Commercial Refrigeration: Parallel Rack System or Condensing Units?
Refrigeration systems can be a costly, but vital, component in the food market and with them comes a lot of questions. With customers looking for the best way to allocate funds year over year, the refrigeration system(s) can be a bigger point of emphasis than what some realize. Debate between servicing the existing equipment or installing new equipment is one for existing systems while new systems often debate whether to go with a rack refrigeration system or individual condensing units. The truth is, there is not one set correct route to take as far as which system type to use; that all depends on what each user’s priorities are and what they are hoping to accomplish.
Parallel rack refrigeration systems work well for large cooling load requirements often broken up into several different individual cooling loads. Like we tend to see in grocery stores where there are multiple different refrigerated reach-in cases, island cases, and/or walk-in refrigerated spaces. While the upfront cost of installation is higher than individual condensing units for each eventual circuit, this option is often seen as much more energy efficient in the long run as there will almost always be some cooling load. This allows at least one compressor to stay powered on more often and significantly reduces the initial starting amp draw and short cycling from turning a compressor on and off. This system also allows for some redundancy with the ability to add a “back up” compressor or perhaps add controls to rotate the duty schedule for when certain compressors will be the primary versus the redundant option. This allows for more options to handle variable loads or if and when one of the compressors fails. While this type of system makes sense for much larger cooling load applications, it may be more ideal to go a different direction for smaller system applications.
Individual condensing units are often times the preferred option for smaller or more individualized setups. While there isn’t quite the same level of redundancy and customization in controls as what is available with a rack system, the upfront costs of going this route can be significantly less. In the event that one of the condensing units fails, that walk-in cooler/freezer, refrigerated case, etc. will also be non-operational but the rest of the systems will remain operating as the issue will be isolated to that individual system, barring a natural disaster, site wide power outage, etc.
While I only touched on a few key features for each option, your site’s situation is unique to you and should be treated as such. At Carlson & Stewart Refrigeration, Inc. we strive to design and install superior commercial and industrial refrigeration systems as well as help our clients make informed decisions to solve their needs now and into the future. For any questions on which refrigerant and system style may suite your operation’s needs, please contact Carlson & Stewart Refrigeration,