How to control "Dutch style" heating unit combined with smart TRV radiator valves?

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Hi,

Question about Dutch heating systems.

In Holland, it’s typical to have a central unit that heats water and make it flow through all the radiators in the house to heat the rooms. A single thermostat in the livingroom turns the heater on/off based on the livingroom temperature.
So basically when the living room temperature drops below the setpoint, it turns on the heating in the entire house.

I’d like to replace the dumb radiator valves in all rooms by electric “smart” ones like Moes, so I can set the temperature per room. However, then I still have the problem that the central heating unit will not turn on until the livingroom temperature drops below the livingroom setpoint. So if the living room is warm enough, and the bedroom isn’t. It won’t heat the bedroom.

How does the Dutch community (or others with similar heating systems) handle this?
I thought of replacing the livingroom thermostat by an ESPHome relay. And make an automation in HA like “if any room is colder than that rooms setpoint, turn on. Otherwise, turn off”.

The downside of this proposed system is that if HA crashes, fails or freezes, I lose the ability to heat my house.

Is this the way, or am I overlooking a more obvious solution that can still work without HA controlling it?

Thanks!

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Common in NL are two different thermostat systems. A simple ON/OFF thermostat and an OpenTherm thermostat.

If it’s OpenTherm, it comunicates a lot with your central unit and can’t be replaced easily. The replacing thermostat has to be OpenTherm compatible. So here your ESP would not help that much.

If it is an ON/OFF system, you can place the ESP relay parallel to the existing thermostat. Both then would be able to control the central unit, when they decide to do so.

BUT! You have to make sure, that when the central unit runs, there always must be at least one radiator open, better two. The central units do not like to run against closed valves. And I mean really not like. They die quiet fast… :wink:

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“place the ESP relay parallel to the existing thermostat”

See, this is the “obvious solution” I was overlooking. xD
Thanks!

I don’t think I’m adding extra risk, since the “all radiators closed and pump on” risk is the same in the current situation.

The current thermostat is an old one (20 years). I can hear the relay click when it turns on and off, so I guess opentherm protocol is surely not the case. So adding an extra esphome relay should be fine.

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I have the same question as Istria1704.

Situation.
Living room

  • Thermostat
  • Radiator with a TRV

Sleeping room

  • Radiator with a TRV

I am looking for a script that does the following.
If the desired temperature in sleeping room is lower then setpoint for thermostat living room, increase set point thermostat untill sleeping room is heated

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So both TRV valves and the thermostat in the living room are “smart” ones? All 3 connected to HA?

Or are the TRV valves “dumb” mechanical ones and the thermostat is HA connected?

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everything is smart. I use a rooted Toon and two Z-wave TRV-s

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Is the rooted Toon integrated as a “climate” thingy in HA?

If so, you could make 2 automations:

  1. If bedroom temp is lower than bedroom setpoint, set Toon setpoint to 30C.
  2. If bedroom temp is higher than bedroom setpoint, set Toon setpoint to 19C (or whatever you want).

Something like that?

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And, the native Toon integration from HA, which does work fine with non rooted, has also a climate device.