Slow drip from shower thermostatic(?) valve

[darossi]

Hello - please forgive me if I've used the wrong terminology!

I have attached three images which show the location of this leak/drip.

The shower is connected to the wall as shown - the knob on the left is to turn the shower on and the knob on the right is to control the temperature. Where the shower is connected to the wall on the 'temperature knob' side, there's a very slow leak/drip coming out of the fixture as shown by the arrow in my photos.

Is it just a case of tightening the bolt that connects the unit to the wall, or is this likely to be something else that I should ask a professional to look at? As shown in the photo, the drip is coming from in front of the bolt rather than behind.

Many thanks for any advice!

Darossi

 

[oldbuffer]

Tighten the nut up. Spanner on nut with handle to right, push down on handle. Don't overdo it.

 

[darossi]

Thank you - will give this a go!