Immersion stat question

dodzy

Not a problem, just picking the brains of residents here as something is bugging me. Let's say you have a top fitted 27" dual immersion element fitted. The sink element is say 1/2 the length of the bath element and the stat roughly the same length as the sink element.

So you fire up the bath switch and heat the water. Assuming that the stat is at its preset of 60C, I am guessing that when the water temp surrounding the stat sensor reaches set temp, the heater element is deactivated. If this is the case, and hot water typically rises, how is the lower portion of the tank heated when the stat is situated much higher in the tank than the lower part of the bath element?

maradonas

my brain is hurting

danjo

I assume the water is circlating in the tank. Once you heat the water on the lower half is sets up a continous circulation.

dodzy

danjo wrote: »

I assume the water is circlating in the tank. Once you heat the water on the lower half is sets up a continous circulation.

Now my brain is hurting. Why would the water be circulating?

Pete67

Convection. As you heat water it expands very slightly, so its density decreases, making it rise and float on top of colder water. This sets up a convection current. As long as you keep supplying heat this process will continue until the water boils or you remove the heat source.

engineermike

As Pete rightfully said - convection / heat and pressure moves the heat to the top of tank - circulating the water at the element position.
Also overriding or governing tank stat would be in an off set position dependent on the set up and type of hot water storage tank set up you have.
mike

dodzy

Peter/ mike - thanks to you both;)