A few comments on HG, now I have a few minutes...

Biggest weakness for us is the wireless signal. We have a house with a number of extensions, so the signal has to go through a lot of brick, including double bricks where old external cavities are crossed. It took a while to work out the best layout. The key is that the only nodes that repeat the signal are the wired in ones - hub, boiler controller, plugs. It is very sensitive to objects placed around these nodes, especially metallic ones.

Now, the reason I asked which fuel was being used early on...

The system is very aggressive about shutting down the TRVs as it approaches the set temperature. This is good, but in some rooms you may find that you never actually reach the temperature, or stay at it. Because an oil boiler (as we have) doesn't modulate that means cycling.

There are new developments to work around this.

Well - I went for an evohome system.

It's been a bit of a nightmare getting it to work though. I was finding that the various components weren't communicating with each other properly. Spent many hours moving things around - but even when they were within a metre or two of each other there were still problems. Eventually I realised that the issues were related to another monitoring/datalogging system I have, which uses the same frequency. As soon as I unplugged the gateway box for that system, everything was fine. So, several more hours trying to find a new location for that box which caused the least interference.

I now have a sort-of working system (will see how it goes for the next few days). But for the time being I've given up trying to get the radiator valve in one room to work.

I thought the idea was that several systems could co-exist on the 868Mhz by using their own unique signals. But in practice this isn't working. I don't know if the other system is to blame for dominating the airwaves, or whether the Evohome components just have rather feeble transmitting powers (they seem to be affected by signals from the other box, even if it's 3 or 4 times more distant than the evohome elements are from one another).

Posted By: djh

Posted By: lineweightwhether the Evohome components just have rather feeble transmitting powers (they seem to be affected by signals from the other box, even if it's 3 or 4 times more distant than the evohome elements are from one another)

It might also be that they have poor antennae for receiving signals? Any facility to upgrade the antennae?

Maybe... discussed in this thread a bit:

http://www.automatedhome.co.uk/vbulletin/showthread.php?4442-Evohome-range-issues

(which I've also posted on)

A "stupid" low level protocol is sometimes the right choice. What's why ethernet beat token ring in almost all use cases.

Although, granted, it depends on the use case being discussed. It sounds like ACKs are not the issue here, although I may be wrong!

As above network coverage has been the main issue with our HG system (Z Wave based, similar frequency I think). I thin we've got it cracked now. Just had to understand the repeating nodes, which node types were better than others for fault tolerance of routes etc. Our house is bad because a lot of brick for the signal to go through.

It's a relative measure, ethernet is stupider, certainly less controlled. It turns out that the economics (not the financial ones) mean it doesn't matter.

The point is there's nothing inherently wrong with not ACKing, there're multiple levels of abstraction above to make up for that.

Apologies for taking us off topic.

Posted By: lineweightI've spent so much time messing around trying to get the Evohome system to work that I think it would actually have been quicker to take a load of floorboards up and put in a fully wired system (I've already had to run about 6m of cable to try and get the boiler relay in a location where it can "hear" anything). And it still isn't functioning as it should.

There seem to be very few options that use cables these days!

3 years later I'm reactivating this thread because the Evohome system I've had installed during that time has never quite worked entirely.

Just wondering if any other alternatives might have appeared on the scene in that time that people have had success with?

Posted By: DamonHDWell Radbot has finally made it through manufacturing and is available (https://www.vestemi.com/radbot/" rel="nofollow" >https://www.vestemi.com/radbot/). Yes, I have a commercial interest, though the motivation is carbon emissions reduction...

Note that this is not a system targeted at early adopters or geeks as sold, though in principle in can do many geeky things. This is kept as simple and as cheap as possible for 'normals'! For those of you that care about these things this is built on the OpenTRV open source base, and we have worked to make is possible for geeks to use it and plug it into their systems, but we're not quite there yet.

Rgds

Damon

Looking at the website...it's not really a true zoned system is it? As in, the valves don't communicate with the boiler, so like traditional TRVs they only do anything when there's heat called from the boiler by a central timer or stat.

Posted By: DamonHDIt is fully soft zoned, ie each rad is its own zone. No pipework changes needed.

The units sold do transmit (encrypted) calls for heat, and several installations including my home control the boiler that way, and the code and schematics of the boiler control unit are open source. For installation and marketing simplicity we are not selling that boiler control unit yet.

I'm not saying that Radbot is necessarily right for you, just responding to your earlier post.

Rgds

Damon

Ah, ok.

My setup is that most calls for heating are for one of three individual rooms only, usually just for a period of time and not for the main living area which thanks to insulation hardly ever needs heating. This means that I need something that lets the boiler be 'off' for most of the time, but which can still provide heat on demand to certain zones only.

I'd be interested to see if/when you start selling the central control unit.

Only for the geeky (and I've no experience) but worth mentioning that with some hacking + open source software it's possible to put together a system using components from more than one supplier - not just climate control, but lighting, audio, other devices, etc. As I understand it, two leading control systems are Home Assistant and openHAB.

Intro to Home Assistant: https://www.youtube.com/watch?v=pVxoSXeC2Jw