Tepid bath - plumber or electrician?

[WinifredBanks]

I can no longer get very hot water out of our bath taps; do I need an electrician to look at the thermostat on the bath and the boiler, or a plumber?

Thanks

is it a combi boiler?

Does the basin tap run more hot than the bath tap?

Thanks PigletJohn, it is a combi-boiler, and I think that the basin tap does run more hot than the bath tap

Make sure. Is the basin hot tap fully hot?

Also, feel the pipes coming out of the boiler (or look in the manual) and identify the 22mm flow and return for the radiators, and the 15mm pipe for the hot taps.

Has someone fiddled with the temp dial for your water on the boiler?

Thanks, I will have a look when I'm back from work.

Well my husband is an electrician, and we have the same problem - he's clueless
So I would say plumber, but subbing to hear others thoughts!

I am by no way an expert...however I had this v same problem with my combi boiler a couple of weeks ago. Water taps in bathroom was red hot. Called a plumber, who basically said I had my taps turned up too high & altered it to a slow flow & hey presto the water was red hot! It takes an age to run a bath, however it is red hot.

Something to do with width of pipes & cold weather.....

I have this problem if I have the taps on full whack. Try turning them right down?

Ooh I have this but it's my shower too. I can get hot water to the shower if I run the cold tap on the sink though. I'll stick around and see what advice you get then steal it if you don't mind!

yes, that's one of the causes, if you have a combi boiler. It can be verified by comparing the (small) basin tap temperature with the (large) bath tap temperature.

In summer the incoming water is about 10C warmer, so when the boiler heats it by 35 degrees above the incoming temperature, it is 10C hotter out of the taps.

sillymilly, have you got a combi boiler? If not, different cause. Do the Thumb Test.

Go to the bathroom. Turn on the basin cold tap. Put your thumb over the spout. Can you stop the flow? Now do it with the hot tap. How does it compare?

Ooh, interesting. I can stop the flow on the hot tap! Errr, what's that mean?! It is a combi boiler by the way. Sorry for the hijack by the way

and the cold?

Sorry, the cold splurted all over and I couldn't stop it. Hot was much weaker.

Aha.

Yet you say you have a combi

Are there any water tanks or cylinders in your home?

I've just double checked - the hot is def weaker and can be stopped by pressing over it. No water tanks or cylinders either. The boiler was replaced about 7 years ago and is a Worcester something or other (I am in bed now but will check tomorrow)

Someone said they thought it was possible the shower was leaking cold water into the bath pipes? I am totally clueless about plumbing, but would that be possible? I'm so sorry for the derailing of the original thread - thank you for helping me poss figure it out though.... I'd love to be able to use the bath again

if you have a combi and no tanks or cylinders it is very unusual for the hot pressure to be lower than the cold pressure. This will prevent a shower mixer from controlling the temperature.

Maybe your boiler is badly clogged with scale, or I suppose it is possible that you are in the bottom of a valley or something and the water pressure into the boiler has been reduced. In which case the pressure into the cold taps should have been reduced to match. Look for something like this between your incoming stop-cock and your boiler.

Hi PigletJohn, I finally checked, and the hot tap for the sink runs hotter than the bath hot tap. By the way, I have tried running the bath very slowly, and this does not help.

Does the bath tap have two knobs?

I have the exact same problem with the bath taps and i have a combi burner.the sink taps are hotter but still not overly hot. Downstairs sinks run so hot you cant touch the water.. Any ideas sorry for the hi-jack also does anyone know why the pressure on the burner would drop to 0 every 3 days. Thanks

We have the Worcester and our hot water is not as hot as it was. We've had this before - it's the diaphragm of the changeover valve. That's a plumbing or YouTube job.

Nona - is that the pressure on the gauge on the boiler? If so that's water pressure and goes with the diaphragm problem.

Yea its the gage on the burner.every 3 days i have to go out and put the pressure back up.its rather annoying.

you have a leak. Most likely it is at a radiator or pipe. Feel around and under them all.

Also look at the pressure relief pipe that is visible outside the house. It will be a small copper pipe curved round so that it points back at the wall. It will be coming out behind the boiler. If there are signs that it has been dripping it needs to be changed.

radiators are all dry.will have to get plumber out as all pipes from burner are underground.looked where pressure gauge was on the burner before but couldnt see anything visible.thanks for the help.