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lpkbrown
further clarification of pump

Thank you for the reply to my question. Both of the suggestions required that a return line to the hot water heater be present. I thought that there was just a pump of some sort that attached to water line and made the hot water more or less instantaneous. I seem to remember Rich T installing the pump. Is this all part of my imagination?

JLMCDANIEL
Re: further clarification of pump

This one is connected between the hot and cold under the sink http://www.chilipepperapp.com/detailed_instructions.htm However it is a demand type. That is you need to push a button, or wire a motion detector to turn it on. It runs until hot water is present. This type system will even work with tank-less water heaters.
Jack

Gray Watson
Re: further clarification of pump

Recirculating line return to the hot water vessle pump goes at the end of the return line just before the vessle (water heater).
Rich has shown this in a few shows. May be water lubricated or not. It is not always necessary to have a pump, for example a gravity return. The return piping is often done where the drainage cock is on the water heater or storage tank. To be most cost effective the hot water lines should be insulated to all but the last bit of the return piping to the hot water vessle. Proper check valves prevent back-flow and contamination. Air break required when retrofitting and retaining drainage cock. Water vessle needs vacuum break.

The other option is to have the d-mand booster heater at the fixture, this system returns the not so hot water to the system via the cold water line. It is basically an Instant Hot tankless system with cross-over flush that creates instant hot water, bypassing the cooler water in the line, until it temperature senses incoming hot water is at temperature, and dumps that lukewarm water over into your cold water lines. Means that your cold water is no longer cold and has the added distasteful symptom of concentrated minerals and possible lead concentrations from having been held and heated first in the water heater and twice the stagnet time in the plumbing lines. Intentional cross-over of hot to cold water supply when the ideal is to have none. Can create contamination issues in the potable water supply. Frowned upon by most health and environmental engineers, and more informed plumbers. Restricted in applications in many jurisdictions, if not prohibited all together. Some allow in residential single family private supply systems only.

Fencepost
Re: further clarification of pump

Gray Watson's comments imply that the hot water from your faucet is unsafe for human consumption. Hogwash.

JLMCDANIEL
Re: further clarification of pump

Not to mention an instant water heater doesn't return not so hot water to the cold side.
Jack

Gray Watson
Re: further clarification of pump
JLMCDANIEL wrote:

Not to mention an instant water heater doesn't return not so hot water to the cold side.
Jack

I said:

Gray Watson wrote:

Recirculating line return to the hot water vessle pump goes at the end of the return line just before the vessle (water heater).
Rich has shown this in a few shows. May be water lubricated or not. It is not always necessary to have a pump, for example a gravity return. The return piping is often done where the drainage cock is on the water heater or storage tank. To be most cost effective the hot water lines should be insulated to all but the last bit of the return piping to the hot water vessle. Proper check valves prevent back-flow and contamination. Air break required when retrofitting and retaining drainage cock. Water vessle needs vacuum break.

The other option is to have the d-mand booster heater at the fixture, this system returns the not so hot water to the system via the cold water line. It is basically an Instant Hot tankless system with cross-over flush that creates instant hot water, bypassing the cooler water in the line, until it temperature senses incoming hot water is at temperature, and dumps that lukewarm water over into your cold water lines. Means that your cold water is no longer cold and has the added distasteful symptom of concentrated minerals and possible lead concentrations from having been held and heated first in the water heater and twice the stagnet time in the plumbing lines. Intentional cross-over of hot to cold water supply when the ideal is to have none. Can create contamination issues in the potable water supply. Frowned upon by most health and environmental engineers, and more informed plumbers. Restricted in applications in many jurisdictions, if not prohibited all together. Some allow in residential single family private supply systems only.

A metlund or d'mand water heater. :rolleyes: @ Jack! Your chillipepper is cheap knock off that does exactly that. Cross over and dumps the lukewarm water into the cold water line.

Of course they bypass/return the lukewarm water via the cold water line.
http://www.tanklesswaters.com/product.asp?product=S-70T-PF
http://www1.eere.energy.gov/inventions/pdfs/act.pdf
http://www.tanklesswaterheaters.com/dmandsystems1.html
http://www.taco-hvac.com/track_file.html?file_to_download_id=16602[/QUOTE]

Fencepost wrote:

Gray Watson's comments imply that the hot water from your faucet is unsafe for human consumption. Hogwash.

You know one of the effects of chronic lead poisoning is permanent brain damage (retardation) Fencepost!

In areas where water supply + plumbing has lead issues and other contaminates, that's often the case.

Sometimes its just plain nasty.

Lets farm legionaires in the lukewarm cold water lines. :rolleyes:

What you might save in water conservation on the hot side you'll likely waste waiting for pallatable cold tasty water on the cold side.

Turbidity, scale, concentrated minerals, and lead = yucky or yummy?

Add some iron eating bacteria, bioslime, other to the mix on a private water supply :eek: = delicious?

Who wants to futher concentrate chlorinated byproducts from a public supply? :p = tasty?

Concentrated salts from the softener = seasoned water?

And oh-so-good for the water heater vessle?

Not a fan of the metlund or d'mand type bypass/cross over to the cold line pumps. They are a health hazard to a potable plumbing system and those that use them.

Been advised against in certain areas all over for decades, some by EPA mandate warnings are sent to households effected and published in newspapers every year. Part of warnings included in the HUD brochure every home purchaser must receive at a closing (on lead issues).

Quote:

Do not cook with, or drink water from the hot water tap. Hot water can dissolve more lead quicker than cold water. If you need hot water, draw water from the cold tap and heat it on the stove or in the microwave.

Run the tap until water is cold to the touch before using it for drinking or cooking. This is especially important after the water has been standing in the pipes overnight or over many hours.

Quote:

Use only cold tap water for cooking, drinking, tooth-brushing or making a baby's formula. Hot water is more likely to leach lead from pipes and solder.

Quote:

Unlike most drinking water contaminants, lead is unusual in that it seldom occurs naturally in water supplies like rivers and lakes. Lead enters drinking water primarily as a result of the corrosion, or wearing away, of materials containing lead in the water distribution system and household plumbing. These materials include lead-based solder used to join copper pipe, brass and chrome-plated brass faucets, and in some cases, lead
service lines (pipes made of lead that connect a house to the water main). In 1986, Congress banned the use of lead solder containing greater than 0.2 percent lead, and restricted the lead content of faucets, pipes and other plumbing materials to 8.0 percent.

However, when water stands in lead pipes or plumbing systems containing lead for several hours or more, the lead may dissolve into drinking water. This means the first water drawn from the tap in the morning, or later in the afternoon after returning from work or school or after extended time away from home (weekends and holidays), can contain fairly high lead levels.

Remember, hot water can dissolve more lead quicker than cold water. That lukewarm water that a metlund or d'mand bypasses to your cold water line was once HOT water, and has been stagnant, and you're polluting your cold water lines with it, to remain stagnant and further dissolve even more lead in your cold water lines.

Thus, not a fan.

As far as Hogwash, no not fit to wash hogs, people, water plants, or supply anything in the food chain - because lead keeps getting passed on and concentrated in every link that follows in the chain, like many other pollutants.

Now if only you can remember lead isn't the only issue when it comes to water quality and health.

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