Help - Combi Boiler, Thermostat and TRV Setup

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Can anyone please advise on the devices I should consider for a heating setup and how it might work.

I live in Spain and currently have a Tado thermostat wired to my combi boiler and have been considering their radiator valves. However, having recently bought a Hubitat and dimmer modules I would prefer local control. And whilst the Tado system works well, I need a thermostat with inbuilt programming control so that my partner and I can program it directly at the unit without needing to go into an app or a hub.

Searching a lot I can't find a direct z wave/zigbee replacement for the whole Tado system. There are boiler receiver/switches from a couple of companies, a few wired thermostats from others, none of which claim to be able to control a gas boiler directly and a few radiator valves from others.

First question is whether anyone knows of a wired thermostat that can be programmed physically at the thermostat and through Hubitat that can fire a gas combi boiler directly? The Heltun HE-HT01 is the closest thing I could find. They state it works with electrical boilers and I have e-mailed them to ask if it can work with a gas boiler too.

If there isn't and I need to buy a boiler receiver, like the Secure Boiler Receiver HRT Gen5, then can I buy a programmable thermostat, like the Heltun one for example, forget about wiring it to the boiler and then program it directly at the thermostat or via Hubitat to in turn activate the receiver via Hubitat and turn on the boiler when needed?

Finally, in terms of the radiator valves, in the setups above how might it work? For example, with a thermostat wired to the boiler, if I turn up one of the radiator valves in one room but the thermostat is not set to heat, can the thermostat just ask like a switch to turn on the boiler without turning up the heating in the whole house? Or would I need a seperate boiler receiver to bypass the thermostat for that? Then if I turn the heating on via the thermostat, could I create rules to turn up every radiator valve with it?

Essentially I'd like to be able to programme heating and turn up the heating ad hoc in the whole house from the main thermostat, perhaps offsetting some of the temperatures around the house where some rooms heat up and retain heat better than others but also turn on the heating in 1 or 2 rooms directly without turning on the heating across the whole house if needed. I'm struggling to get my head around how it all might work.

Any advice on devices and setup would be greatly appreciated!

Thanks in advance

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So I'm about to do the same thing in the USA. Getting an IBC combi boiler. I only have 1 zone and no radiator valves. But look at Sinope, they make Zigbee thermostats that work with HE. They have many varieties for high voltage, gas fired, electric, etc. I suspect your boiler is low voltage AC (24/48volt DC) The Sinope thermostats can be directly controlled as well as through HE and via rules using various sensors and radiator valves. As far as turning on the boiler from a radiator valve, a rule can definitely handle doing that.

Sinope makes both WiFI and Zigbee, be sure to get the Zigbee model and be careful, they have about 8 versions or so.

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Thanks for the info and suggestion! From what I can see it doesn’t look like you can program their thermostats physically at the thermostats?

Good to know that a thermostat can be set by a radiator valve and I guess vice versa. I imagined that can all be set with rules but until I try it it’s hard to picture.

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I've used Honeywell, Nest, Ecobee and not a one of them are fun/easy to program at the device, it actually is much more difficult. Curious why would you need to be reprogramming at the device? Typically the program is set and left, and using temporary override occasionally to raise or lower. With a smart thermostat, HE and presence detection you could never need to touch it again.

I don't know if they sell Ecobee in your country, but that can work and has an HE integration, but it is cloud only, and from my personal experience is not 100% reliable.

If you search these forums you'll find plenty of ideas.

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Good to know. I'm looking for something at I can program at the device primarily for my partner who won't want to go into Hubitat but also because I will likely want to fiddle with it constantly.

Unfortunately Ecobee and Honeywell z wave thermostats don't seem to have EU z wave radios. I'll be sure to scan the forum. Thanks.

I'm still left wondering how it works with a wired thermostat and TRV's. Can TRV's turn on the boiler via a thermostat? Or is a seperate receiver/relay switch needed for either the thermostat or TRV's to switch on the boiler?

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couple things, Ecobee is WiFi only. Honeywell is Z-wave and frequency is an issue by country. And yes if you have a Zigbee thermostat and Zigbee TRVs, you can, via rules tell the thermostat to heat based on TRV temp reports.
NB- we are discussing a heating system, which has to be 100% reliable, due to life safety issues, so even if you get this to work, recall that NO home automation platform is 100% reliable, and you're trusting a 100.00 device to automate a potential fire/explosion hazard. Many here have done just that, automate their heating with HE, and haven't reported issues.

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Thanks Rxich. Heltun have confirmed that their thermostat, which can be switched to EU Z Wave. I now just need to figure out if my boiler can be switched with 230 V or if I need an additional relay.

I duly note your point on reliability. It sounds like it's well tested though. I have smoke and carbon monoxide detectors if the worst were to happen.

I'm still left wondering how it will work with the radiator valves though. Let me try and explain. I want to be able to operate the heating in 2 ways. The first is to heat the whole house or at least most of the house by turning up the target temperature on the main thermostat. I'm confident that with the right rules in place I can increase the target temperatures on all of the radiator valves and hence open them in line with the target temperature on the thermostat, offsetting as a I need to. Then the valves should close as each room hits its target temperature.

The bit I am unsure about is the reverse. If I turn up the target temperature on a single radiator valve, can I set rules so that the thermostat (that is wired to the boiler) will switch on the boiler even though it's own target temperature hasn't been increased? Essentially can it act as a relay only and disregard it's own target temperature? WIth my current Tado thermostat it will only turn the boiler on if the measured temperature is less than the target temperature. Admittedly I haven't tried it with their radiator valves.

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You're welcome. And yes, you can have a rule that will turn up the temp on the thermostat, as a response to the radiator valve being adjusted. I'd include lgoic that if the TRV temperature isn't hit after a certain time period, that the override would stop and return the thermostat to previous temp(which gets stored in a variable) I'm not the most skilled at logic, but there are plenty here who can help with the logic, and variables, to make it all run smoothly.

In the thread below are folks using TRV's with webcore, but with the latest rule machine, you don't need webcore.
@mark.cockcroft seems to be in pretty deep with TRV's and automations

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Hey check this out for your TRV, it seems perfect

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