Netatmo Thermostat Modulant Intelligent Installation page 18

Test the Relay
4
5
Push the relay button. The LED of the Relay will light up and
the boiler is switched on.
6 7
Push the relay button again. The LED of the Relay will turn off
to indicate the boiler is off.
See the Installation Troubleshooting p. 30 for more help.
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