### Hot water by tank versus circulating pump

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A couple of threads down someone asked about how efficient a hot water tank under the kitchen sink would be. I would like to know how the hot water tank under the kitchen sink would compare to a circulating pump hooked up on the hot side at the big hot water tank? I've ran electricity to the pumps before, most are 110v, but not sure of the current draw. Also not sure of the amperage of a small hot water tank under the kitchen sink.

-- r.h. in okla. (rhays@sstelco.com), January 24, 2002

That info should be posted on a decal on the heater.

-- mitch hearn (moopups@citlink.net), January 24, 2002.

a 2.5 gallon unit under the sink can draw @ 120 volts 12.5 amps which is approx 1500 watts which a # 12 wire can carry. The recovery rate of this typical unit is 6 gallons per HOUR. Not much recovery..just enough to wash up, shave etc. I don't think it would do good in a kitchen for example. Sells for \$140 +-

Now they make tankless in all combinations of outputs but: Cost starts at \$700 each and can range from 14KW to 22KW for the brand I was looking at. That is a 240 volts and draws anywhere from 30 amps to 50 amps. 30 amps is = dryer wire and 50 amps is = to a range (free standing) or #10 and #6 wire not accounting for any long runs you may have to compensate for voltage drop. "They" claim the tankless can provide enough water for two people to shower at one time. I haven't seen one and I don't sell them just giving info .

As far as a pump to circulate the water from the tank: If you leave the pump running (which is what you want to do to keep the water hot) it will generate pipe losses of heat and run your bill up. Thus why these folks came out with the tankless. It only runs when you need water. You could insulate the pipes with the tank; however, I feel that cost could be off set by just placing a water heater to the area of most hot water needs. In some cases, it may be best to use two water heaters to accomplish this.

Good Luck....hope this helps..

-- milam gerick (milamgerick@juno.com), January 24, 2002.