Plumbing in the Home/Hot Water Heater


I recently had a new thermostat installed in my 50 gal electric water heater.  
When the thermostat is activated I get scorching hot water but a few hours later
that water temperature has dropped and by next day the water is barely warm.  
When I re-set the thermostat the same process repeats itself.  This happened
with the old thermostat and I thought that installing a new one would solve the
problem.  The heater is nine years old.  Do I need a new one?  If not, what
might be the problem.

John, Electric water heaters of the size you have use a dual element system.  they are usually 4500 watt are designed to operate in series. The top element fires first to heat the upper 1/3 or so of water then when temp. is reached, the lower element fires to heat the rest up to temp. This arrangement give you a small amount of hot water quickly. Both are controlled by a mater thermostat located at the top element. Some brands also have a small thermostat on the lower  element that will control the  lower portion as well. By your description, I believe the lower element is shot. At nine yrs.old, I would change both elements. That should solve your problem. Side note: 99.9% of the time it is always recommended to change both elements at the same time regardless if only one is bad.


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Jay Nicholas


Plumbing & Heating (warm air, hot water & steam heat)


40 years in the business, 35 years as a lic. master plumber in NY State. Retired

Graduated Magna cum laude at the School of Hard Knocks

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Commercial, residential and light industrial. You name it ...I have probably worked on it

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