I recall a demand based pump from 20 years or so ago. It was
attached between the hot & cold lines at the farthest point of use
from the water heater. When a sensor detected a drop in the hot
line pressure the pump would turn on and pump from the hot line
into the cold line until another sensor detected that the hot line temp
was up to some setpoint. The thing was fully automatic, no timers, no
manual switches, and would trigger if any hot faucet was momentarily
turned on.
I can't remember the name or manufacturer. Googling is left as an
exercise for the OP.
Art


"Dave, I can't do that" wrote
Thanks for th thoughts...

Dave, that is no different to running the tap other than it will
happen faster. I would still be putting a slug of hot water between
the water heater and the tap. The only thing is I would not be wasting
the water and that is not a huge concern with a well.

Looks like back to plan A, run the tap. grin

Dave