Liquid Line Solenoid Valve - Data Aire gForce Ultra Installation, Operation And Maintenance Manual

5.10.5 Liquid Line Solenoid Valve

Liquid line solenoid valve(s) (LLVS) are a standard feature on this unit. The LLSV are direct acting, NC
(normally closed; i.e. closed when de-energized) solenoid operated valve(s). This has the advantage
that the valve is closed when the system is not running and when the solenoid valve is not energized.
For this reason, an electrical power failure does not lead to any problems with the refrigeration system.
The primary purpose of a solenoid valve in a refrigerant liquid line is to helps prevent refrigerant migra-
tion (i.e., flow into the evaporator) during the OFF cycle.
NOTE: Charging to a full liquid line sight glass should never be the sole
means of determining the correct refrigerant charge. Other parameters such
as superheat, suction pressure, head pressure, sub-cooling and ambient
temperature are also important. A system charged to a clear sight glass is
often overcharged.
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