Room thermostat controlling rads & boiler. OpenTherm?

[russella]

Jack,

Have you checked out the FS20 system?

http://www1.conrad-uk.com/scripts/w...lay=&catalogs_sub_id=sub4&aktiv=4&navi=oben_2

Househeat sell the same stuff in the UK without any branding on, but it's around 20% more expensive.

We've just fitted this in our house, standard 3 bed semi, it's cost us around 50 quid per room (so around £350), plus we need to spend another 80 quid for the boiler control system. Sounds like it does exactly what you need, and it's all wireless. We spent around 30 quid on good-quality long-life rechargable AA batteries as well, so all in just shy of 500 quid.

Also no need to do any re-plumbing, the motorised valves fit on top of most standard TRVs. So far our experiences have been really good!

Russ

 

[JackKelly]

Jack,

Have you checked out the FS20 system?

That does look interesting, many thanks. I had a look through the FS20 range on the Conrad site but I couldn't see any boiler control modules. Which boiler control module did you go for?

Many thanks,
Jack

updateI've read a bit more about this system. I'm starting to like what I see! Like you say, it looks like it does everything I want, including remote control from an iPhone . Thanks loads for pointing me towards it.

But one of the things which still confuses me is: I haven't yet found any mention of a way to get the FS20 system to directly communicate with the boiler. I've skim read the manual for the FHZ1000 Wireless Heating Control system but haven't found any way to hook it up to the boiler. Any clues?

Also, I've heard a few people mumble about the build quality. Are you happy with the kit so far? Is it built well? Does it behave itself? Is it easy to control?

Thanks again!
Jack

 

[dreadnoughtheating]

JK, YGWYPF, go with the Honeywell CM system, (RF stats on the rads - control boiler firing).

Its Honeywell, it works.

No, not the cheapest, but it is Honeywell. (Geddit?)

DH

 

[russella]

But one of the things which still confuses me is: I haven't yet found any mention of a way to get the FS20 system to directly communicate with the boiler. I've skim read the manual for the FHZ1000 Wireless Heating Control system but haven't found any way to hook it up to the boiler. Any clues?

Also, I've heard a few people mumble about the build quality. Are you happy with the kit so far? Is it built well? Does it behave itself? Is it easy to control?

A lot of useful information that got me started is at the following url:

http://www.automatedhome.co.uk/vbulletin/showthread.php?s=13d65f2528b4ec0a411d74da4bcff048&t=2050

I quote "Each FHT thermostat has 2 on / off time zones with target and setback temperatures. They then talk to the FHT8W (boiler controller) and tell it when there's a heating demand."

With regards to the build quality, I've had 7 of the thermostats and 8 of the valves, I've had two problems so far. One of the thermostats had a problem crop up with the LCD but there's a 2 year manufacturer warranty (according to the reseller) so that got replaced no problem.

The other problem I'm not sure whether to worry about at the moment - apparently when the thermostat sends a signal to the valve, the valve cannot respond to say "Message received", so if for some reason the message isn't received, the valve just doesn't respond. I've only seen it happen once so far in the month or two we've had the system running, and in practice it's not a big deal as the thermostat actually communicates quite regularly with the valve.

Russ

 

[simond]

We've got quite a few Hometronics installed out there and have found there are less problems with it than conventional things like boilers.

For a complex system it works very well and it has been out there for around 10 years in Germany. It is sold across Europe (except France) and is also available in the US.

There are many different ways of zoning your home heating and I'm not denying Hometronic is expensive, but in my eyes it remains the one everyone has to beat.

I installed a 28 head Hometronic in my own house about 4 yrs back, and I haven't had to do anything to it other than change a handful of AA batteries. Out of all our customers (and I would estimate there are about 400 heads we have put in) I can only recall changing 2 HR80 heads.

So Hometronic gets my vote for retrofit; for new installs there are other ways which may be more cost effective.

 

[wollo]

S plan anyone?

 

[onlyfitidealboilers]

Many thanks for the replies. All interesting stuff.

What am I trying to achieve? I'm trying to ensure that we only heat rooms when they're occupied. We don't have a huge house (main bedroom, spare room, study, kitchen, livingroom, dining room). At the moment we have TRVs on all the radiators and we manually turn them on and off.

