3
STS INSTALLATION, OPERATION, AND MAINTENANCE MANUAL
Tap/softened water STS humidifi er
Air gap
Water seal
Condensate return
Steam trap
Automatic steam valve
Open drain
Manual drain valve
Heat exchanger
Float valve water level control
OM-939
Notes:
• Drain piping material must be suitable for 212 °F (100 °C) water.
• See the piping drawings on Pages 22 through 25.
Humidifi cation steam outlet
Automatic steam valve
Boiler steam
Steam trap
Condensate return
Water seal
Air gap
Open drain
Manual drain or optional
motorized drain valve
Heat exchanger
OM-938
STS humidifi er with the RO/DI water option
OVERVIEW
Fill valve
Float rod
Float ball
VLC-OM-026
Humidifi ers using RO/DI water control water
level using a fl oat valve. An optional low-water
cutoff switch is available as a remote water
indicator.
mc_030910_1336-STS
Humidifi cation steam outlet
Probe water level control
Boiler steam
Product overview
Humidifi ers using tap or softened water control
water levels electronically using a three-rod
probe. The controller responds with the above
actions when the water level reaches each rod.
VLC-OM-030
Fill valve opens when
water level is below this
probe.
Low-water cutoff.
Pressurized steam to
heat exchanger is cut if
water level drops below
this probe (if steam to
STS heat exchanger
is controlled by
Vapor-logic).
Fill valve closes when
water level rises to this
probe.
mc_030910_1335-STS
FIGURE 3-1: STS HUMIDIFIERS
FIGURE 3-2: WATER LEVEL CONTROL
FOR TAP/SOFTENED WATER HUMIDIFIER
FIGURE 3-3: WATER LEVEL CONTROL
FOR RO/DI-WATER OPTION HUMIDIFIER
