Summary
8’ x 10’ standard walk-in freezer with 2 hp compressor R-404A
KE2 Evaporator Efficiency controller
- Eliminated service calls related to iced evaporator
- Reduced defrost cycles by 86%
- Eliminated need for manual defrosting
- Lessened load on the compressor eliminating need to add supplemental
12 months
Established in 1967, Circle of Concern is a nonprofit organization that provides food and long-term emergency assistance to low-income families in western St. Louis County. In 2009 Circle of Concern fed 18,036 people, serving over $900,000 worth of donated and purchased food. Among the items Circle provides are meat, dairy and produce. Approximately two tons of meat is received in every two weeks, with over 60,000 lbs of fresh meat processed through the freezer in a year.
KE2 Therm Solutions was called in by local contractor Ron Licklider of Ozark Engineering to help solve a reoccurring problem in the Circle of Concern’s 10’ x 8’ walk-in freezer. Despite the mechanical time clock being set to defrost three times per day, each time a large shipment was received the evaporator would freeze-up, requiring a service call to manually initiate defrost, or as Executive Director Glenn Koenen explained, We’d see the temperature kick up 8, 9, 10 then 20 degrees and we knew the problem.
Koenen continued, We were using a heat gun and a hair dryer to thaw the evaporator at least once a month. With temperatures like we had in August, probably breakout the hair dryer and heat gun.
Serving over 18,000 people in 2009, Circle of Concern relies heavily on their walk-in freezer. Constant issues with the evaporator freezing up were hampering their efforts to serve the community.
While not specifically designed for trouble applications, the Defrost-On-Demand programming found in the KE2 Evaporator Efficiency was well suited to the task. By regulating the number of defrosts based on the build up of frost on the coil, the KE2 Therm controller only initiates a defrost when required. The result is that the service calls to manually defrost the coil after receiving each load of fresh meat into the freezer have been eliminated. While in the defrost mode, the KE2 Evaporator Efficiency also ensures that the coil is free of frost before the cycle is terminated. This is not always the case with a mechanical time clock. With the KE2 Evaporator Efficiency technology, Circle of Concern has seen a reduction in defrosts of 86%, going from 93 defrosts down to 13, in the month of July.
The KE2 Evaporator Efficiency also provided another benefit to Circle of Concern. The walk-in was designed primarily for storing already frozen items. When the bi-monthly shipment of fresh meat arrived the load strained the capability of the unit’s 2 hp compressor. Licklider remarked, It’s a fine line from having enough capacity to freeze a product and just hold temperature. It takes more capacity to bring it down. At one time we were looking at adding a compressor, but now the capacity we save from fewer defrosts is capacity we are able to use for cooling.
Conclusion
Circle of Concern’s installation with KE2Therm components has been in operation since June 2010, and the iced evaporator has not been an issue since that time. Although the KE2 Therm equipment was donated to Circle of Concern, had Circle been a paid installation (including equipment and estimated labor), the savings they saw by eliminating 10+ service calls per year, and from reducing their electrical expense by decreasing defrosts 86%, put them on track for a payback of under 12 months.
