Keeping it Frozen
The ice maintenance team is responsible for the refrigeration system that keeps the ice sheet frozen. In-direct refrigeration systems are the most popular in the industry. This method transfers heat from the ice surface and into the colder brine located in the piping. The brine absorbs the heat and is pumped away towards the chiller unit. The chiller unit is located in the mechanical room along with the compressor and condenser. The chiller contains a super-cooled refrigerant that absorbs the heat from the brine.
The refrigerant has a low boiling point so the heat being transferred from the brine causes it to evaporate. The compressor pulls the vaporized refrigerant from the chiller and pressurizes it drastically raising the temperature. From here it moves to the condenser and is exposed too cooler ambient air or water. This makes the gas condense returning to a liquid state. It is then pumped back to the chiller where the cycle starts over again.
Refrigeration system components
Underground Structures:
The Ice sheet is located on top of a cold concrete slab housing the chiller piping, with an insulating layer just below it. This insulating layer can expand and contract with the desired surface ice temperature. A heated concrete slab is below the insulation layer. This is necessary to keep the ground from freezing which would expand and crack the entire structure. All of these layers sit on a gravel and sand foundation containing a groundwater drain.
Heat Transfer Station:
Chiller – shell and tube, or plate and frame
Screw Compressor
Condenser – There are three styles evaporative, air-cooled, and water-cooled. The type used depends on the climate the rink is located in.
Pumps – control the rate of circulation of the refrigerant
Refrigerants
Ammonia
R22
Calcium-Chloride
Ethylene Glycol
Propylene Glycol
Whaley Products
 Packaged Chillers Non-expandable (integrated pump tank) 1.5Ton – 20Ton Single / Dual Circuits Single / Dual Pumps |
 SAE Series Modular Chillers Expandable (pump & tank on separate skid) 1.5Ton – 200Ton Single / Dual Circuits |
 SAR Series Split Chillers Expandable (Outdoor Condensing Unit) (pump, tank, evaporator on indoor skid) 1.5Ton – 200Ton Single / Dual Circuits |