Hi there... I had to work a bit to find out an R8810 OpenTherm Gateway for my EvoHome system, I live in Italy and we are A LOT behind with this stuff.

Now I had an early implementation of my "DIY" EvoHome system, with two motorised zone valves for my old-style two zones (planning to switch to HR92s as soon as I can afford 11 of them ;-) ). Two BDR91 are driving those valves, that have an embedded switch that I used to control my (combined Ferroli BlueHelix Pro 32) boiler. So far, so good. Just a little puzzled about the continuous cycling of the zones/boiler when the actual temperature approaches the setpoint, but used to work quite reliably.

Now, since my boiler supports OpenTherm, I bought the Honeywell R8810 and set it up to control my boiler (just disconnected the wires from the valves switches and connected the R8810). First, the R8810 itself wasn't easy to pair to my Evohome controller. I tried several times, usually I get them paired after 8/10 tries...

Once the R8810 is paired... the behaviour gets odd. Sometimes it calls heat with both the zone valves shut off (that sets the boiler on, while water can't flow). Sometimes the other way round happens: zone valves open, boiler not firing.

Some other times, it seemed as the R8810 lost control capabilities to the boiler. Once it actually lost communications (I received a notification by email).

It's pretty weird that performing an RF test, the R8810 LED flashes red 5 times (that should mean excellent reception), but, differently from BDR91, the EvoHome display doesn't show any feedback.

Does anyone have any experience with an R8810? Is it always a nightmare, or maybe I have a faulty unit?


Thanks!

M