When it comes to medical refrigeration, it is critical that both coolers and freezers maintain a steady temperature to avoid compromising the samples stored inside. Siemens Medical Devices is a prominent manufacturer of state-of-the-art medical equipment in Walpole, MA, whose existing system needed an upgrade.
The current refrigeration system that Siemens had installed was a 60 x 60ft cooler and freezer combination. The freezer was located inside the cooler so that the cold air in the cooler could act as a buffer between the hot air outside and the inner freezer.
Medical refrigeration systems are required to have redundancy built into the system. Most samples and products stored for medical purposes are susceptible to slight temperature variations, so maintaining a steady temperature is vital. Siemens’ current cooler and freezer combination operated on a staged refrigeration system, instead.
In a staged refrigeration system, there are multiple systems installed to maintain the temperature, and when the temperature warms, one of the systems kicks on. Another system will turn on if the first does not cool the space adequately, and so on. Although this system did help to protect the internal temperature from rising, it was not an official “redundant” system.
Additionally, Siemens was running out of freezer space and needed to upgrade to a larger freezer.
Problem: The current walk-in cooler and freezer combination for Siemens Medical Devices needed an upgrade. Siemens needed more freezer space for their samples and products, as well as a redundant system that would replace the staged system they were currently using.
Solution: N.E.T.R. Inc. built a three-pipe redundant refrigeration system with an entrance vestibule and a larger freezer space. This new freezer system has a hot gas line that will help to maintain the temperature inside the freezer within a tenth of a degree – which is required for storing medical samples.
The Installation
N.E.T.R. Inc. worked with Siemens to develop a system that would meet all their requirements. First, they needed additional freezer space and less cooler space, so a new cooler and freezer combination was designed to replace the old one. Second, the system had to be redundant to keep the samples and products at a stable temperature. Third, medical freezers are required to maintain temperatures within a tenth of a degree of variation, so the system had to be incredibly precise.
The new cooler and freezer unit was designed with a 12ft x 12ft vestibule. A forklift can enter the vestibule through a set of doors, which close to keep the warm air out. Then, the second set of doors open into the freezer. This vestibule acts as a buffer between the hot exterior air and the freezer air, so the contents are never at risk for temperature fluctuation.
The refrigeration condenser units were installed on the roof of the building on top of a steel rack. The units had to be lifted into place with a crane. The installation of these condensers went smoothly and helped the overall process remain on schedule.
The freezer had a redundant refrigeration system installed, as well. A redundant system has two refrigeration systems built into one box. The two units will alternate running from day to day. This process lengthens the life of both systems and evens out the daily wear and tear. In addition, if one system does not kick on when it is supposed to the second system will run in its place. The unit will also alert Siemens if one of the refrigeration systems is down so that it can be repaired quickly.
Lastly, N.E.T.R. Inc. installed a hot gas bypass system that will help it to maintain a constant temperature within a tenth of a degree, as required. This hot gas line runs straight to the evaporator and routinely false-loads the system with a little hot gas. The hot air tricks the refrigeration system into running continually, so the temperature never fluctuates.
Unlike a food refrigerator which will cool to 38 degrees and then warm to 40 degrees before the system begins to cool again, the medical system must always keep a consistent temperature. The hot gas line ensures that the freezer is continuously running, so the samples are always protected, and the temperature never fluctuates.
This electrical, three-pipe system was the best solution for precise temperature control. It features a liquid line, suction line, and the hot gas line that all run directly into the freezer’s refrigeration systems to maintain the proper temperatures.
Since the Install
Siemens Medical Devices has been extremely pleased with their new freezer system. It has been operational for several months and has run consistently without issues. The ample space has allowed them to store three times the samples and products they had previously, which has been an excellent benefit.
After the system was installed, Siemens performed the validation test. This test is done to ensure that every corner and pocket of the freezer is kept at the same temperature so that no samples will be compromised by inadequate cooling. The system passed, and they have been able to make great use of the additional freezer space.
In Need of an Upgrade?
Is your business in need of a cooler or freezer upgrade? Do you find yourself running out of space, or dealing with fluctuating temperatures that ruin your supplies? If so, it’s time to call N.E.T.R. Inc. in Boston, MA.
We specialize in a wide variety of heating and cooling problems, and our experts will work side by side with you to design a system that meets your needs. Over the years we’ve helped countless businesses upgrade their walk-in cooler and freezers, upgrade to more efficient systems, or design state-of-the-art solutions for medical storage – like this install in Walpole, MA, for Siemens Medical Devices.
N.E.T.R. Inc. also specializes in heating and air conditioning solutions for commercial properties. Contact us today to learn more!