The Hotline: 12/05/2005
By Herman Krantz
Sun City, Calif.
I want to make readers aware of a technology developed in the late 1960s and early 70s that I believe is still viable today.
In those years, Rigidbilt Inc. developed a "box" type distributor for use primarily with ammonia coils using recirculated liquid and horizontal airflow. I, as vice president and engineer at Rigidbilt, along with Bob Lamprectt, then president at Rigidbilt, and Eugene Rytlewski, a consultant who spent 34 years with Westerlin and Campbell (the Chicago contracting office of York Corp.), were looking for uniform liquid distribution at varying liquid pressures and volumes, along with uniform distribution of hot gas for defrosting.
What evolved was a series of 3/8-inch O.D. steel tubes extending up inside a 2-1/2- by 3-1/2-inch rectangular steel tube with orifices in the tubes inside the rectangular box. The project included refinement in sizing, locating of the orifices, and internal construction.
After Rigidbilt used the distributor for a few years, Bill Richards of H.A. Phillips Co. (who was so extremely helpful to Rigidbilt in our ammonia work) started referring to our distributor as "Herman's Box Distributor." Thereafter, a number of contractors and mutual acquaintances referred to the distributor by the same name, and I, a young sales engineer, relatively new to the industry, was quite proud to have developed such a practical and useful adjunct to our coils.
By the time Bob and I retired from Rigidbilt in 1984, the company was using this distributor not only on ammonia coils, but also on a great many refrigerant coils because it was so simple, reliable, and trouble-free. By this time, many of our customers were asking to have the distributor on their equipment.
Rigidbilt used this distributor for about 15 years and the benefits to our company far exceeded our wildest expectations. Some of these benefits were:
When we started using this distributor, Bill Richards was talking about inserting a float valve between a thermal expansion valve and distributor to remove the flash gas and feed solid liquid into the coil. Rigidbilt, like other coil manufacturers, reduced their "Fl.-Recirc" ratings by about 15 percent for TXV rating. If we could eliminate the flash gas, coil manufacturers could increase their TXV ratings and have only one coil capacity rating: Fl.-Recirc-TXV. This would be a huge benefit to our entire industry. The configuration of this box distributor is well suited to such an operation with a minimum of labor and expense.
If you would like to discuss this further, you can contact me at firstname.lastname@example.org.
Publication date: 12/05/2005