Switch from 2-wire mechanical thermostat to Meross MTS200

[Hoshi]

Hi guys, I want to replace my 2-wires mechanical thermostat with Meross MTS 200.
On the picture of mechanical one, the left wire is N, right one is L.
I tried to connect wires to Meross as on picture, thermostat displays data, and I hear "click" sound when it wanted to turn on the heating, but the radiators remains cold. What I did wrong? Any advise will be appreciated.

 

[ericmark]

Wires go to 4 and 5. And you need to install extra wires to power the thermostat, or select a battery powered one.

 

[Hoshi]

Ops, in this case I need to return the Meross to Amazon maybe. Thanks!
However I've found the yellow wire not connected to anything. I guess it won't help in my case?

 

[CBW]

Ops, in this case I need to return the Meross to Amazon maybe. Thanks!
However I've found the yellow wire not connected to anything. I guess it won't help in my case?

Colours usually mean feck all in a heating system, so if it’s traceable and can be connected to Neutral at both ends, you might be able to get it to work.