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Any plumbers on here?
 
            
                
                    robroy                
                
                    Posts: 4,451                
            
                        
            
                    Quick question. I have a combi boiler and don’t have an issue all over my house with the water and heat. However, in the main bathroom upstairs the bath just does not run hot and is luke warm at best, the water also comes out cloudy for most of the time. The rest of the house is fine. 
                    I believe the pipes up stairs are old compared to the new extension and boiler.
Not sure why it’s cloudy.
cheers
                Not sure why it’s cloudy.
cheers
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            Comments
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            The water from combi boilers is heated directly from the mains, so the only time the water is released to the atmosphere is when it comes out of the tap. This means that during heating, the calcium bi-carbonate present in the water changes to calcium carbonate. This causes the creation of Carbon Dioxide which close up is seen as millions of bubbles, this is not sediment it's merely cosmetic. If you run some hot water into a glass and let it cool it will slowly clear. This phenomenon is more apparent in hard water areas and from models with perhaps slower and/or lower flow rates.
 https://www.worcester-bosch.co.uk/support/troubleshooting/faqs/all-faqs/why-is-the-hot-water-produced-by-my-combi-boiler-sometimes-cloudy
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 Thanks mate, do we know why it’s only luke warm in the bath and very hot in all other hot taps?Big_Bad_World said:The water from combi boilers is heated directly from the mains, so the only time the water is released to the atmosphere is when it comes out of the tap. This means that during heating, the calcium bi-carbonate present in the water changes to calcium carbonate. This causes the creation of Carbon Dioxide which close up is seen as millions of bubbles, this is not sediment it's merely cosmetic. If you run some hot water into a glass and let it cool it will slowly clear. This phenomenon is more apparent in hard water areas and from models with perhaps slower and/or lower flow rates.
 https://www.worcester-bosch.co.uk/support/troubleshooting/faqs/all-faqs/why-is-the-hot-water-produced-by-my-combi-boiler-sometimes-cloudy0
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 Have you tried running the tap at a lesser flow rate rather than full on. The water temperature is a reflection of how much water is passing through the heat exchanger, if it’s too fast it won’t have time to heat up properly. Try running hot tap at half volume.robroy said:
 Thanks mate, do we know why it’s only luke warm in the bath and very hot in all other hot taps?Big_Bad_World said:The water from combi boilers is heated directly from the mains, so the only time the water is released to the atmosphere is when it comes out of the tap. This means that during heating, the calcium bi-carbonate present in the water changes to calcium carbonate. This causes the creation of Carbon Dioxide which close up is seen as millions of bubbles, this is not sediment it's merely cosmetic. If you run some hot water into a glass and let it cool it will slowly clear. This phenomenon is more apparent in hard water areas and from models with perhaps slower and/or lower flow rates.
 https://www.worcester-bosch.co.uk/support/troubleshooting/faqs/all-faqs/why-is-the-hot-water-produced-by-my-combi-boiler-sometimes-cloudy0
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 I had that. I found out the pressure wasn't high enough to pump the hot water around when the taps for the bath when fully opened. When I half-opened them then it would come out boiling.robroy said:
 Thanks mate, do we know why it’s only luke warm in the bath and very hot in all other hot taps?Big_Bad_World said:The water from combi boilers is heated directly from the mains, so the only time the water is released to the atmosphere is when it comes out of the tap. This means that during heating, the calcium bi-carbonate present in the water changes to calcium carbonate. This causes the creation of Carbon Dioxide which close up is seen as millions of bubbles, this is not sediment it's merely cosmetic. If you run some hot water into a glass and let it cool it will slowly clear. This phenomenon is more apparent in hard water areas and from models with perhaps slower and/or lower flow rates.
 https://www.worcester-bosch.co.uk/support/troubleshooting/faqs/all-faqs/why-is-the-hot-water-produced-by-my-combi-boiler-sometimes-cloudy
