You’ve heard me say many times about condenser water: no treatment is the best treatment. I know there can be exceptions to the rule, however I bear witness to a condenser that was installed 26 years ago that is currently being retired, not particularly because it’s worn out, it just needs to be larger. The treatment of this condenser included natural passification using city-chlorinated water with daily pH checks that maintained its pH between 7.5 and 9.0 throughout its useful life. If the daily checks showed the pH getting out of bounds, the bleed-off was checked or increased, or the entire sump was drained, cleaned, and refilled. Some pipe had lost paint, but it shows no unusual corrosion. Had acid- or mineral-based water treatment been used, these pipes would be badly corroded.
I recall a condenser installed on a project in Honduras that inadvertently got treatment, unknown to me. It developed pin holes and the coil section had to be replaced. The treatment was stopped, but the interesting thing to note was that another project at the same plant provided a large galvanized condenser stand which provided for three new condensers and the relocation of the abused condenser. Even though no treatment was being used six months after the condensers and the abused condenser relocated, the spray-off from the abused condenser – residual minerals, etc. – created a well-defined six-foot circle around the abused condenser, which showed rusting of the galvanized condenser platform just adjacent to the abused condenser.
There have been a few articles put out over the last few years that say that a little deposit on the coils could provide a protective coating. Other than algae, natural zinc hot-dipped galvanization is a mold inhibitor for condensers. RR
To read the rest of the articles from the Spring 2015 Refrigeration Review, click the links below.
- The Noble Condenser
- IIAR 2 or ASHRAE 15
- Machinery Room Ventilation
- Comments to CSB Regarding the Safety Bulletin
- Questions for EPA
- Critical Flow
Engineering