Leak Checking For Unit And Field-Installed Piping - Vertiv Liebert CW Series Installer And User Manual

NOTICE
Risk of no-flow condition. Can cause equipment damage.
Do not leave the water/coolant fluid-supply circuit in a no-flow condition. Idle fluid allows the collection of
sediment that prevents the formation of a protective oxide layer on the inside of tubes. Keep unit switched On
and water/coolant fluid-supply circuit system operating continuously.
Refer to the appropriate piping general-arrangement schematics for your system for the recommended, field-installed
hardware such as shut-off valves. See Table 5.1 on page 31.
• Use copper piping with a brazing alloy with a minimum temperature of 1350°F (732°C), such as Sil-Fos. Avoid
soft solders, such as 50/50 or 95/5.
• Follow local piping codes and safety codes.
• Qualified personnel must install and inspect system piping.
• The water/glycol-cooled system will operate in conjunction with a cooling tower, city water or drycooler.
• Contact a local water consultant regarding water quality, corrosion protection and freeze-protection
requirements.
• Install manual shut-off valves at the supply and return line to each indoor unit to permit routine service and
emergency isolation of the unit.
• Install a monitored, fluid-detection system that is wired to activate the automatic closure of field-installed
coolant-fluid supply and return shut-off valves to reduce the amount of coolant fluid leakage and consequential
equipment and building damage. The shut-off valves must be sized to close-off against the maximum coolant-
fluid system pressure in case of a catastrophic fluid leak.

4.2.1 Leak Checking for Unit and Field-installed Piping

The fluid systems in the Liebert® CWare factory-checked for leaks and may be shipped with an inert-gas holding charge.
At installation, check all fluid circuits for leaks.
NOTE: We recommend isolating the unit with field-installed shutoff valves during leak checking of
field-installed piping. When the units are included in a leak test, use of fluid for pressure testing is
recommended. When pressurized gas is used for leak testing the unit, the maximum recommended
pressure is 30 psig (207 kPa) and tightness of the unit should be verified by pressure decay over time,
(<2 psig/hour [13.8 kPa/hour]) or sensing a tracer gas with suitable instrumentation. Dry seals in fluid
valves and pumps may not hold a high gas pressure.
4 Piping Requirements
37