Shower is luke warm at best

longwalks1

My shower (fed straight from combi boiler) is luke warm at best, even after its been on for 10 minutes or more, when it was fitted a few years ago it was always very hot, bit too hot to be honest. Mrsbritishboy pointed out how cold it is now (slight exaggeration) but its a lot cooler than before, I looked on the boiler and the temperature knob is turned up almost to maximum... and ideas please?

I know its due a scale inhibiting cartridge change but what else could it be?

Thanks everyone

anotherbaldrick

Assuming the shower valve is a thermostatic job it could be lime scale building up on the wax cartridge or perhaps on the inlet disc valves to the hot and cold water supplies. If you advised what make and model shower mixer it is members could advise you how to dismantle and clean it. It won't be boiler temp that is the problem or you would have noticed the drop in temp at the sink tap. The shower mixer valve will have an antiscald protection device to stop you getting water at boiler temperature.

longwalks1

Thanks baldrick
It's a Hudson reed thermostatic single arm mixer, can't remember the model so will look it up tomorrow. I live in a very very hard water area if that helps

plumb1_2

Check the filters are not blocked. Also remove the cartridge and descale.

longwalks1

Cheers people
Plumb1 when you say the filters which ones do you mean please? Have got a new combi-care scale inhibitor cartridge, looks easy enough to change, do I just turn my mains off under the sink, then run all taps that come from boiler to empty it, then swap the cartridge, leaving all taps open, then water on at mains again? Will I need to switch boiler off at the mains, or on power switch on the boiler itself?

Thanks again guys

longwalks1

Just had another luke warm shower and noticed it wasn't coming out with much force. Finished and checked the pressure gauge on the boiler, it's sitting at about 0.5 bar is that right?

southcoastrgi

that's the pressure in your heating system not the pressure coming out of your shower/taps it should be about 1 bar when cold & the boiler isn't running, however some boilers will not operate at 0.5 bar, top up the system from the filling loop & see if the temp inproves, however if your taps are ok & it's only the shower then you need to follow the advice from the other guys above.