The noise from the chilipepper appliance is only mentioned on their website as “you’ll know when the hot water has arrived because you’ll hear it stop”, or words to that affect. They continue to fail to mention just how loud it is, but the link below pretty much sums it up. I’ve also heard it described as “so loud the neighbors could hear it” and “so loud it scared the hair off our cat”. http://supersoundproofing.com/forum/index.php?PHPSESSID=31dg6e6cij1ekd0aef8&topic=1332.0

Interesting fact, the Chilipepper appliance and the ACT Metlund d’mand system were both invented by the same two people, Dennis Metzger and William Lund. As, Mr. Lund wrote in his chilipepper article;

“Our company was a tiny little two man operation. Needless to say marketing a new product with no money is difficult. We ended up licensing it to ACT, assigning the patents to ACT, and giving them the name Metlund. The product is now known as ACT Metlund D’MAND system. Dennis and I are no longer affiliated with the company. It was one of those cases where the two naïve inventors meet the new company’s lawyers and the next thing we know we are out on our behinds with nothing to show for it.but that’s another story.”

The full story is on chilipeppers website http://www.chilipepperapp.com/Artcls31-D-mand.htm

While both ACT Metlund D’mand system and RedyTemp Hot Water Optimizer use TACO pumps there are some distinct differences between the two systems. The Metlund system has only one mode of operation and requires activation by push-button or sensor. The RedyTemp has 4 user selectable modes, Single-cycle on demand, timer/scheduled, combination of timer w/on-demand overide or always on (cycling on-off based on temperature).

The Metlund system stops pumping when it senses a 3F to 5F degree rise in temperature (ambient temperature) typically a 30 second wait after activation and then a bit more after running some amount of water down the drain waiting on above ambient temperatured hot water to arrive. The RedyTemp stops pumping when the water temperature at the sink / sensor is at “your” chosen / dialed-in temperature. RedyTemp owners who desire cooler cold water simply turn the temperature dial down just a hair (adustable to 0.5F interval). The Metlund systems require installing “T” fittings just before shutoff valves (requires draining line) while RedyTemp utilizes existing hoses from faucet to RedyTemp.

RedyTemps RJ11 jack makes multiple push-button installations easier using affordable phone cords (.99 cent store 100′) wires and phoneline expansion adapters. RedyTemp TL-series systems work with tankless and tank water heaters and have relocatable “water contacting” temperature probes. This allows for the system to be installed most anywhere on a closed loop system (with dedicated hot water loop) and by locating the temperature probe near the last hot water load on the loop significant energy savings can be realized by not needlessly heating the pipes between the last load on the loop and the hot water source. Thus, extending the life of both the water heater and the pump.

The biggest difference between the RedyTemp and other systems on the market is RedyTemp’s dual directional flow control by utilizing a built-in checkvalve and a “normally closed” solenoid valve that opens only during an active pumping cycle. Todays, typical systems use a single check valve which prevents cold water to hot waterline crossover. But, often does little to prevent water from the hot water line from entering the cold water line during cold water usage events. When cold water is used in / out of the home the water pressure in the cold water line drops leaving the hot water line water pressure higher.

This higher pressure in the hot water line can easily overpower spring based checkvalves and “normally open” thermostatic / comfort valves, making it difficult for users to obtain water exclusively from their cold water line, let alone cold water. The biggest mistake people make when choosing a hot water circulator is making their choice based on ease of installation and / or cheapest price. Only after they’ve installed the system do they realize that the choice they made will now affect the efficiency of their lifestyle everyday.

Do hot water circulators waste energy, yes they can…a lot. Can even the most efficient, optimized, timer-based hot water circulation system save energy? I believe it is possible but, not through push-button on-demand because asking people to push a button and then still wait for 30 seconds is asking a lot of most people. Most families live a lifestyle that is routine, Monday through Friday, everyone wakes up, gets ready for school or work, everyone comes home, dinner, getting ready for bed, etc.

Accurate circulation scheduling together with back-to-back shower schedules can minimize system operations. A lot of bathrooms have multiple lights / vanity. Entering the bathroom, pushing a button, waiting 30 seconds multiple times a day vs. entering a bathroom, turning on hot water that’s instant (scheduled), depending on the watts of the lighting and number of bulbs. I think it is possible to save energy, but only if the hot water circulator has the right technology, control capabilities and a family that is willing to live a greener lifestyle.

also, maybe you can justify the energy waste since you’re (still) on mains, but the pump is a vampire in an exclusively solar home. one is conscious in turning it on and off, balancing this against the water waste.
i feel that by 2010 all building should be done for easy translation to solar and wind.

only the Amsih will still have main electricity in 20 years (hahahaha…i think that’s funny)

a bucket in the shower, a basin in all the sinks…..flush the piss down, water something, ….
this too is ‘just another step’, but one the re-inforces one’s connection to one’s use of resources.

the important words here are :conscious and connection.