Publix Supermarket at Melrose in Nashville TN will soon be operating the first CO2 refrigeration system of its kind in the chain’s Nashville Metro area. T & O Refrigeration is handling the installation and Clark Crane the lifting of the machine house into its 3rd story rooftop location at Berry Hill.
Next week in Nashville – Free Seminar – Reserve Your Seat!
SIGN UP NOW BEFORE THE SEATS ARE ALL SOLD!
Suppose you are testing a Copeland 3D (Discus) compressor and your ohmmeter registers OL from line to line on all of the 3-phase legs. The compressor is cold so you determine that the compressor is not off due to an overheat/internal thermostat trip. Your early assessment is that the compressor is bad and must be replaced. You call your supervisor who immediately sees a red flag when you say all 3 windings are open. It may be a defective “inherent protector”. This happened to a service tech that I supervised a few years ago. And it did have a bad protector. Please see the following photo and wiring diagram for more information on how this all works and the numbers needed to obtain a replacement inherent protector. By the way, this part is located beneath the terminal plate and is mounted just above the motor windings in order to detect the first possible overheat situation.
Get ready Nashville for the much anticipated and most requested HVACR training experience.
Continue to monitor this website for information regarding registration for this seminar.
One of the ways to assure that a customer’s case is performing as it should is to test the airflow. One of the best ways to do this is with a test instrument that measures feet per minute as illustrated.
Be sure to measure the airflow at the case discharge air outlet as illustrated below:
The manufacturer recommends that the best time to measure the case airflow is during the warmest time during defrost as the case cycle is terminating.
Below is a manufacturers chart detailing an example of a case specifications including the case design average air flow. Without the proper air flow, the case temperature will not reach the desired set point and the product integrity will suffer.
Members and guests got to check a fractional hp compressor for good/bad windings at the June 2017 Regular Monthly Meeting at the Middle TN Chapter. Jayson Goff, CMS was the seminar leader and had just returned from a winning battle over Stage 4 cancer. By the way, the compressor was deemed terminally ill by Larry Lynn, CMS and Doug Drake, CM, due to bad terminals. 😀