Hot water mystery

[Georgia Mike]

Because I am having some power issues I am only running the Aqua Hot on diesel to heat the water at night for showers. I turned it off after my shower around 9 pm and when I got up this morning I still had hot water. We went out and just came back at noon and the water is still very hot. I have verified the 110 and diesel is off on the Aqua Hot so where is this hot water coming from? I verified the intellitec systems appears to be working with the 110 volt switch for the Aqua hot. I press the button and hear a click and the little green light comes on  the intellitec module. 

[timaz996]

What are the outside temps where you are at? If the outside temps are in the 90's and you are running off your fresh water tank it doesn't use much of the hot glycol to heat the water.

Tim

Edited June 21, 2022 by Tim-AZ

[Georgia Mike]

We are hooked up to water not using the tank

[Old Dog]

A lot of places in the SW the water is so hot coming out of the ground you can hardly stand in it when the mixing valve is in the max cold setting. It's that time of the year?

[waterskier_1]

The Aquahot is a very efficient unit.  When you run it on diesel (or electric - that just takes much longer) it heats a boiler full of "antifreeze" or "boiler coolant".  That the coolant that circulates through your coach to provide heat at the "cozie" registers.  There is gallons of the boiler coolant in the system, depending on which model Aquahot you have.  Since you are not likely heating the coach, there is a lot of this boiler antifreeze in the Aquahot boiler.  There is a "loop" heat exchanger for your domestic hot what that encircles (either inside the actual boiler or outside, again depending on the model Aquahot) that "exchanges the stored heat in the boiler coolant to the domestic water as it flows through the heat exchanger.  If you are not using lots of hot water, you could have hot water for days.

It is not likely due to the incoming water temperature, which varies little between summer and winter, unless the whole source is above ground (which might be heated some in the summer and freeze in the winter).

Hope this helps.

  -Rick N. 

[Guest Ray Davis]

Do you by chance have your elect engine block heater on?   Easy to tell by feeling of the engine.   My engine heats my Aqua-Hot and it will heat the engine as well.  

[timaz996]

We spent our last summer in 2018 in Mesa, AZ and the "cold" water was too hot to shower with. We had to use the park showers.

Tim

[waterskier_1]

6 hours ago, Ray Davis said:

Do you by chance have your elect engine block heater on?   Easy to tell by feeling of the engine.   My engine heats my Aqua-Hot and it will heat the engine as well.  

Not when you are parked overnight, unless you leave the engine idling all night. 

 -Rick 

6 hours ago, Ray Davis said:

Do you by chance have your elect engine block heater on?   Easy to tell by feeling of the engine.   My engine heats my Aqua-Hot and it will heat the engine as well.  

 

[96 EVO]

Boiler tank is fairly well insulated. Boiler fluid will stay hot for some time. When that gal or so that has been sitting in the fresh water loop submerged in hot boiler fluid for hours hits your faucet, it will be fairly hot for several seconds.