Humidifier Troubleshooting - Liebert PX018 Installer's/User's Manual

Figure 9.12 Canister plugs

9.4.4 Humidifier Troubleshooting

Terms Used in Humidifier Troubleshooting:
• FLA (Full Load Amps) are amps listed on the humidifier specification label.
• Short cycling occurs when the humidifier's "On time" is less than 10 minutes upon a call for
humidity. To correct short cycling, all humidifiers have a capacity adjustment that allows the
output of the humidifier to be reduced to as low as 20% of rated output, thus extending the "on
time" required to maintain output.
• Foaming can occur when the impurities already in water reach an excess concentration as a
result of boiling away water and continued boiling agitates the contained water. The humidifier
electronics are designed to prevent foaming, although in extreme cases water will foam with
little concentration, making it necessary to increase the drain time of the water contained in
the cylinder. Foaming is normally caused by short cycling, a restricted drain or back pressure.
The foam generated in these instances is conductive and may lead to false full-cylinder
indication if the level of the foam approaches the top of the cylinder.
• Back pressure is the restriction of steam flow caused by long steam runs, improperly sloped
steam lines, elbows changing the direction of steam flow from horizontal to vertical without a
drain leg, any plumbing detail allowing the accumulation of condensate, undersized steam line,
improper steam distributor, downward air flow onto the distributor causing excess static
pressure at the steam outlets, or high static pressure ducts (not probable). To overcome
excess static pressure in the duct, use a fill cup extension kit. In downflow applications, a
downflow distributor should be used, but in some cases the fill cup extension will also be
required.
Vertiv | Liebert® PDX™ and PCW™ Installer/User Guide |
Item Description
1 Cylinder pin
2 High-water sensor pin
∅
3
3
79