Why was the hot water becoming less hot in 3 to 4 days?

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Why was the hot water becoming less hot in 3 to 4 days?

Author: ericsandstone (TX)

Owner of two nearly 6 year old 50-gallon water heaters wanted to know why the hot water had become cooler and cooler over 3 to 4 days.

Went to attic, noted, and cleaned threads of water connection points. Company I work with had done the install and warranties that sort of problem.It was corrosion at connection points.

Noted that the pilot light of each water heater was out. Could see nothing obviously wrong which could have been cause of both pilot lights being out. Owner stated that he had minutely adjusted the temperature knob of the gas controls, turning the setting just a wee bit higher than the lowest setting.

I had no problem lighting the pilot lights of both and the burners kicked into life when I set the knob to just past lowest setting.

I just read that dip tube gone could contribute to less hot water. Winter season cannot be a factor right now. Lots of sediment could reduce warming of water but, that much with water heaters that young? Rheems. What other factors could produce this 3-4 days recently of cooler warm water?

Pilot outages - from thermopile or thermocouple being worn or dirty. Water in the combustion chamber. Other types of causes?

Thought it was odd for both pilots being out and that the condition was said to be water getting cooler during past 3-4 days. Possible that someone fiddled with the control knob and created the condition?

Re: Why was the hot water becoming less hot in 3 to 4 days?
Author: srloren (CA) The last sentence makes the most sense to me. Corrosion at the joints would not cause the problem.
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Re: Why was the hot water becoming less hot in 3 to 4 days?
Author: NP16 (OR) wonder what the typical life span is for a thermocouple or thermopile that is under use 24/7 ?
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Re: Why was the hot water becoming less hot in 3 to 4 days?
Author: hj (AZ) MOST of them are, and I have had heaters that were decades old without replacing the thermocouple.
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Re: Why was the hot water becoming less hot in 3 to 4 days?
Author: Paul48 (CT) Wow....6 yr old heaters with standing pilots?
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Re: Why was the hot water becoming less hot in 3 to 4 days?
Author: hj (AZ) There are MILLIONS of "6 year heaters" sold which do NOT have an electrical connection so they DO "need" a standing pilot.
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Re: Why was the hot water becoming less hot in 3 to 4 days?
Author: srloren (CA) I don't know if this is your situation but many water heaters that are installed in a cabinet on the exterior of a home can have the pilots blow out from wind....just a thought.
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Re: Why was the hot water becoming less hot in 3 to 4 days?
Author: Paul48 (CT) You're right hj…...I was jumbling boilers and water heaters.
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Re: Why was the hot water becoming less hot in 3 to 4 days?
Author: hj (AZ) Downdrafts can also cause pilot outages.
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