The Laing Autocirc1 is a cold water return type hot
water circulating system.

The Laing autocirc1 and Chilipepper CP6000 are cold-water-return hot water distribution systems.

By connecting a temperature controlled pump between the hot and cold water lines at a sink fixture, the autocirc1 circulates the hot water, similar to a traditional hot water circulating system. It just operates at a lower temperature so the cold water line being used as the return line isn't full of hot water all the time.

How the Autocirc 1 works

The autocirc pump inlet connects to the hot water line feeding your faucet, and the pump outlet connects to the cold water line also feeding the cold water faucet.  The pump circulates the hot water from the water heater, through the hot water piping, through the pump, and back to the heater through the cold water line.

When the water temperature at the pump reaches 95 degrees, the pump shuts off.  At that point the hot water is very close, probably only a few seconds away when you turn on the hot water tap. 

The hot water in the piping immediately begins to cool down, and when it reaches 85 degrees, the pump comes back on and pumps until again the water temperature reaches 95 degrees.

Now the cold water lines have 85 degree water in them, and again the hot water is very close to the fixture.  How close depends on how long it has been since the autocirc1 last shut off.  The cold water lines will now have luke-warm water in them, the actual temperature depending on how long since the pump last shut off.

Saving water and wasting energy

Keeping the pipes full of water that is above ambient temperature means your water heater will turn on more often and you will use more energy than without the system. The heat loss from the hot and cold water lines is constantly replenished by the water heater and thus you will spend more money on energy.

Although the pump turns on and off continuously, the motor only consumes 33 watts, and so the extra energy required to run the pump is minimal.

Not for tankless water heaters

The motor has only 1/150 horsepower, not enough for the autocirc1 to work with tankless water heaters. The unit is 8" tall, 4-1/2" in diameter, and weight 3 pounds.

The manufacture recommends using a water conditioner if you have hard water because it can cause scale build-up and eventually reduce the life of the pump and other system components.  The autocirc1 is easy to disassemble and clean if any debris get in the pump. Periodic cleaning is recommended in areas with hard water or if the water heater temperature is set higher than 140 degrees.

Home Depot's price is currently advertised as $239.00 and the unit has a 2 year warranty from date of manufacture or 1 year from the date of purchase (whichever is later).

The Chilipepper CP6000 is a demand hot water system.

With a hot water demand system, the pump is only activated when you want hot water. When you do, you press a button and the pump starts up, shutting off when the hot water arrives.

How the CP6000 works

The CP6000 uses a 1/3 horsepower motor, the most powerful on the market.  It produces a maximum pressure of about 60 psi and has a maximum flow of about 4 gallons per minute. Due to the high flow rate, the Chilipepper pump will work with any tankless water heater. Dimensions are 7-1/2" wide, 4-1/8" deep, and 3-1/2" tall. It weighs 4 pounds.

Like the Autocirc1, Chilipepper was designed to be connected to the plumbing with standard hoses used for connecting the faucets to the shut-off valves. All you need to do is turn off the shut-off valves under the sink, and connect up the hoses.

To achieve the small size and big power the CP6000 uses a brush type motor. The brushes will wear out after about 500 hours of operation.  If you use your pump 5 times a day 365 days per year, and it runs 1 minute each time (typical), then you will accumulate about 30 hours per year.  So you can expect your pump to last about 16 years.  At that point you would either need to put in new brushes and probably a new seal and go another 16 years.

The CP6000 has an adjustable temperature sensor so you can set the unit to turn off when it senses a temperature increase of 3 to 12 degrees, allowing you to fine tune the arrival of the hot water to your liking.

The CP6000 has a maximum run time of 3 minutes. If it doesn't detect an increase in temperature within 3 minutes it will shut off.  The reason for this is that if the water heater breaks down, there would never be an increase in temperature to shut it off and it would run forever.

To determine the maximum distance from the water heater that can be handled by the Chilipepper, we need to see how far the water would be pumped in 3 minutes. This will depend upon your plumbing.  The pump produces a typical flow of about 3 gallons per minute no matter what size the piping is.  The bigger the pipe the slower the water flow.

At 3 gpm the water velocity in 3/4" inch diameter type L copper pipe would be about 2 feet per second.  In type L 1/2" pipe the velocity would be about 4 feet per second.  Therefore, if the house is plumbed with 3/4" pipe, the maximum distance between your water heater and your fixture would be about 360 feet.  If plumbed with 1/2" dia. pipe, the distance would be about 720 feet.

Demand type systems to do not experience problems with scale buildup or hard water problems.  No periodic maintenance is necessary.

The CP6000 has an unconditional 30 day money back guarantee. It can be returned for a full refund for with no questions asked. It has a 5-year pro-rated warranty.

The CP6000 retails for $179.99 on the Chilipepper Website.

Chilipepper Sales 1380 Greg St., # 221 Sparks Nevada,  89431  PH (775)-359-1223