Watts sells an instant hot water system too. Theirs has a little
pressure-boost pump that installs at the water heater, raising the hot water
pressure slightly. At any (or every) faucet you can install a thermostatic
valve that bypasses cool water back through the cold water line.
It's a fairly inexpensive system, easy to install, and it requires no return
lines.
The obvious drawbacks of this system are that the hot water lines throughout
the house or slab will always be losing heat, and the cold water lines will
be lukewarm. If you can install return lines, you can eliminate the
lukewarm cold water problem. Then again, for bathroom use, assuming that
most times someone is washing hands they've also just flushed the toilet,
the cold water will be purged anyway. In the summer warmer water in the
toilet tank will lessen tank sweating too.
You could, of course, also install a timer on the water heater pump and only
run it during the hours you want instant hot water...
Karl
|