Glow Worm boiler water temperature

[ragdalian]

Hi have a Glow Worm Ultimate boiler (2.5 years old) not able to adjust hot water temperature. When in shower or running hot water takes a while to heat up then goes scalding hot then luke warm over and over. When try to adjust temperature reading shows 50 however when attempting to alter water temperature on boiler on adjustment small screen goes blank. Any ideas.

Thanks

[gas4you]

Sure you don't mean an Ultracom?

[ragdalian]

Booklet shows Glow Worm Ultimate 30c

[gas4you]

Too new for me then.

I haven't touched a new Glow Worm and wouldn't want to.