4
DRISTEEM RTS HUMIDIFIER SDU INSTRUCTIONS
INSTRUCTIONS
MOUNTING SDU-I-RX AND SDU-E-RX
SDUs can be mounted on a wall directly above a RTS humidifier cabinet, 18" above any other DriSteem humidifier, or
mounted on a wall remote from the humidifier.
• Installation must comply with governing codes.
• See www.dristeem.com for interconnecting piping requirements.
• Provide at least 6" (150 mm) clearance on each side of the SDU.
• Field wiring is required to connect the SDU fan and airflow proving switch terminals to humidifier electrical panel
terminals. Refer to the wiring diagram in the package shipped with your unit. Minimum wire size for field wiring is
18-gauge (1.5 mm
2
) stranded wire.
• Two 3/8" lag bolts (M10 × 50 mm coach screws) are provided with each fan unit.
• When mounting on a stud wall (studs 16" [406 mm] on center), locate studs and position lag bolts (coach screws) in
place so that each of the two lag bolts (coach screws) centers on a stud. Mark hole locations and predrill ¼" (6 mm)
diameter pilot holes for a 3/8" × 2" lag bolt (M10 × 50 mm coach screw).
• For hollow block or poured concrete wall mounting, drill appropriate pilot hole for two 3/8" (M10) toggle bolts or
two 3/8" (M10) machine bolt lead anchors (expansion bolts). Secure SDU frame in place.
• To provide power to the SDU used with 208V/240V/single-phase and 208V/three-phase humidifiers, run a neutral
line with the power supply to provide a 120V circuit for the fan.
• On a call for humidity, the humidifier begins producing steam, and the start relay energizes the SDU blower. When
the call for humidity is satisfied, the Vapor-logic controller keeps the blower running to disperse residual moisture
using a time delay.
NOTES:
Failure to follow the recommendations in this section can result in excessive back pressure on the humidifier. This will
result in humidification system problems including leaking gaskets, blown water seals, erratic water level control, and
spitting condensate from dispersion tubes.
SDU-I-RX: INSTANT, INTERNAL ABSORPTION, UP TO 30 LBS/HR
SDU-I-RX (Space Distribution Unit Internal Absorption) disperses humidity with no visible vapor trail or wetness, making
it ideal for use in finished spaces. The SDU-I-RX fan mixes room air and steam to ensure complete absorption before
discharge as humidified air.
IMPORTANT:
For visible vapor to be absorbed completely within the SDU-I-RX unit before being discharged as humidified air, room
air must be 45% RH or less. Trying to maintain greater than 45% RH will cause visible vapor and potential for moisture
collection on the discharge grille.
Mounting