HY-9 Concentrate is an all-purpose cleaner that is biodegradable and nontoxic. It can be used full strength or diluted, as needed. According to the manufacturer, the cleaner's buffered pH formula is gentle on the skin and safe for all HVAC equipment and washable surfaces. The company says that HY-9 is excellent for cleaning coated coils with expensive anticorrosion coatings. It does not contain butyl ether.
Hydro-Balance Corp., P.O. Box 730, Prosper, TX 75078; 800-527-5166; 972-394-7655 (fax); email@example.com; www.hydrobalance.com.