Elco Thision L - Relay + Valves on same boiler different circuit

[Sdke]

Hello everyone!

I am currently using an Netatmo Thermostat for my floor heating (downstairs). The relay is connected on the boiler on 1 circuit.

I am also using 5 valves (upstairs) connected on a 2nd circuit. I've used a small piece of cable to connect it.

The cable's in the red box is to have the boiler on for the upstairs relay.
The cable's in the yellow box is for the relay (downstairs)



Is this correct?
Everything works, just veryfing.

[GEORGzer]

For exact advice we‘d need boiler brand and type.

[Sdke]

It's an Elco Thision L

[GEORGzer]

Ok, I‘ll dig around a bit.

But I have more questions:
Do you mean Netatmo Valves that are connected to your Netatmo Thermostat?
Do you want the Thermostat to control both circuits simultaneously?

Right now circuit 1 will always be on.

[Sdke]

The valves are not connected with the Netatmo thermostat relay.

I bougth a Netatmo Thermostat, Netatmo Starter Kit (2 valves and relay) and 3 Valves.

[GEORGzer]

I‘m sorry but I now studied all available manuals in 2 languages and I can‘t really find any mentioning of connecting or room thermostat or 2 separate circuits.
Only clue I discovered are 2 terminals marked 11 and 16 that should have been bridged, leading to the X18 connector on the board. This might be the one to connect a thermostat to instead of the bridge.

[Sdke]

Yeah, everything works. But it would be nice to not have the 2nd circuit (with the valves) always on. A second relay could fix it, but you just can't buy these solo..

Is it an option to split the cable of the current relay?

So I have 2 black and 2 gray? 1 black gray in the 1st circuit and 1 black gray for the 2nd?

So when a valve is open, both circuits will work but that's no problem for the floor heating and vica versa?

An other idea is to use my old thermostate and put on Manual mode. It's a Honeywell cm927. So when the Smart Valve's open the boiler goes on?

[GEORGzer]

The best way would be to buy another Thermostat and pair all Valves to it.

I wouldn’t recommend splitting both the black and the grey wires and it shouldn’t be necessary.
The way those control-contacts usually work on boilers is that one terminal provides a low current (10v in common) and if that currency finds its way to the other terminal, the boiler switches on.
With 2 circles, both will most likely carry the same current, so connecting them by accident wouldn’t be the end of the world.
It would be better to determine which terminals are the live ones with a voltmeter, connect the black wire to one of them and then either split the grey wire before or connect it to the second terminal of that circuit and add a bridge wire to the one terminal of the 2nd circuit, that is not carrying any current.

If we could find the correct manual, the wire diagram would answer that question. Maybe look for a specific model number or share a photo of the label.


I would invest in a second thermostat as it is the only way to avoid a zone being active when it’s not necessary.