Table of Contents
Chapter 7 – Maintenance _____________________________________________________ 7-1
Preventive Maintenance Intervals __________________________________________________ 7-1
Maintenance Procedures __________________________________________________________ 7-2
How to clean the chamber interior and exterior _______________________________________________ 7-2
How to listen for abnormal noise or vibration ________________________________________________ 7-2
How to inspect the door seal ______________________________________________________________ 7-2
How to inspect the refrigeration machinery compartment _______________________________________ 7-3
How to check the low-stage refrigerant charge ________________________________________________ 7-3
How to check the high-stage refrigerant charge _______________________________________________ 7-3
How to verify the chamber performance _____________________________________________________ 7-4
How to inspect the electrical compartment. __________________________________________________ 7-5
How to clean the condenser. ______________________________________________________________ 7-5
How to verify the calibration. _____________________________________________________________ 7-5
Theory of Operation ______________________________________________________________ 7-7
Overview _____________________________________________________________________________ 7-7
Heating System ________________________________________________________________________ 7-7
Refrigeration System ____________________________________________________________________ 7-7
Troubleshooting _________________________________________________________________ 7-9
Refrigeration System Charging Instructions _________________________________________ 7-11
R-404A High-Stage Charge _____________________________________________________________ 7-11
R-508B Low-Stage Charge ______________________________________________________________ 7-11
Recommended Spare Parts _______________________________________________________ 7-12
Major Electrical Parts ___________________________________________________________ 7-13
Major Refrigeration Parts ________________________________________________________ 7-14
LN2 Parts (opt. 0018) ____________________________________________________________ 7-14
General Parts __________________________________________________________________ 7-14
EZ-Zone Limit Controller Setup Parameters ________________________________________ 7-15
Chapter 8 - Warranty ________________________________________________________ 8-1
Chapter 9 – Drawings ________________________________________________________ 9-1
