Honeywell Evohome questions

[redw0001]

Hi, I'm at the stage of agreeing what changes we make to our CH system starting from the boiler outwards. Already read about the Honeywell Evohome and just wanted to check some things with people that are using the system. I'm likely to end up with 10 zones, one with two rads.

1: I think the controller can act as a zone, so I could put that in one room and remove the need for the HR92, is that correct? Would I just put a 'normal' TRV on the rad as well? Could save me cost of an HR92.

2: The HR 92s look pretty big (checked the spec sheet). Is there any operational issue with horizontal mounting rather than vertical? Towel rail we are looking at seems to need the TRV to be mounted horizontally.

3: Has anyone had any signal strength issues? I'm coming from house with solid limestone walls but our new house is a 1980s house with block walls mostly. I calculate max distance from boiler to a TRV is just under 19mtrs. (it's actually a bungalow and the boiler is at far side of garage).

4: Anybody found a good supplier regarding price? I checked the Honeywell Evohome shop so far but cant help thinking I need to look further.

robin

[dty]

Welcome to the revolution!

1. The controller can act as a sensor. You'll still need an HR92 in the room if you want to get any kind of control.

2. They're certainly not small. They work fine horizontally, but the screen doesn't rotate so all the numbers are sideways.

3. I live in a 1950s cottage with half a dozen extension. Almost exclusively solid plastered walls. About 4000 sqft in total, so quite a long way from one end to the other. I had difficulty siting the controller so it could be seen by both ends of the house. It's not in my preferred location right now, but it does work. It's about 14m from the two extreme HR92s and I get occassional signal issues (maybe once every 2-3 weeks). If you get a Honeywell installer to do the job for you, they should come and do a signal check survey for you too. Alternatively, EvoHomeShop has a kit you can buy to do it yourself.

4. They're about the cheapest I've found. You can sometimes get bits cheaper on eBay, but... eBay! If you use a registered installer, you may find they can get bits cheaper - although my installer just buys from Richard any way!

If you're anywhere near the Surrey/Hampshire/Berkshire borders, I can recommend an installer.

[redw0001]

Wow, thank you for the quick response.
Great answers, but needless to say raises another question. Looking at the kit on the EvoHome shop I see 8 HR92s, the controller (with screen) and a wireless relay box. What do the HR92s communicate with, the controller or the wireless relay box?

From what you wrote I think I'd misunderstood the topology thinking that the HR92s talk to wireless relay box. If it is actually direct to the controller my distances will be halved.

[dty]

Yes, everything talks to the controller. And the controller talks to everything!

[dty]

If your house is 19m end to end (or corner to corner, or furthest TRV to furthest TRV), I doubt you'll have an issue. Wise to check though. Also consider that the relay boxes (BDR91, used to control valves and boiler depending on your configuration) also need to be in range. Mine have ended up in the airing cupboard because that's where all the things they need to wire into are. I suspect most people will be in a similar position.

[Vladiemier]

[Fireblade69]

Actually, #1 might not be strictly correct although it is by far the best option.

If the controller was the thermostat for that room then you could use that particular radiator as the bypass radiator and fit it with a normal TRV set to your ideal temperature. When that zone and that zone alone called for heat then it would fire the boiler and heat until the Evohome sensor got up to temperature then stop and the TRV would act in a normal way.

There is a snag though, a scenario where the radiator was turned down or off but the zone still called for heat would cause the room never to reach temperature and therefore the boiler would continue to try. Same if there was a draft/open window that the sensor was affected by by not the radiator. Neither are a good scenario and it is worth the extra ££ to avoid them by buying an HR92.

[paulockenden]

Don't forget that every zone needs an actuator as well as a sensor.

[DBMandrake]

Hi, I'm at the stage of agreeing what changes we make to our CH system starting from the boiler outwards. Already read about the Honeywell Evohome and just wanted to check some things with people that are using the system. I'm likely to end up with 10 zones, one with two rads.

1: I think the controller can act as a zone, so I could put that in one room and remove the need for the HR92, is that correct? Would I just put a 'normal' TRV on the rad as well? Could save me cost of an HR92.

As mentioned already you still need an HR92 if the controller is the temperature sensor of the zone.

2: The HR 92s look pretty big (checked the spec sheet). Is there any operational issue with horizontal mounting rather than vertical? Towel rail we are looking at seems to need the TRV to be mounted horizontally.

They're a lot smaller and slimmer than they seem from specs. They're hardly any bigger than a typical plastic bodied TRV, and they should have no trouble running on their side.

3: Has anyone had any signal strength issues? I'm coming from house with solid limestone walls but our new house is a 1980s house with block walls mostly. I calculate max distance from boiler to a TRV is just under 19mtrs. (it's actually a bungalow and the boiler is at far side of garage).

As has been mentioned, the controller itself is the device that all other devices communicate with - so if you thought it might be an issue, to maximise range and signal strength you would place the controller near the middle of the house, therefore the furthermost device would only be half the dimension of the house away so about 10 metres in your case.

We're also in a similar size bungalow (with loft conversion) with solid brick and plaster walls downstairs, I have the controller on a wall mount in the hallway which is approximately the middle of the ground floor - I wouldn't say that I have had any signal problems with HR92's. The only signal problems I've had were to the CS92A hot water sensor where I had to move it a bit to get a more reliable connection.

4: Anybody found a good supplier regarding price? I checked the Honeywell Evohome shop so far but cant help thinking I need to look further.

robin

I bought all my Evohome kit from the evohomeshop - one advantage you have in doing that is Richard provides good after sales support including phone/email and his own forum, and he knows his stuff. So if you run into any trouble and need advice you'd have him to fall back on. (Of course there are helpful people on this forum too)

His prices aren't the cheapest but they're not too far off if you buy enough to get free shipping.

[Mavis]

Quote ...2: The HR 92s look pretty big (checked the spec sheet). Is there any operational issue with horizontal mounting rather than vertical? Towel rail we are looking at seems to need the TRV to be mounted horizontally.
They're a lot smaller and slimmer than they seem from specs. They're hardly any bigger than a typical plastic bodied TRV, and they should have no trouble running on their side. End Quote

I have an HR92 on a towel rad in the bathroom and I have no problems with it. (see pic) (picture is on its side)

IMG_0082 (2).jpg