I'm probably asking for trouble with this question, but here goes….
I had tenants complaining of a luke warm shower and discovered that their boiler hot water temperature was set to about 50º.
The shower has a thermostatic valve and has no separate power control. As expected the mix was coming out about 38º. The manual says that at least +10º is required in the hot supply and that they recommend 60º. (Meaning that for a 43º shower they'll need at least 53º at the boiler, but higher in reality to get some power).
However, the bathroom sink has separate cold and hot taps (no mixer) which means they are at risk of scalding themselves. This is why they turned the boiler down.
Is there a way – without fitting an electric shower and without replacing the bathroom taps – to have the shower temperature up as required, but keep the wash basin safe?
Aside: Previously I had a thermostatic valve with a power handle, but tenants turned it up full blast and then complained it was cold. I figured prioritising the temperature was a better route as long as the power was acceptable.
Best Answer
You can install a standalone tempering valve on the line to the sink, or (probably a larger one) on the line to "everything but the shower" which would protect the kitchen sink as well, for instance.