Diagram of trunk and twig recirculation system with demand pumps, and a photo of Gary Klein

Gary Klein Turned Me Into a Sink

In attending several of Gary’s teaching/training sessions, I have watched dozens of people get that smile that happens when a light goes on in your head. We all take showers or baths, but before Gary asked, how many of us have pondered how much hot (or previously heated) water went down the drain while we waited?  …and why?  Gary asked himself those questions about 20 years ago, and then went on a quest to find out.  Because he did, people all over are now thinking about hot water waste in ways they never did before. -- Nehemiah Stone, the Benningfield Group

I was astonished, at the 2015 ACEEE Hot Water Forum, to hear Gary explain how much water and energy are wasted just by people turning on the tap and going off to do other things because the hot water took so long to arrive. I was never a sink, but he turned me into a water heater once to demonstrate the length of a plumbing run between the heater and a sink (played by somebody else)! -- Randy Schuyler, Water Heater Rescue


Gary Klein has been in hot water a long time and I'm glad of it. His ability and zeal for explaining the consequences of poor plumbing design are amazing. He makes people aware of the problems. His work has helped us all think of domestic hot water systems as systems. -- Jim Lutz 

Gary Klein has a particular way of looking at problems.  He likes to define problems with "order of magnitude" observations.  Is that leak one gallon per minute, ten or a hundred gpm?  We may not know exactly, but we do know close enough.  Armed with that information, we can come up with rational ways forward to deal with whatever problem.  By asking the right questions, Gary has the ability to cut through the barriers that slow us down and get to effective remedies.  Having a good brain, persistence, humanity and humor has allowed Gary to truly change the world. -- Larry Weingarten

Gary Klein got tired of waiting four minutes for hot water to arrive at the sink of the house he’d moved into, and it changed his career forever.  He’s done research and advocacy ever since, and has led the charge for how to plumb things better.  His work is profoundly affecting building codes for both residential and commercial construction, and has been very, very productive -– even in getting the research commissioned that is giving us the information we need to support his findings and leading to even better hot water architectures.  I can relate to that:   When we moved into an old house that was new to us in 1979, we discovered that it had used 2,200 gallons of oil/year, and the boiler dated from about 1912.  I got curious, abandoned my research area (geological oceanography and paleoclimate), and moved into building sciences.  I recognize and respect Gary’s path of discovery, and hope that I’ve been able to contribute a small fraction of what he has given all of us. -- Harvey Sachs, ACEEE