Heat Exchanger Information

Our heat exchangers have been carefully developed over the past 30 years.

When we started building tanks, the common wisdom was to use ¾" Type L copper tubing as a heat exchanger for domestic hot water or other heat input or output needs.

The reality was that in most cases, ¾" copper tubing does not work as well as other sizes and configurations.  We discovered this through lengthy research and development with technical support from the University of Maine's Mechanical Engineering Department.  Using the results of our research, we were able to develop more compact heat exchangers that cost less money and actually perform better than filling the tank with less efficient masses of ¾" copper tubing or finned stainless steel or copper.

We recently performed more testing on our Domestic Hot Water heat exchanger that includes an antiscald valve.

We had tested it thoroughly ourselves and also had a local electric utility test it's performance in the late 1980's.  It seemed appropriate to update our data.

We heated a 180 gallon Heat Bank heat storage tank to 180˚ F.  Then, we set the antiscald valve to deliver a steady 110˚ F stream of hot water at 3.25 gallons per minute.  The system delivered 224 gallons of hot water at 110˚ F.  When the test was over, the tank temperature was within a few degrees of 110˚ F, which was our cutoff temperature for the test - the limit of usable domestic hot water.  Our findings show that all of the usable heat was delivered to the faucet with the highest efficiency.

We have tested our space heat exchangers and have found similar results.

We have always and will continue to develop the most cost effective way to store heat in unpressurized storage tanks and offer them to you at competitive prices.