How to take thermostatic valve off ?

[juco]

I have loosened the plastic knurled nut at the bottom and was expecting the valve to lift off, it doesnt, it feels like something is still holding it and I dont want to force it.
Nothing wrong with it I just want it off to clean it up (remove paint)
Advice please.

 

[Madrab]

It clips over a ridge that's on the valve at the bottom of that plastic thread, if you lean it over gently but firmly whilst pulling it up it should pop off.

 

[juco]

Thank you Madrab, now sorted.