[Greenbuilding] A Solar Hot Tub

[Nick Pine]

dantonioli at earthlink.net writes:

> The tub is the storage tank.

You might think all that water would be a useful heat store, but it can't 
store any useful solar heat if it can't change temperature.

> ... a regular solar hot tub system uses a standard "swimming pool and spa" 
> sensor/control that limits the temperature to 104 degrees. When the tub 
> temp is anywhere below 104, and the temperature of the panel is higher 
> than the tub water, the pump circulates the tub water. It's one big 
> drainback system...

> You still need a conventional heater

Some people define a solar hot tub as "one with no other form of heat."

Nick