Visit the Energy Systems Laboratory Homepage.
Corrosion of Aluminum-fin, Copper-tube Heat Exchange Coils
Abstract
Over the past several years the HVAC industry
has experienced a large increase in instances of leaks
in the central portion of aluminum-finned, coppertube
heat exchange coils. These leaks are
characterized as being very small in size and very
high in numbers within a single coil. There are many
chemical species that can cause these coil leaks,
including chlorides from pool chemicals and clothes
washing, sulfur from tap water, lubricants and nearby
industries, and ammonia compounds from cleaners or
nearby industries. However this recent increase in
reported coil leaks is being attributed to a newly
discovered class of corroding agents. These are low
molecular weight organic acids such as acetic acid
and formic acid.
This paper gives some background information
on leak causes and then presents the diagnostic
procedures typically used to determine these causes.
Results of some of these analyses are also presented.
As many of these procedures are new and often
company-specific, there are no accepted industry
standard procedures to test process chemicals or
application contaminants for copper tube corrosion
potential. Industry supported research has begun to
develop a bench test for this.
Citation
Field, J. E. (2002). Corrosion of Aluminum-fin, Copper-tube Heat Exchange Coils. Energy Systems Laboratory (http://esl.tamu.edu); Texas A&M University (http://www.tamu.edu). Available electronically from https : / /hdl .handle .net /1969 .1 /4580.