8
STEAM INJECTION INSTALLATION, OPERATION, AND MAINTENANCE MANUAL
PLACING A STEAM INJECTION HUMIDIFIER IN A PRIMARY/SECONDARY SYSTEM
(SEE FIGURE 8-1)
This type of system is commonly applied to facilities where most of the building
requires one humidity level (typically to meet comfort requirements) and
part of the building requires additional humidity. In Figure 8-1, the primary
humidification system is within the main air handling unit. The secondary
humidification system is located close to the point of steam discharge into the
secondary area.
Filter mixing box
Before humidifier:
50 °F (10 °C), 47% RH
Primary humidifier
location
After humidifier:
50 °F (10 °C), 60% RH
Room transmitter: 65
°F (18 °C), 50% RH
Secondary
humidifier
location
50 °F (10 °C)
60% RH
70 °F (21 °C), 30% RH
Primary area:
70 °F (21 °C),
30% RH
50 °F (10 °C), 60% RH
Secondary
humidified
area
VAV
box
Exhaust air
Outside air
Humidifier placement
OVERVIEW
FIGURE 8-1: PLACING A STEAM INJECTION HUMIDIFIER IN A PRIMARY/SECONDARY SYSTEM
