On the screen I see the sign of the heat crossed with the number 1

[Xander_zs]

Hello. On the screen I see the sign of the heat crossed with the number 1, low water level. Where is it filled? With normal water? thanks.

Sorry, I don’t speak German.

[Vtxbe]

you fille with water + antifrost ; the same as in the motor.

The bottle is under the zinc, in the shower room.
The panel is only fitted with velcro and clips; no tools required to remove.

[Xander_zs]

Thank you. I've filled it up and the alarm's gone. I found also the leak in a stopcock. Thank you