Emerson ZX, User Manual

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The following assumes that the installing contractor has confirmed the ZX unit was leak free on
arrival (refer to Section 4.0). That step is important before proceeding with the following.
Leak checking is particularly important for field-connected systems. Typically field systems lose
as much as 20-30% of their refrigeration charge annually. This is not only an unnecessary
expense but it is also damaging to the environment.
Compressor oil can be lost at the same time as refrigerant and eventually lead to compressor
failure. ( Time spent on leak testing will likely reduce the time you need to spend to on the
evacuation process).
Ensure that all service valves are open during the leak checking process. It is now important to
re-check all joints within the unit as well as the external joints you have made. Remember we are
aiming at a high degree of vacuum in the next process, so the unit must be leak free first. (Please
refer to Fig.8) for the connection points described below;
10.1 Initial Pressure Testing (by vacuum and nitrogen)
Step-by-Step :
•
Use a 4-port gauge manifold with 3/8” hose and connections to the vacuum pump. The
vacuum gauge dose not need to be connected for this part of the process.
• Then connect gauge lines to both ZX unit service valves with the schraeder cores removed
from valve connections and depressors removed from gauge lines- this is important!
Hose with Schraeder Hose without schraeder Schraeder valve with
valve Depressor valve Depressor core removed
Fig 17 Schrader Valves with and without Depressors
•
This next step is to remove any non-condensable that may have entered the system during
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