15
Figure 15-1: Piping method recommended when
obstruction prevents dispersion tube from being
continuously pitched back to humidifier:
Drain Piping
A drain line should be extended from the skimmer
connection to a sanitary waste or suitable drain. If non-
metallic pipe or hose is used, it must be capable of
withstanding temperatures up to 212°F (100° C).
To prevent steam from escaping out the drain line, a
water seal must be provided in the drain line of sufficient
height to contain the pressure developed within the
humidifier and steam dispersion system. To determine
the proper height of the water seal, see table 16-1.
Make-up Water Piping
When non-metallic water piping is used, it must be rated to
withstand 212°F (100° C) or greater temperature. If not,
the final three feet (one meter) connected to the humidifier
should be metallic and should not be insulated.
As part of the fill valve assembly, the needle valve
restricts the rush of cold water entering the evaporating
chamber during the fill cycle. Cold water could drop the
chamber water temperature and collapse the steam. If the
rumbling sound occurs during the fill cycle, adjust the
needle valve to decrease the water fill rate.
The VAPORSTREAM
®
Model VLC has a one-inch (25
mm) internal “air gap”. However, local codes may require
a vacuum breaker.
PIPING METHODS
Figure 15-2: Piping method recommended when
humidifier must be mounted higher than the duct:
* Refer to local codes for drain pipe size requirements.
2" Per Foot
(165 mm/m) Pitch
5" (125 mm) Min.
Funnel or Floor Drain*
OM-699
Optional SST Tubing Tee
OM-698
Funnel or Floor Drain*
Obstruction
¾" (20 mm) Tubing
5" (125 mm)
Min.
4" (100
mm) Min.
