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 No hot water in SOME faucets!
Author: Anonymous User

I hope you can help-- plumbers here say it is impossible. I get my hot water off my oil burner. In most of the house faucets we get plenty of hot water... but in the two bathrooms there's plenty of hot water when you turn on the shower, and only about 30 seconds worth when you turn on the spigot to take a bath. We are not running low on hot water as when the spigot runs cold, I can put the shower right above it on again and plenty of hot water. We also have lukewarm coming into the washing machine in the basement, and plenty of hot water in the kitchen. I have had two mixing valves changed with no improvement. The plumbers say the water is coming up from the same place and it is impossible to have hot water in the shower but not in the tub faucet. I don't mind paying a plumber but they are all incredulous... haven't a clue what is going on. Can anyone help me here--- I miss my bubble baths!!!
Thank you all!!!

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 Re: No hot water in SOME faucets!
Author: steve (CA)

Jan, there might be a problem with a single handled faucet/tub(shower) valve, that is causing the cold water to leak into the hot water piping. With the large flow from the tub spout, there might be enough of a pressure drop in the hot supply, that the higher pressured cold water is leaking over.

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 Re: No hot water in SOME faucets!
Author: e-plumber (NY)

It could also be that the water is passing through the coil (at the boiler) too fast and not being heated properly when the high flow tub spout is being used. The other fixtures you mentioned have water restrictors built in them that slows the flow of the water through the coil.

Have you contacted the oil company about this problem? If you have a service contract, they might address the problem or advise you what to do about it.

Good Luck. e-plumber


"The society which scorns excellence in Plumbing as a humble activity and tolerates shoddiness in philosophy because it is an
exalted activity will have neither good Plumbing nor good philosophy: neither its pipes nor its theories will hold water." -
John William Gardner 10/8/1912 - 2/16/2002

Repair your leaking Plumbing fixtures ASAP []
This slow drip will waste 7+ gallons of water per day.

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 Re: No hot water in SOME faucets!
Author: Anonymous User

If your mixing valve does not have integral check valves, that could be where your water is passing from cold to hot. The pressure drop will control how hot the water will become. I just had this problem on Monday. Install a swing check on the hot and cold side of the mixing valve.

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