 It just meant if I wanted to have a bath I'd have to start running it three days before. ;-)0
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 If you've got a TMV fitted under your bath (most newer installations do as I believe they are part of building regs now when fitting a new boiler) then that may well be the reason. They are, apparently, self adjustable but I wouldn't know where to start. EDIT: although reading up it seems quite simple.robroy said:
 Thanks mate, do we know why it’s only luke warm in the bath and very hot in all other hot taps?Big_Bad_World said:The water from combi boilers is heated directly from the mains, so the only time the water is released to the atmosphere is when it comes out of the tap. This means that during heating, the calcium bi-carbonate present in the water changes to calcium carbonate. This causes the creation of Carbon Dioxide which close up is seen as millions of bubbles, this is not sediment it's merely cosmetic. If you run some hot water into a glass and let it cool it will slowly clear. This phenomenon is more apparent in hard water areas and from models with perhaps slower and/or lower flow rates.
 https://www.worcester-bosch.co.uk/support/troubleshooting/faqs/all-faqs/why-is-the-hot-water-produced-by-my-combi-boiler-sometimes-cloudy
 Believe this is an American site (continued use of faucet is the give-away) but covers some potential solutions if not the TMV:
 https://homeguides.sfgate.com/would-cause-bathroom-not-hot-water-tub-only-91662.html
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            Thanks all, I’ve tried the tap on half open and it’s still warm. Just annoying when trying to run a bath for the toddler0
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 And you lot call us anoraks.Big_Bad_World said:The water from combi boilers is heated directly from the mains, so the only time the water is released to the atmosphere is when it comes out of the tap. This means that during heating, the calcium bi-carbonate present in the water changes to calcium carbonate. This causes the creation of Carbon Dioxide which close up is seen as millions of bubbles, this is not sediment it's merely cosmetic. If you run some hot water into a glass and let it cool it will slowly clear. This phenomenon is more apparent in hard water areas and from models with perhaps slower and/or lower flow rates.
 https://www.worcester-bosch.co.uk/support/troubleshooting/faqs/all-faqs/why-is-the-hot-water-produced-by-my-combi-boiler-sometimes-cloudy4
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 I've got a masters in Googleology.AddicksAddict said:
 And you lot call us anoraks.Big_Bad_World said:The water from combi boilers is heated directly from the mains, so the only time the water is released to the atmosphere is when it comes out of the tap. This means that during heating, the calcium bi-carbonate present in the water changes to calcium carbonate. This causes the creation of Carbon Dioxide which close up is seen as millions of bubbles, this is not sediment it's merely cosmetic. If you run some hot water into a glass and let it cool it will slowly clear. This phenomenon is more apparent in hard water areas and from models with perhaps slower and/or lower flow rates.
 https://www.worcester-bosch.co.uk/support/troubleshooting/faqs/all-faqs/why-is-the-hot-water-produced-by-my-combi-boiler-sometimes-cloudy2
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            Quick question how come a bricklayer can lay bricks but a plumber cannot lay plumbs?.1
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 Wouldn't the profession need to be called a 'Plumblayer'?Indianaaddick said:Quick question how come a bricklayer can lay bricks but a plumber cannot lay plumbs?.3
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            To answer the original question.Probably.0
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            Can be alot of things, domestic heat exchanger in boiler , flow rate to high for boiler model , are the taps thermostatic ? , you will find the bath is normally the issue as bigger taps = more flow plus we tend to run longer than a sink so we notice.
 This week i went yo a job that had same issue and 6 other visits from various work buddies, they all missed the problem. It was the shower mixer, cold water backing through the hot and cooling it down. Just try to turn any mixers in your house to fully hot and then try the bath. Easy test. My hunch would be the heat exchanger tho. Good luck2
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            I once called my plumber Neil a "plumber". He got all tetchy and explained he was a "heating, ventilation and air conditioning engineer" not a "plumber".0






