Why RUN the water?
Now is the question above seem like a dumb question coming from me? Have any of you considered this alternatvie to water waste?
If anyone has the luck of living in a home with a basement below the kitchen and has reasonable accessd to their plumbing lines, You can avoid all the water waste by simply running a return line back to your water heater.
Yes there are recirculating pumps with fancy mixing valves that send the heated water back thru the cold water lines but you can accomplish the same effect for practically free.
If you can gain access to the piping below the dishwasher, you can run a return line from that supply line back to the hot water heater and the water in the line will be warm to hot due to the natural convection currents set up by the difference between the hot and cold water in that line.
The return line should be 1/2 the size of the supply line and go back to the heater and connect at the bottom of the heater where the drain valve is. You would have to remove the valve, install a nipple and a tee where the vavle was and then connect the return line to the tee with a check vlave in line to prevent the water from flowing from the tee back to the dishwasher.And then reconnect the drain valve. WHile you are at it, replace the plastic piece of crap the heater came with and install a 3/4" ball valve with a garden hose adapter so when you drain your heater as recommended by the manufacturer, it will now have a full flowing ball valve instead of that stupid thing it came with that has the infamous popout washer that dislodges and makes the valve leak.
Needless to say, while you are working on the HW lines, it would be wise to insulate the supply and return lines so there is less heat loss. If your setup allows it, you can also or instead, do the return line setup from the furthest sink or tub/shower back to the heater as long as the kitchen is in that loop and have the hot water ready at all points, otherwise you may have to settle with just doing it for the dishwasher/kitchen sink line.
I hd my uncle do this years ago and he hasnt complained about cold water from the hot water fasucets anymore. He ran it to the dishwasher supply and back and gained the instant hot water in his bathroom which was first in the line as his second floor tenants even benefitted from it as they were before the dishwasher too.
Guys, give it a try and let us know.
If you are on a slab.. well then you may have to go with the circulator system. They work and will accomplish the same thing but with more cost.
Even if you cannot sweat pipes, you can use the softer, flexibe copper tubing with compression fittings or even Pex if you can get it where it withstands 200 degrees. Easier to work with and can still be installed neatly by just about anyone.
