HW Heater as storage tank?

[MaxBlack]

Been thinking about our ice cold well water and that we don't (directly) drink it, we have mixers at toilets to minimize sweating, and it seems it has to increase our hot water usage though of course valves should take care of that.

Our equipment room is warm in the winter owing to the HW heater and boiler and pipes, and so I'm thinking Why Not: set-up a WH after the pressure tank that is not connected to gas or electric. It's just a storage tank now. The water leaving it for the real HW heater and the CW lines in the house is from a 40 or 50 gallon tank that has been sitting in a warm place thus the "cold water" is no longer ice cold.

Are there any downsides to this other than e.g. sediment I'd have to keep-up after or ???

FWIW our drinking water is from our RO system at the kit sink, or from bottled water we buy at the grocery store. So the only issue with "tepid cold" is tooth-brushing which is no issue at all.

 

[Valveman]

A water heater is well insulated, so the water may not warm up for a long time. A single wall metal tank would be best to warm the water to room temp. A coil of poly pipe would probably have more surface area than a tank and work even better.

 

[Sponsor]

 

[MaxBlack]

Thanks Cary, I thought first "water heater" because it seemed to have the right in-out "flow" and of course the drain. Where does one get a single-wall metal tank that's as cheap and "ready-to-go".

The coiled pipe sounds reasonable until I think of containing it. I do have some extra space in my room but not an awful lot.

 

[Valveman]

An old water heater would work if you skin it down to the tank. A galvanized, epoxy, or glass lined pressure tank would work. Or a couple hundred feet of 1" poly pipe in a coil could be hung from the ceiling where there is the most heat?

 

[MaxBlack]

I think that is what I will look for, an old HW heater. Thanks for helping.

 

[Reach4]

The poly pipe would never rust out. An old WH run without a softener can have a lot of accumulated hardness material.

https://www.menards.com/main/search.html?sf_categoryHierarchy=&search=sidr+

 

[MaxBlack]

You're right Reach4. I will think more on "potable pipe" and try to figure-out how I might set it up. It will weigh quite an awful lot when filled with water and so support will be critical.

 

[Reach4]

You're right Reach4. I will think more on "potable pipe" and try to figure-out how I might set it up. It will weigh quite an awful lot when filled with water and so support will be critical.

One inch SIDR pipe is a little over an inch, but 200 ft of water is probably still under 80 lbs on top of the empty pipe weight. https://www.engineeringtoolbox.com/pipe-water-content-volume-weight-d_1734.html

 

[MaxBlack]

Hmm, for 1" pipe I get 0.041g/ft x 200 ft = 8.2 gallons.

 

[Reach4]

https://interstateplastic.com/catalog/pipe_for_fittings has IDs for various sizes.

 

[Valveman]

1" poly in 160# full of water weighs 0.64 pounds per foot.

 

[wwhitney]

If you want to use a coil of plastic pipe, you should know the maximum water flow rate you'd want for your house hold. For example, per https://www.engineeringtoolbox.com/hazen-williams-water-d_797.html 10 gpm through 100' of PE pipe with a 1" ID will cause a 3.4 psi pressure drop, which seems OK. But 20 gpm would cause 12.4 psi pressure drop, which sounds like enough that you'd want to increase the pipe size.

Cheers, Wayne

 

[Bannerman]

While a non functioning water heater could be used to coil the plastic pipe around, the coil height would be limited to the height of the heater.

An alternate structure to coil the pipe around could be 3 or 4 wood 4X4s which are spaced apart but running from floor to ceiling. While the coil could be made almost any diameter, it will need to be large enough to prevent the pipe from kinking. The vacant space inside the coil will provide additional surface area to absorb heat, particularly if the coil is lifted a short distance above the floor to allow air circulation from top to bottom.

It would seem the most benefit would be to add heat to only the flow supplying the WH, not to the cold water running to fixtures, although you mentioned feeding tempered water to toilets due to sweating. Are the toilet tanks not lined with foam insulation?

 

[Reach4]

If you want to use a coil of plastic pipe, you should know the maximum water flow rate you'd want for your house hold.

It's unusual for a house, excluding outdoor use, to use more than 10 gpm.

Many softeners record peak gpm between regens.

 

[Greenmonster123]

I second the poly pipe option. We have used it to heat water for an outdoor shower at a beach house. They only had cold line run out to the shed where they kept beach toys, kayaks, etc. we put a roll of black poly on the roof in the direct sun and fed it to the shower. Worked great, 100 degree water at least. As far as containing the pipe, don’t even cut the ties on the roll, just connect to the two ends as is.

 

[Jeff H Young]

It is like adding 200 foot to your water service length, perhaps worth thinking about of cource upping the size will reduce friction and increase storage cappacity. If you have volume issues now they wont be improving.
Any estimate on how much money this saving might be ? 1 dollar a month 10 , 20 bucks, or a comfort issue as well water being so cold in winter

 

[Greenmonster123]

It is like adding 200 foot to your water service length, perhaps worth thinking about of cource upping the size will reduce friction and increase storage cappacity. If you have volume issues now they wont be improving.
Any estimate on how much money this saving might be ? 1 dollar a month 10 , 20 bucks, or a comfort issue as well water being so cold in winter

I don’t think he will save anything it would only be a comfort thing. In fact he is adding to his heating load by bringing extra cold water into a conditioned space.

 

[Jeff H Young]

I see mainly comfort. I like the coil idea best