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hot water takes too long

We had a tankless water heater installed about 1 1/2 years ago. It takes probably 2 gallons or more of cold water going down the drain before we get hot water anywhere in the house (bathroom sink, kitchen, shower etc).
I have seen Richard installing something under a bathroom sink that 'bypasses?' the cold water back into the cold water pipe which lets the warm water come through almost instantly. To engage this action the person had to push an electrical(?) button which was installed on the side of the cabinet.
I would like to show this to a plumber, but cannot find the video on this website. Can somebody provide a link?

Re: hot water takes too long

I think you are asking about a "demand pump".

Re: hot water takes too long

This may be what you're thinking about. I don't think they will work without a tank.


Re: hot water takes too long

I saw the episode years ago. I think one of these is what you're looking for:



I don't know just what exact product Richard used, but these works the same way. Install under the sink furthest from the water heater, plumb into the existing hot & cold water lines. The pump also needs power; if there is an outlet above the vanity, you may be able to fish a wire through the wall from that outlet into a new outlet in the vanity cabinet.

When you push the button, the pump is activated and it draws cooled-off water from the hot line and backfeeds it into the cold line until the hot water reaches the pump, at which time it turns off.

(P.S. -- You may notice some similar but less expensive options. Those other options are the pumps only; they don't include the plumbing kit which you'll need in order to hook it up.)

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