Connect The Gfx4 Humidistat For On/Off Operation; Modulating Operation; Pressure, Safety, And High Limit Switches (Field Supplied) - GeneralAire 5500 Manuel D'installation Et D'utilisation

Contact AB-AB:
• Closed: humidifier enabled to produce steam (production
starts when humidistat closes).
• Open: steam production is immediately stopped.
• The remote ON/OFF contact is usually a series of external
potential-free contacts that enable the humidifier to produce
steam when all of them are closed, indicating the duct/AHU
is ready to accept steam. Connect the 12502 Pressure Switch
NO and C terminals to the AB-AB contacts.
For Example:
• Fan contact closes when fan is running.
• Downstream cooling coil contact closes when coil is off, etc.
Contact IN-GND:
• Closed: steam production starts if contact AB-AB is closed.
• Open: steam production is stopped after 5 seconds.
3.13 CONNECT THE GFX4 HUMIDISTAT FOR
ON/OFF OPERATION
Reference Fig 3.t See the GFX4 installation manual for
complete instructions.
1. Remove the humidistat from the base, squeeze the
louvered base at the top and bottom. To remove the
humidistat from the wall, lift up on the humidistat and
pivot top away from wall.
• Before wall mounting, remove the black foam gasket.
• Before return air duct mounting, remove the breakout
piece.
2. If return air duct mounting, route wires between humidistat
and base.
3. Mount the sensor outside the house, at least 4 feet away
from any exhaust vent. If in air intake, place 1 foot or closer
to outside wall. Place at least 6" higher than possible snow.
Do not mount on south side of the house or in direct
sunlight. Do not route sensor wire near high voltage wires.
4. Connect the GFX4 and steam humidifier to the HVAC
equipment as shown in Fig. 3.s. to activate the HVAC
blower.
JUMPER
R C G
HVAC EQUIPMENT
Fig. 3.t

3.14 MODULATING OPERATION

Connect an external 0 to 10 VDC modulating input between
terminals IN-GND. Connect any safety switches (high limit, air
flow switch, remote ON/OFF) in series to terminals AB-AB. If
no safety switches are used, then a jumper must be installed
between AB-AB. DO NOT apply any voltage to AB-AB.
3.15 PRESSURE, SAFETY, AND HIGH LIMIT
SWITCHES (FIELD SUPPLIED)
Recommended as an additional precaution. Remove the
jumper between terminals AB-AB and connect any simple
high limits air flow switch (suggest part HC-201; GFI #7520
or similar); a pressure switch (suggest part 12502; GFI #7021
or similar), and remote contacts in series to terminals AB-AB;
otherwise, if no such dry contacts are available, the jumper
must remain in place between terminals AB-AB. DO NOT
apply any voltage to AB-AB. Thread the control wiring through
the bottom of the unit, and the strain relief (see photo at top
of previous page), and then up the side of the control module
to the top right wiring terminal blocks. Connect the control
wiring to the control wiring terminal blocks found at the top
right side of the control module. See Fig 3.u.
PRESSURE
SWITCH
REF
OUT
Fig. 3.u
14
N2
G ND
N1
AB
AB
G ND
IN
NO
C
NC
C
NO
GND
24V
STEAM HUMIDIFIER