Secondary Refrigerant

Analysis
Samples of Secondary Refrigerant are analyzed at the end of the season.
These tests provide us with accurate readings of coolant purity and strength. We measure the level of pH, ammonia, rust inhibitor and look for contaminants such as iron and suspended solids. This is just one of the diagnostic services Norlock performs annually for it's clients thus preventing serious chiller failure.

Filtration
Suspended solids can be made up of a number of things, from chemicals that have fallen out of solution, to foreign contaminants in your system. These solids eventually begin to accumulate on the walls of the return bends as well as the straight lengths of pipe and impair heat transfer. If this goes undetected, it could eventually block the Secondary Refrigerant Loop as well as compromise heat transfer efficiency.
Annual maintenance for rinks that are equipped with Secondary Refrigerant Filtration Systems include installing a new filter cartridge at annual startup. Filter cartridges should be regularly cleaned or exchanged throughout the season as part of the regular maintenance schedule.

Specific Gravity & Brine
The specific gravity of your Brine coolant should be checked regularly by the rink staff on a regular basis by using a hydrometer. For an accurate reading, it is important to let the brine sample warm up before testing. The hydrometer is to be used in a brine medium at 60ºF.
Specific gravity is measured relative to water which has a specific gravity of 1, and is adjusted by adding calcium chloride flake or diluting the brine with water.

As the concentration increases, more energy is required to pump the Secondary Refrigerant through the system, but the freezing point of brine decreases. (Note: at a specific gravity of 1.2, the freezing point reverses and begins to increase). The recommended specific gravity for brine is 1.21 which has a concentration of 22.4% actual calcium chloride at freezing point of -94ºF (-23ºC). Most brine pumps are selected based on a specific gravity of 1.21, so for proper system performance, it is important to maintain this level.