Here's a typical evening:

8pm = dinner in the kitchen
9pm = watching TV in the living room
11:30pm = bed!

At the moment this means that I have to do this:

At 8pm = turn on the TRV in the kitchen and make sure all the other TRVs are off.
At 8:30pm = turn the livingroom TRV on to give the livingroom time to heat up.
At 9pm = turn the kitchen TRV off and we move to the livingroom.
At 11pm = go upstairs to turn the bedroom TRV on.
At 11:30pm = turn the kitchen TRV off and we go to bed

What I want is a way to automate this!

As far as I can tell, my best bet is to use programmable room thermostats in each room. These thermostats will control radiator actuators. Ideally I'd like the room thermostats to also ask the boiler to turn on so the boiler and pump turns off entirely when there's no demand for heat in the occupied room(s)

Why do I want the room thermostats to communicate with the boiler? Consider the situation where all the programmable room thermostats are above their target temperatures and so their radiators of closed. Without a way for the room thermostats to communicate with the boiler, the boiler's pump will continue running, wasting electrical power. Granted, the boiler will monitor the return temp and won't fire very often but it will still continue to fire because the CH circuit will be losing heat through the pipework and the bathroom radiator.

In my absolutely ideal system, the room thermostats would send detailed temperature readings to the boiler so the boiler can modulate optimally. And, in an absolutely ideal world, I and my wife would be able to use our smart phones to view and modify the room timers and target temperatures (say, for example, we go out for a drink instead of coming home at 8pm and hence we want to delay the heating until 11:30pm. Or say we're watching a film in the livingroom and we want to delay the bedroom's radiators until midnight).

What's the ultimate aim? To minimise gas consumption whilst maximising comfort.

my goodness, get a life mate!!!

 

[NickCh]

I moved into a house a couple of months ago which had been completely renovated 4 years ago, great central heating system but amazingly no central stat, just control via timed programmes on the boiler out in the garage.

This gave me the task of looking for a decent programmable stat, which in turn gave me pause for thought on some means of intelligently controlling the call for heat within my new home - I work from home more often than not, and the idea of being able to only heat my study in the winter and the sitting room/lounge for half an hour at lunchtime was appealing, as was controlling the heat in a couple of rooms that would only be used at weekends and so on.

I spent £700 on househeat wireless digital thermostats and radiator actuators (which I think are actually manufactured by eq-3) to control 14 rads, including their boilerconnect box which ensures the boiler and pump are only active if one of the 24x365 profiles in any of the 12 zones is calling for heat. It might sound a lot, but I know I will spend 30+ years in this house (although if I move out next year I can take all of it with me) and it will easily save me 20% on my exorbitant heating costs each year.

I think it is fantastic - the only problem is that having increasing amounts of control on the energy consumption is addictive, and I now am looking at various home autonomy software and hardware to bring my home up to a truly intelligent level.

Being able to schedule on a weekly basis exactly what each room does in terms of demanded and achieved temperature is really impressive, as is the ease of walking into a room not expected to be occupied and at the press of a button the room rises to the previously established comfortable temperature within around 10 mins.

Give it some thought

 

[flameport]

This is very old thread, however heating only one or two rooms in a house saves very little or even nothing, since the heat losses from the heated room will be far higher when the adjacent rooms are cold.

There is also the issue of the boiler output being far too high for just a couple of radiators, which will mean it is less efficient than when heating the whole building.

 

[NickCh]

Thanks for that, I'm very interested in where I can find some reputable calculations around this subject of what ranges of temperatures to keep your house zones in for best efficiency - the selling blurb for the kit I bought made the same point as you around it being more energy efficient to keep the house at a certain level being more efficient then treating it as a binary problem effectively switching it on and off.

The kit doesn't treat it as on/off though, you set an occupied and unoccupied temperature range for each room/zone.

This subject that you raise affects what lower temperature I set on the unoccupied rooms - I need to find an efficient value. I started out with 13 deg C set as the unoccupied temp but have recently been revising it downwards probably in ignorance after finding the spare bedroom triggering the heating when the rest of the occupied bit of the house was comfortable.

Do you or anyone else know of any good energy studies that give guidance on the most efficient way to heat bricks and mortar (probably breeze block in my case)?

Many thanks