Metlund D'mand S-50T Hot Water D'mand Pump vs.
Chilipepper CP6000 Hot Water Pump
Comparing the
Metlund and Chilipepper Demand System Pumps - Two Water Conservation Products
A Look At The Metlund D'mand S-50T demand hot water Pump
This article compares the Metlund D'Mand system pump, the S-50T
model, to the Chilipepper CP6000. The information is predominately from
the Metlund web site, but since the author, William Lund, is the original
inventor of the MetLund pump, and the inventor of the Chilipepper pump,
he is well qualified to evaluate the two systems.
Lets start with what a demand hot water system is and how it works. A
demand hot water pumping system pumps the hot water from your water heater to
your fixture, sending the cooled off hot water already in the hot water piping
back to the inlet of the water heater. When hot water reaches the pump a
temperature sensor detects the increase in temperature and shuts off the pump.
You now have hot water at the fixture and you did not run any water down the
drain. If the pump is powerful enough you can get your hot water faster than
normal as well.
Metlund S-50T D'mand Pump
Metlund has three models, the S 50T, the S 70T, and the S 02T.
The S-50T is the smallest of the three models, and uses a TACO, Inc. model 006
hot water circulating pump.
Metlund lists the "performance" as "Gallons/Minute = 8" and
"Total Head = 10 ft."
This is a bit miss-leading.
Here are the pump curves from Taco's website.

As you can see from the curve labeled 006 the pump pumps "almost"
10 gallons per minute with no backpressure at all. "0 feet of head".
With a head of about 8 feet the flow stops completely.
Pushing 3-1/2 gallons per minute through 100 feet of 1/2"
Type L copper tubing, (which
would require the fixture to be less than 50 feet from the water heater), would
require over 10 feet of head.
Since the 006 cannot develop that much pressure, it probably
can't even push 3 gpm through the pipe.
From Takagi's website, the pressure drop through a model T-K3
tankless water heater at only 2.5 gallons per minute creates a head loss
of 5 feet.
If you have a tankless water heater that supplies a fixture 50
feet away, it's unlikely that the Metlund model S-05T would even achieve a flow
rate of 2 gallons per minute.
The Metlund S-50T-PF Kit ($356.00) Comes with two ½" threaded
male adapters two brass “T” compression fittings, two stainless steel
flex-lines, and one hard-wired button.
The pump must be plumbed to the water main side of the shut-off
valves under the sink due to the low head capabilities of the pump, and the high
head loss through the shut-off valves.
The pump shuts off when it senses an increase in temperature of
3°.
The Metlund S-50T-PF-R Kit ($411.55) is the same as S-50T-PF plus
one remote control package.
The S 50 T has a 3 year warranty. It's 1/40 of a horsepower motor
is whisper quiet. You won't even know when to turn on the hot water faucet.
The Chilipepper Model CP6000 Demand Hot Water Pump
The Chilipepper CP6000 is also a hot water demand system, and
does exactly the same thing as the S-50T. The Chilipepper was designed to
be hooked up with hoses, and thus needs a much more powerful motor to overcome
the head loss produced by the very small holes through typical faucet
connections.
A side benefit of the powerful motor is that the Chilipepper
produces a flow of about 3 gallons per minute with just about any plumbing
system. The Chilipepper pump has a cut-off head of 115 feet. With a
3 gallon per minute flow the Chilipepper has more than enough power to overcome
the head losses in any tankless water heater and hundreds of feet of pipe.
The CP6000 has an adjustable temperature increase for shut-off.
It's adjustable from an increase of from 3° to 12° via a knob on the front of
the case.
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. Just turn off the supply valves to the fixtures and
connect up the pump.
The high rpm 1/3 horsepower motor does make noise, and you can
hear it. That's a plus since you can hear the pump shut off and you know
it's time to turn on the faucet.
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.
Chilipepper Sales 1380 Greg St., # 221 Sparks Nevada, 89431
PH (775)-359-1223