I pair 2 thermostats to the same dual channel receiver as British Gas/Hive said I could? They didn't convince me they knew what they were talking about and hence trying to confirm with more knowledgeable people.

I don't have any of TRVs - so guessing that would be a cheaper alternative to buy Hive's TRVs then getting a multi-zone setup right?

Anyone ever got the multi-zone setup - as in get all the pipes diverted from upstairs to the boiler downstairs?

 

[ericmark]

As @Chris_W says the Hive sender can be moved, however years ago with the old system we would put the wall thermostat in the most used room, and use the lock shield valves to set the proportion of the heat that goes to other rooms, so if other rooms too cold then turn down the lock shield in room with thermostat, and if other rooms to hot then turn down the lock shield in other rooms.

However when the condensing boiler came out, the boiler had to modulate to keep the return water cool enough, so we had to use the thermostatic radiator valve (TRV) and this means with no wall thermostat, each room is controlled in temperature by the TRV and once they all close then the by-pass valve opens and the boiler output is controlled by the temperature of return water, and each room is independently controlled.

However there is a problem, on a warm day there is nothing to tell the boiler it is not required, and even if there was with no water circulating there is nothing to tell it to switch back on again. So we need a wall thermostat, there are a number of types of wall thermostat, simple on/off, mid range on/off with anti hysteresis software which pulses off/on when it gets near to set temperature so it does not over shoot, then top range on/off where it works out when to switch off using algorithms and memory so it does not over shoot, and analogue often called opentherm where it gradually turns down boiler as the room warms up which in the main is the best.

However we don't want to heat one room but many, so we also have the TRV that links to the wall thermostat, Honeywell EvoHome was one of the first, and it needed an extra module to work with opentherm, Drayton has a very good system where the TRV head works out when to turn down so heats the room up faster, Nest for some reason stopped using TRV links, and Hive came out with a system which although simple on/off had a lot of the features of the more expensive systems, and the way it has done it is the demand for heat system which seems to be unique. So the wall thermostat is more like a hub than a simple wall thermostat collecting info from the TRV heads, so each time a TRV head sends a signal that it needs heat, the wall thermostat well really the base for wall thermostat runs the boiler for ½ an hour, so it lets the boiler set the output using the return water temperature but can turn boiler off when not required.

However unlike the Honeywell EvoHome which tends to be sold as a kit for a number of rooms, it is sold as a wall thermostat and you decide how many TRV's you want to talk to it. Since if boiler turns off you waste energy and each TRV sends a signal every ½ hour you want at least 2 TRV's so it only turns off once whole house warm.

If the boiler turns off because the return water is too hot, then it has already been running at low output so very little heat goes out of the flue, and when it turns back on it turns on at low output, but is the wall thermostat turns it off, likely it is hotter so more heat lost out of the flue, and it turns on again at full output, so you want the wall thermostat (unless opentherm) to only turn off when every room is warm enough. You don't want a wall thermostat to cycle with a modern gas boiler.

Oil is different very few modulate and when they do not by much, so the old type thermostat is still made for oil boilers.

 

[stem]

It's not the Hive that's at fault the thermostat is located in the wrong place. As you have figured, it will turn off the entire heating system when the set temperature is reached, therefore it should be located in one of the last rooms to warm up, not one of the first. That way the all of the rooms are warm before the Hive shuts the heating down. As @Chris_W and @ericmark say the thermostat is battery operated and can be moved to a more suitable location. So, here are some tips:

1. The room thermostat should be in a room that is not effected by other sources of heat such as an open fire, cooking equipment, or direct sunlight etc. It should not be somewhere drafty or too close to a window, especially if it's one that is opened in the winter.

2. It should be in a cool room, ideally the last to warm up. That way the other rooms will be warm enough, (but not overheated if fitted with TRV’s) before the room thermostat switches the entire heating system off. [To achieve this, sometimes it may involve downsizing a radiator in the room where the room stat is located]

3. The radiator in the room with the thermostat installed should not have a TRV fitted. Otherwise the TRV could interfere with the operation of the room thermostat and prevent it from working properly.

4. The thermostat should be mounted about 1.5 metres from the floor, and not close to, or above a radiator.

5. Preferably it should not be on an outside wall, (although if the property has well insulated walls, this is not quite so crucial.)

6. It should be in an area where air can circulate easily, not in a corner, or hidden behind curtains, or furniture.

 

[Deleted member 267285]

Just to add as well, the room thermostat controls the heating, not the trv’s, unless it’s setup differently with the smart trvs - which you have already stated you do not have.

 

[ianmcd]

yes you can have two thermostats connected to the same receiver , but you will also need two zone valves installed that the thermostats will control, you will not get that done for £100

 

[Connor.samuels]

just in case anyone was wondering here , you can have two thermostats linked to the same receiver. This will both work as one system, so they will take the average of both readings and keep it at the level you set. This will also only show the same single reading on the hive app (you can’t see both / several readings like with the radiator valves) .
Alternatively, you can buy an additional receiver for the second thermostat which will give you two separate zones but without any plumbing / valves it will heat the entire home to get the thermostat up to temp.
We have a baby and needed his room maintained to a temp so this method worked best for us. The radiator valves are a bit hit and miss with temp as they tend to be close to the window, so will show colder than they are sometimes depending on your home.