Any Plumbers Here? Question re: Shower Control

[kaneohe]

We have a shower control something like this: Ecostat - S Thermostatic Trim with Volume Control | Hansgrohe US

with a knob/handle that rotates to control the temperature and a push/pull rod that diverts the water between shower head/lower spout (the latter is different than in the picture shown). Is it normal for there to be some flex/"slop" in the
position of that temperature control knob/handle?.....that is to say, if I hold that knob between thumb and first finger at 9 o'clock and 3 o'clock should I be able to wiggle that knob side-to-side a bit or should it be perfectly rigid?
I normally just rotate the handle but something in how that movement occurred motivated me to try that side-to-side test. Hopefully those words paint enough of a picture to convey the question.

 

[soupcxan]

We have a couple of new handsgrohe boxes like that and there is very little play in the temperature control knobs. Maybe 1mm, 2mm at most. Have you tried tightening the screw that holds the knob on to the fixture? Could just be loose; I'd start there.

 

[Peter]

We have exactly that control. There isn't any play on either knob. As soupcxan says, it's worth trying to tighten the grubscrew with an Allen key. 2mm and 2.5mm on ours, for the small and large knobs, respectively.

One possible gotcha. The grubscrews may be capped with blank inserts. It wasn't clear to me how you would ever remove those, so I left them out.

 

[kaneohe]

Thanks, soupcxan and Peter, for your helpful replies. Additionally thanks to Peter for mentioning the metric nature which I wouldn't have thought about.
I thought I had a metric set but when I couldn't find it, I thought I might have been thinking metric wrenches . I finally did find the metric allen wrenches hidden behind some other stuff so thanks for that side benefit.

I couldn't budge the allen setscrews either in or out.....suspect they're frozen from all the mineral deposits from the water for many yrs (tho I didn't really try to muscle it).....but the play still seems to me to be in whatever the handle is hanging onto , rather than the handle itself. It is not huge but I would have thought there would be no play at all.

 

[soupcxan]

Throw some penetrating oil into the stuck screw and let it work, then try again. I'd be surprised if it can't be fixed with a little tightening.