Design change beneficial in reducing domestic hot water tank corrosion

  1. (PDF, 865 KB)
  2. Get@NRC: Design change beneficial in reducing domestic hot water tank corrosion (Opens in a new window)
AuthorSearch for:
Journal titleCorrosion
Pages3032; # of pages: 3
Subjectstorage water heaters; corrosion; galvanized steel; temperature; Buildings
AbstractCorrosion of galvanized tanks was studied in domestic installations in rental housing projects of Central Mortgage and Housing Corporation at Peterborough, Belleville and Brantford, Ontario where sample tanks of the Ontario Hydro- Electric Power Commission were used and at Windsor, Ontario where regular commercial tanks were used. In the first series it was shown that temperature was an important factor affecting the corrosion. In the series conducted at Windsor it was shown that when 3-kw side-arm heaters were used instead of small immersion heaters the design change was the greatest single factor in reducing corrosion. Copper piping was shown to have an influence upon the corrosion, especially if a copper dip tube was used inside the tank. Results from tests involving corrosion inhibitors were inconclusive, perhaps because the concentration of about 10 ppm was too low. Micrographs of the galvanized coatings show that the corrosion attack was very irregular, starting with fissures and separating the zinc-iron layers from the base. These fissures appear even in the uncorroded edges indicating they are produced in the galvinizing process and that changes in this progress may improve the corrosion resistance. Reversal of potential between the steel and the zinc also is apparent in some micrographs.
Publication date
AffiliationNRC Institute for Research in Construction; National Research Council Canada
Peer reviewedNo
NRC number6238
NPARC number20377638
Export citationExport as RIS
Report a correctionReport a correction
Record identifier9f08b512-d6c0-46f0-a804-281aa472f70a
Record created2012-07-24
Record modified2016-05-09
Bookmark and share
  • Share this page with Facebook (Opens in a new window)
  • Share this page with Twitter (Opens in a new window)
  • Share this page with Google+ (Opens in a new window)
  • Share this page with Delicious (Opens in a new window)