Veteran HVAC/R service technician, Gregg Ponke had a busy day recently. He helped his HVAC/R service company’s hospital client avert a $2,500 service call bill, saved $15,000 worth of food from defrosting and prevented refrigerants from leaking into the environment.

The leaking system, a 400 square foot walk-in freezer in the commissary of the 186-bed Port Huron Hospital (Michigan, USA)--was checked intensively with electronic leak detection equipment by Ponke over the course of a few days.  Unfortunately, the phantom leak was finally suspected to be at the piping manifold near the outlet of the five-ton system’s thermostatically controlled expansion valve (TXV). Not only was the leak inaccessible, but there was also an imminent danger of damaging nearby manifold solder joints during the brazing process, according to Ponke, one of eight service technicians employed by Watson Brothers Heating & Cooling (Port Huron).

Consequently, Ponke was planning at least one or two full day’s work to pump down the system of its refrigerant, replace the manifold, and replace the R-406a refrigerant all for an estimated $2,000. A worse problem was the lack of alternative freezer space for storing the hundreds of pounds of frozen food and the possible interruption of the cafeteria’s food service.  “We were looking at either losing all the food or renting a semi-truck trailer freezer at a rate of $1,000 per day, not to mention all the hospital labor of moving the food into it,” said Brian Hase, hvac/r systems mechanic, Port Huron Hospital.

It was this type of situation Ponke was waiting for to try Super Seal 3 Phase, a refrigeration sealant invented by a refrigeration technician and manufactured by Cliplight Mfg. (Toronto). Recommended by Keith Montville, branch manager of local HVAC distributor Downriver Refrigeration Supply, the sealant is a patented formula of organosilanes that remain in a liquid state with the refrigerant once injected into the refrigeration system. When the refrigerant leaks out of a hole of 300 microns or smaller however, the introduction of atmospheric moisture causes Super Seal to crystallize into a hardened bond around the exit point thus stopping the leak.

Typically, Ponke would prepare such a system for sealing by checking for leaks with his CPS Products Inc., Hialeah, Fla., electronic leak detector and then verifying the leak with soap bubbles. If a leak is found, he tries to repair it conventionally. In the hospital case at least one other undetectable leak was suspected. Next, filter/dryer are changed out to ensure no moisture or particulates are freely circulating in the system. Then the refrigerant is reclaimed with a Robinair—SPX Division, Miramar, Fla., reclaim machine and the entire system is evacuated to 250 to 300 microns.  Because the food might have been lost during a pump down and one leak was undetectable and suspected to be inaccessible, Ponke chose to just apply the sealant. 

Based on his 25 years experience and the fact that the system had developed past leaks in other areas, Ponke believes the unit probably would have developed future leaks if the sealant hadn’t been applied. “It looked like leaks were going to be a regular occurrence, but now after the application, everything has been quiet for over nine months,” Ponke said. “It’s possible another leak may have already appeared since the repair, but nobody will know because the sealant continues to flow throughout the system plugging leaks as they occur,” said Ponke, who has a long-term service history with the unit including retrofitting it from R-12 to R-406a several years ago.

Since the cooler repair, the hospital has successfully used Super Seal HVACR, which is designed for systems between 1.5 and 5 tons, on several leaking heat pumps, plus Super Seal ACR on two failing window units. Ponke stumbled upon Super Seal while searching for a solution to the seemingly impossible situation at the hospital, however other local service technicians are learning about it at Downriver Refrigeration Supply from the distributor’s countertop displays and detailed instructional brochure, plus a recent new product seminar, according to Montville.  “More and more service techs are trying it and we haven’t had one complaint about it during the three years we’ve carried it,” said Montville.

With full confidence in the product from the successful hospital application, Ponke’s second use of sealant was a 30-year-old Bally Refrigerated Boxes ( Morehead City, N.C.) walk-in cooler at the local American Legion. With no access to a leaking return line elbow, Ponke was faced with the prospect of removing and bench repairing the evaporator coil.  Because of the unit’s age, the piping systems were developing leaks that Ponke found himself fixing almost continuously. “I told the post commander that if I couldn’t’ repair the leak, they had to buy a new evaporator coil,” said Ponke.  “The commander said they had absolutely no money, so using a sealant really saved them over $1,000 and kept their food service operating.”

Because of Ponke’s success with sealants, other Watson Bros’ service techs are considering it based on Ponke’s recommendation. “Our service techs have the freedom to try different products to solve on-site problems,” said Watson Bros.’ service manager, Dwayne Beem.  As for Ponke, detected and accessible leaks are still repaired conventionally if possible. However, phantom leaks will get the sealant application. “If I had this tool 25 years ago when I started in this business, my life would have been a lot easier,” Ponke said. 

Source: Cliplight