Plumbing help needed Please

[Mike]

Hi all

Hope someone can help on this issue.

I have a combi bolier and noticed the water temperature from the bath tap is not a warm as the water coming from other taps. Could not have a bath in it (to cold)

Don't want to turn the temp up as water would be to hot else where.

Any ideas on why this is happening ?

Many thanks for your advice and time

Regards

Mike

[Chris]

Possibly an excessively long run of pipes to the bath compared with the other taps? Also sometimes (though not always) with a combi boiler, the more you open up the hot tap, the cooler the water coming from it will be. You could try not opening the hot tap so much. It will take longer to fill the bath but the water may be hotter as a result.

[Mike]

Originally Posted by Chris

Possibly an excessively long run of pipes to the bath compared with the other taps? Also sometimes (though not always) with a combi boiler, the more you open up the hot tap, the cooler the water coming from it will be. You could try not opening the hot tap so much. It will take longer to fill the bath but the water may be hotter as a result.

Not sure on this as the feed to the bath is shorter than the kitchen which is fine.

Many thanks

Mike

[Chris]

Try part-opening the tap then - my in-laws' combi system does the-faster-the-cooler, it drives me mad. Older systems seem to control the flow to ensure hot water is always hot, I don't know why this has changed.

[martyh]

if you can tell us the location of the boiler in relation to the bath ,also does the combi heat a tank or is it direct heat ?
is this a persistant problem or has it just started?

[Osem]

Has this only just started to happen or have you had this problem before? The temperature of the hot water will depend to an extent on the flow rate from the taps, the thermostat setting on the boiler and of course the temperature of the incoming mains water. You'd normally run a bath at a much faster rate than you'd need at the basin taps so I'd expect the bath water to be a bit cooler. Now the weather's so much colder, it could well be that the boiler setting is too low to cope with that flow rate and the colder incoming mains, hence a cold bath. As has been said, slowing the flow rate by partially closing the bath tap will cause the water to get hotter. If this doesn't do the trick, I'd experiment a little with the boiler setting and see what effect that has.

[martyh]

Originally Posted by Osem

Has this only just started to happen or have you had this problem before? The temperature of the hot water will depend to an extent on the flow rate from the taps, the thermostat setting on the boiler and of course the temperature of the incoming mains water. You'd normally run a bath at a much faster rate than you'd need at the basin taps so I'd expect the bath water to be a bit cooler. Now the weather's so much colder, it could well be that the boiler setting is too low to cope with that flow rate and the colder incoming mains, hence a cold bath. As has been said, slowing the flow rate by partially closing the bath tap will cause the water to get hotter. If this doesn't do the trick, I'd experiment a little with the boiler setting and see what effect that has.

yep ,that's what i was leading up to .It is a common problem this time of year when there has been a drop in tempereture in mains water

[Mick Fisher]

Combi's often suffer from sub standard installation practices.

Most common is under sizing of the Gas supply pipework. This can manifest itself as underheating the hot water side during cold snaps. Good practice is to keep 15mm tube to the absolute minimum and depending on distance from the meter and the size of the boiler running the gas supply in 22mm and/or 28mm tube.

Whatever, you need the problem investigating by a qualified, registered, reliable, experienced and honest contractor.

However quite where you might find one of these mythical characters is completely beyond me.

[Mick Fisher]