On Thu, 6 Feb 2020 10:56:04 -0500, Ralph Mowery
wrote:

In article ,
says...

replying to Peabody, rdankwort wrote:
This is a very common phenomenon in water heaters. In the morning my temp. is
just warm; after I do a load of laundry it is piping hot. And in-between for
moderate use.

This doesn't make sense. It should be up to its maximum temp when no
one has used any hot water.

Not after a couple of hours.




And if you take a deep bath or very long shower, it should run out of
hot water until it has time to heat it again.

Sure, but they didn't say they were pulling a very long shower, just
a load of laundry. So, it's enough to trigger the WH to fire up and
start heating the water again.




The water will be the hottest just after the thermostat cuts off. I
don't know how much temperature variation the water heaters have, but
seems to be a lot on mine and the one I just replaced. They were both
tall and had the dual heating elements.

I did measure the temperature of my electric oven and it surprised me
how much it varied. Seems like at either 350 or 400 deg F it would
swing at least 50 or more deg low and high.

I worked on instrumentation at a large plant. We had controllers that
would hold things with in just a few degrease or less. However the
controllers were proportional and not just the 'bang bang' off and on
types. I would have thought by now the ovens would have something like
that, but I have not seen any in the common house price range.
electric and gas are totally different in operation. If it is an
electric heater he likely has one bad element.