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Will hot water circulator wear out our copper pipes?

I have a 4 year old home with re-circulating hot water pump which we really love. I was recently told that the water movement would wear out our copper pipe. Should I be concerned and what can I do to prevent these problems?

Jim Noland
home builder - Marshall, Texas, USA
October 29, 2009

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Hi, Jim. Although it's true that everything wears out eventually, I do not think this is a realistic concern for many reasons including: First, I've never heard of it happening and there are millions of homes with such systems. When there are problems with copper pipe it's something galvanic or electrical, not wear.

Second, fluid dynamics dictates that there is actually very little water movement at the pipe wall. The water moves fast in the center of the pipe, and slows down as you get further away from the center, to almost no movement at all right at the boundary between the water and the pipe.

Third, you either get a build-up of scale or you get erosion, you don't get both; and a build up of scale is common.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
October 30, 2009

Turbulence in the system may cause a bit of a problem, but the water is not normally in a high flow mode when recirculating, so I like Ted's answer. It is a great system if you can afford the extra cost of heating.

James Watts
- Navarre, Florida
October 30, 2009