Rink

In a past issue of RINK Magazine you answered a question about techniques to control energy cost and mentioned that ice surface temperature should be 22-24˚ F. We purchased a handheld infrared thermometer but seem to get different readings than we do from the other infrared thermometers. What's going on? First, it's great to hear that you purchased an infrared thermometer, which will allow you to be consistent with your surface temperature. Your customers will appreciate that. As for the checking of proper readings of an infrared thermometer, there are a couple of important steps to follow. 1) It is required to let an infrared thermometer get to the temperature of the room before you use it. If you take the thermometer from an office or compressor room, you must let it cool down to the rink area temperature before you will get an accurate reading 2) A trick we use to test the accuracy of an infrared thermometer is to take a cup of water and pour it on the ice. The wet section should read over 32˚ and the edges and frozen part should be at 32˚ or below. This is a good and fairly accurate method of testing a thermometer. We have found most infrared thermometers to be accurate within 2 degrees. 3) Try to only use one infrared thermometer for your readings. If you use different thermometers you will receive slightly different readings. Infrared thermometers can be purchased for as little as $50. However, like most things, if you can budget more for a thermometer you should because you get what you pay for. More expensive units will be more accurate for a longer period of time. Benchmark your readings and compare them to the weather conditions outside. This will help you to know how to make proper adjustments to your refrigeration system for efficient operation. How does my compressor system know when to turn the compressors on and off? Understanding where your rink is controlled from is very important for efficient operation of your refrigeration system. As I have mentioned in the past, it is the surface temperature of the ice that is the concern of the rink operator. However, most refrigeration systems are not controlled by the ice surface temperature but rather by the temperature of the concrete slab under the ice, or the temperature of the return brine/glycol from the rink floor. So when you think about it, if you are controlling the temperature with the return brine/glycol temperature, the heat from the ice resurfacing must travel through the ice and the concrete slab or sand, then to the brine/glycol in the pipes, and then travel back to the refrigeration room before the system knows this heat has been applied. Only then will the system react and turn on the compressors. For this reason, ice at some facilities will set up faster than others. There are a few rinks that actually control the compressors with infrared thermometers in the ceiling. These thermometers will adjust the compressors as soon as resurfacing is detected, and shut them off as soon as the surface temperature is correct. These systems also react to building conditions as they change during events such as public skating or when a large crowd is in the building. This system is the most efficient way to control the ice and any compressor system can be changed to operate this way. However, if you do not have an infrared system, it is up to the operator to adjust the refrigeration system each day to compensate for the programming on the rink and also the outside weather conditions. Unfortunately, many operators do not do this and leave the same compressor settings until the ice conditions get so bad that is noticeable to the customers. So, do you know how your compressor system is being controlled? ★ ask dave 58 R INK MAGAZ INE march/april 2008 ■ You have rink questions. Dave has rink answers. Send your questions to AskDave@rinkmagazine.com. Infrared ice temperature controller. Daily reading of the ice surface temperature will insure efficient refrigeration operation. STAR PHOTO STAR PHOTO

• Cover