On 26 Oct, 19:38, jgharston wrote:
Grrr. This is why I prefer proper stored hot water systems...

My shower has a mira Discovery thermostatic mixer, one of
these:http://goo.gl/0n7g

Try as I might I can't actually get the hot water to be hot.
With the temperature control turned all the way to "hot" it

It's a TMV and comes factory set to a (low) maximum temperature (43
deg or so typically) which is low enough not to cause scalding to
elderly or disabled people if installed in a care home or such. The
idea is the makers don't get sued when a numpty plumber causes
scalding to someone's granny. You can alter the maximum temperature,
usually involves taking knobs off and such. See manufacturer's
installation instructions.