by April Scheinoha
It may be four years away, but the city of Thief River Falls has begun planning how it will phase out the refrigerant R-22, which is commonly referred to as Freon.
At its meeting Tuesday, Aug. 23, the Thief River Falls Committee of the Whole discussed how the Montreal Protocol will affect the city’s compressors at Ralph Engelstad Arena and the Huck Olson Memorial Civic Center. It is believed that it may cost as much as $200,000 to retrofit both arenas. Cost-share grants are available from the state of Minnesota.
The committee decided to await the results of a feasibility study to determine the best option for the city. Parks and Recreation Director Joe Amundson expected the study would be finished in September. An oil change will continue as planned on the REA compressors.
In 1987, the United States signed the Montreal Protocol. The treaty completely phases out hydrochlorofluorocarbons, ozone-depleting substances, by 2030. The schedule stipulates that 99.5 percent of hydrochlorofluorocarbons, including Freon, will be phased out in 2020.
More than 1,900 pounds of Freon are needed to refill the city’s compressors at REA and HOMCC. The majority – 1,200 pounds – are needed at REA. Amundson said the city needed to refill Freon at REA last year at a cost of $15 per pound.
Blended refrigerants, such as R-507 and R-410A, are an option for the city. However, Amundson noted they’re not proven and will possibly be eliminated in the future. “It really comes down to natural refrigerants, which leads to ammonia and CO2,” Amundson said.
The REA compressors are set up for ammonia. However, at some point in the construction process, they were converted to R-22 and never used ammonia.
Ammonia is more dangerous than R-22, but people would immediately smell an odor if there were a leak. Amundson noted that the REA compressor room would need its own ventilation system as well as a second egress. He indicated that the ramp door is the only egress out of the basement in this case.
Both arenas use indirect systems, meaning the gas is contained to the rooms. Amundson said he is under the impression that CO2 can’t be used in an indirect system. He expected that it would cost $100,000 in just concrete to retrofit the system if it were converted to a CO2 system. Many European arenas have such systems whereas two are located in the United States.