Leak Requires Hockey Rink Save
Sealant Keeps Skaters on Ice
An HCFC-22 refrigerant leak in its flooded tube-style chiller system threatened the Arcadia Ice Arena with a potential door-closing financial crisis, had it not been for the ingenuity of its maintenance engineer and today's commercial refrigeration leak sealants.
The 47-year-old rink in Phoenix was facing a potential mountain of costs due to a sudden, small, detectable leak in its flooded tube chiller. Losing some or all of the system's 1,100 pounds of R-22 at today's prices would have cost the rink tens of thousands of dollars to recharge it.
Patrick Manion, Arcadia's Environmental Protection Agency (EPA)-certified maintenance engineer and a lifelong hockey player, perhaps had the biggest save of his career when he resolved the leak with two changes of filter drier cores, five cans of Dry-R moisture eliminator, and 15 cans of Super Seal Advanced leak sealant, the latter two manufactured by Cliplight Mfg., Toronto.
Few of the alternative choices were affordable for Arcadia, which is a family-owned operation in an industry with slim profit margins, according to Jim Rogers, president, Arcadia Ice Arena, who bought the operation in 2001 and has been continually improving it even though budgets are limited.
Besides sealing, Manion had several potentially more costly alternatives.
• Repairing the leak conventionally would have required an outside HVAC service contractor, costing upwards of $30,000. Furthermore, closing the National Hockey League-sized rink for a week or more during the repair might have cost thousands of dollars in revenue and potentially lost clientele.
• Replacing the chiller system and components would have cost hundreds of thousands of dollars. Weeks of portable chiller rentals would also have been necessary to maintain the ice since the 200-by-85-foot rink's 1960s-style sand floor design can't be partially melted and refrozen.
• Replacing 1,100 pounds of R-22 in the event of a catastrophic leak would also create a financial burden of an estimated $20,000 in refrigerant costs, excluding labor and the leak's damage to the environment.
• A conversion to HFC-410A to reduce the dependence on R-22 was also cost-prohibitive, said those involved in the project. The compressors were manufactured in 1964. The oil coalescer/oil recovery system, chiller, evaporative condenser, and all refrigerant piping would have needed replacing to operate under R-410A's higher pressures. The lower-pressure HFC-407 series of refrigerant blends is also not an acceptable solution for flooded tube chillers, those researching alternatives said.
Besides slowly leaking the R-22 charge, the leak also possibly introduced moisture to the R-22 circuit, which cools a concentrated sodium chloride brine. The brine circulates 9 miles of 1-inch-diameter tubing frozen into the sand layer beneath the ice surface. Tiny bubbles appearing in the brine system filter elements' transparent housing also raised the possibility of cross- contamination.
Manion wasn't familiar with today's organosilane-based sealants, but Phoenix-based distributors, American Refrigeration Supplies (ARS) and Refrigeration Supplies Distributor (RSD), both recommended Super Seal for systems 5 tons and larger.
Since sealants typically work best on microleaks 300 microns and smaller, Manion was a bit skeptical. Based on Cliplight customer service department's instructions, plus guarantees from the sealant and drying agent's inventor — Paul Appler, director of research, Cliplight — Manion was assured that the brine's positive calcium ion (Ca2+) and negatively charged chloride (CI-) ions wouldn't interfere with the bonding process. Manion applied the sealant after an extended period of drying out the system. Super Seal is designed to remain a liquid that flows with the refrigerant and oil throughout a system. In the event of a leak, the dew point-induced condensation around the exit hole creates enough moisture to create a chemical reaction that hardens the organosilanes into a permanent bond around the hole.
To dry out the system beforehand, Manion used a few dozen drier filter cores, which were weighed before and after on a digital scale to establish the drying trend decreased moisture. After removing the majority of moisture, Manion applied Dry-R, which eliminates up to 60 drops of moisture per can. A moisture-indicating sight glass that he installed also confirmed the system was dry and ready to be sealed.
Since then, the refrigeration system has been operating without refrigerant leaks, according to Manion. However he admitted he might never know about future leaks because with the sealant perpetually circulating in the system a leak could occur and quickly be sealed unbeknownst by anyone.
In that event, it will be another save by Manion for Phoenix's oldest hockey rink.