Editor, Manteca Bulletin,
I enjoyed your lead article on the Bulletin’s published Friday August 21, 2014 regarding measures being considered to improve water use efficiency in residences. Specifically, the “point of use’ or “flash” water heaters. I have a different and perhaps a better solution.
When I personally built our home in 1989 I installed a hot water re-circulating pump which results in near immediate hot water at the various faucets throughout our home.
Here is how it works. First I ran the “out put” hot water from the top of the hot water tank and ran it throughout the home, providing water as needed to various outlets and to the very last point of use ( in our case that is the master bedroom sink)....quite typical of home construction. Now here is the added feature: Rather than terminate at the sink I continued with the hot water line, up into the attic, across the house and back to the bottom of the hot water tank where I connected this extended hot water line to the bottom of the tank. Then I installed a re-circulating very low horsepower electric powered water pump “in line” in the attic with the extended water line. The pump is installed at the highest point in the closed system per instructions from the manufacturer. Essentially the hot water enters one side of the pump and out the other and continues on to the hot water tank....the point of origin.
With this system the hot water is circulated constantly through out our home resulting in near instant hot water. The hot water tank which I described has been in service for about 25 years without a problem. The reason it has lasted so long is because the water is constantly being circulated through the tank from the top and back in through the bottom thereby nearly eliminating residue build up in the bottom of the tank which is why “normal” tanks need replacing every 10 to 15 years or so.
With a bit of engineering this system can easily be retrofitted into an existing home and is a “breeze” for new construction.