I recently moved to an apartment where temperature of water in the shower fluctuates and we called for a plumber. He either cleaned up or replaced one part (I think it was the mixer - nothing visually changed), saying that it might because of stone buildup in the plumbing.
Unfortunately, the temperature still fluctuates (but maybe a bit less). Basically the problem is that in the middle of showering, the temperature can drop to one that is way too high or too cold (and then after maybe a minute drop back). This can happen about twice within 10 minutes.
I wonder if installing a cheap thermostatic tap would help here? My reasoning is that at the very least, it should help me avoid the temperature going too hot, am I right?