Lukewarm bath and shower but hot everywhere else

miccahotpants

Hello, hope someone can help.

We have a shower that runs off the bath tap and for some reason both shower and tap only put out lukewarm water. We're using a combination boiler (Worcester in the kitchen downstairs) and the bathroom sink in the same room produces hot water.

When we run the shower the boiler acts like it should firing up the pilot light but the water just isn't getting hotter.

I've seen people talk about a mixing valve but not sure if a shower off the taps even has that? Any ideas?

Le_Kirk

When you turn on the water, the boiler should fire up to main flame. If it is the type of boiler with a permanent pilot it will be just that - permanent. If it is electronic ignition, you should hear the gas valve opening (click) and then the flame will ignite. Look at the boiler with no taps turned on, what is its status, i.e. flame off/pilot on? Then turn on the kitchen tap, does main flame ignite? Is water hot? Turn kitchen tap off. Ask someone to turn on bathroom sink, does main flame ignite? Is water hot? Turn off bathroom sink tap. Turn on bath tap, does main flame ignite? Is water hot? The answer to these three test will lead us to a solution.

variable_luck

We just got a "thermostatic" shower/bath installed, initially it was the same, piping hot water out of every other tap in the house, lukewarm from the bath/shower even when turned up to max heat. Sorry I cannot be more helpful than this, but the plumber adjusted some thermostat inside the mixer and it now comes out hot, so if you have a mixer tap the problem is likely to be in there and not your boiler especially if the other taps are hot.

casper_g

Is this a new build or at least a recently installed bathroom? The 2010 building regs require a thermostatic valve on the bath to restrict the hot water to 48°C, with the aim of preventing scalding. If this valve is badly-adjusted or if you just like your water really toasty, this could be the issue.