Reliance TMV locking position problem

[DeadJoe]

I have a thermal store with a 'Reliance' brand TMV. I adjusted it the other day (by twisting the blue control knob back a notch from 6 to 5) because the water seemed to be a bit hot. But it has readjusted itself back up to maximum. It seems to have loosened up a bit - if I wait and watch it, I can see it turning back all on its own. There's a ring behind the knob, that looks like a locking ring, with the pointer embossed into it which shows you what number you have selected - but it doesn't seem to do anything regardless of whether it is pulled tight against the back of the knob, or away from it. Does anyone know how to lock these things?

Thanks!

 

[DeadJoe]

Never mind... I worked it out. Remove the screw holding the blue adjuster on, remove the collar and replace the adjuster without the screw. Set the water temperature. Then remove the adjuster again and replace the collar with the little slot at the front. Then replace the adjuster, making sure to slide the locating lugs over the slot on the collar (which locks it). Then replace the screw.