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Hot Water Demand Systems
The S-02T Series DMAND System is a "Demand" type hot water delivery system, meaning that the hot water does not get pumped to your fixtures unless you "demand" it by pushing a button or activating the system in some other way.
The pump is located at a fixture such as under the bathroom sink or under the kitchen sink. Typically you would want to locate it at the end of a main hot water run that supplies other fixtures as well so you can use one pump for several fixtures. It depends of course, on how your home was plumbed.
When the pump senses a sudden increase in temperature it knows the hot water is arriving and it shuts off so the hot water does not get into the cold water line. The Metlund pumps turn off when they sense a 3 increase in temperature. Now you have hot water instantly at the fixture and anywhere else plumbed off the main line.
According to Metlund, the S-02T models are designed for use in large homes or commercial buildings where the distance from the water heater to the farthest fixture is greater than 100 feet. They are compatible with tankless water heaters.
The pump has a maximum pressure of about 13 PSI and a 1/8 horsepower motor.
The S-02T model weighs 16 lbs. Dimensions are 16" wide, 9" deep, and 6" tall. The motor used for the S-02T is a Taco Model 0011 Circulator pump.
Installation of the S-02T requires full 1/2" plumbing connections, normally requiring the removal of the angle stops under the sink to "T" into the piping. This is because the pump does not develop enough pressure to overcome the pressure drop that would occur in the small openings in fixture supply hoses.
The prices listed are from Metlund's website.
Metlund Dmand S-02T-PF Kit retails for about $797.50, and comes with flanges, two copper T compression fittings, and two stainless steel flex-lines for easy installation.
Metlund Dmand S-02T-PF-R Kit ($852.55) Same as S-02T-PF plus one remote control package.
The Chilipepper Model CP6000 Demand Hot Water Pump
The CP6000 is also a demand system very similar to the Metlund D'mand System. The major differences include a much more powerful motor...1/3 horsepower, a much higher maximum pump pressure...50 PSI, and an adjustable shut off sensing temperature. The range is 3 to 12, which allows you to fine tune the "hotness" of the delivered water when the pump shuts off.
The high rpm powerful motor makes enough noise that you can hear it run. Since you can hear it run you can hear it shut off and you then know it's time to turn on the hot water.
Connection to the plumbing is done with the same type of supply hoses as most of today's homes. The water supply to the house does not need to be turned off. You just shut off the angle stops under the sink, connect up the hoses, and turn the valves back on.
The CP6000 weighs 5 pounds, Dimensions are 6" wide, 8-1/4" deep, and 3-7/8" tall..
The CP6000 works great with any tankless water heater on the market regardless of brand or model.
The CP6000 retails for $179.99 and comes with a button, a six foot control wire, and two "T" fittings with adaptors for 1/2" or 3/8" hoses.
The CP6000 can be purchased bundled with a remote control receiver and transmitter for $215.99 on their website.
