Honeywell HE440A - Page 6

HE440A, HE480A STEAM POWER HUMIDIFIER
68-0265EF-1 6
Equipment Fan Applications
CAUTION
Moisture Condensation and Wiring Hazard.
Moisture can destroy furnace electronic controls
and miswiring can burn out electrical components.
Do not alter any of the heating and cooling system
functions.
Be sure to wire only the system fan.
See wiring diagrams in Fig. 7-9 for typical applications.
Fig. 7. Typical wiring diagram for humidifier in single-
speed fan applications without air conditioning
(switching through external relay).
Fig. 8. Typical wiring diagram for humidifier in dual-speed
fan applications with air conditioning.
Fig. 9. Typical wiring diagram for humidifier in single-
speed fan applications without air conditioning
(switching through G contactor).
The humidifier has a sealed switch with a thermostatic sensor
that is designed only for low voltage applications. The sealed
switch is attached to the humidifier wall and is wired through a
thermal switch fan plug. The switch is preset to turn on the fan
when the water temperature is 170°F (76°C) and turn off the
fan when the water temperature falls below 120°F (50°C).
Heat Pumps
No wiring diagrams can be suggested due to the many
variations and wiring complexity of heat pumps. If humidifier
control fan operation is desired, be sure to design a safe
control circuit using equipment diagrams and tracing the
equipment wiring.
In heat pump applications, a fan sail switch must be installed
due to almost continuous system fan operation. Wire the fan
sail switch in series with the low voltage humidity control
circuit so the humidifier is on only when the fan is operating.
(In most cases, the humidifier does operate in conjunction
with the system fan.)
NOTE: Wiring the humidifier to operate with the system fan
limits the humidification output.
Variable Speed Motors
Continuous speed on variable speed motors may need to be
increased to provide enough air flow to prevent condensation
inside the ductwork. Minimum recommended air flow, under
most conditions, would be 400 cfm (680 cmh) in the duct
where the humidifier is mounted.
Water Treatment
Use cable (provided) to connect plug end to humidifier and
wire to solenoid using wire nuts (provided). See Fig. 10.
1
1
2
3
STEAM
HUMIDIFIER
TRANSFORMER
NOT SUPPLIED
EQUIPMENT
BLOWER
N.O.
BLACK
WHITE
RELAY NOT
SUPPLIED
FAN LIMIT CONTROL
L
2
L
1
(
HOT)
24V WIRING.
2
R8222D1014 RECOMMENDED.
3
AT2DA1123 RECOMMENDED.
M2033
1
FAN
WIRING
SOLENOID
WIRING
HUMIDISTAT
TERMINALS
1
STEAM
HUMIDIFIER
TRANSFORMER
NOT SUPPLIED
EQUIPMENT
BLOWER
LOW
SPEED
N.C.
N.O.
COOL
HEATBLACK
WHITE
RELAY NOT
SUPPLIED
HIGH
SPEED
G CONTACTOR
FAN LIMIT CONTROL
L
2
L
1
(
HOT)
M2033
2
FAN
WIRING
SOLENOID
WIRING
HUMIDISTAT
TERMINALS
1
24V WIRING.
2
2
R8222D1014 RECOMMENDED.
3
3
AT2DA1123 RECOMMENDED.
1
2
1
2
STEAM
HUMIDIFIER
EQUIPMENT
TERMINAL
STRIP
EQUIPMENT
BLOWER
G CONTACTOR
L1 L2
24V WIRING.
INSTALL JUMPER FROM R TO R
C
.
M20333
FAN
WIRING
SOLENOID
WIRING
H
UMIDISTAT
TERMINALS
R
R
C
G
W
C