WIRING
Follow the diagram for control options 1 through 14 to wire the TrueSTEAM. Refer to the installation manual
provided with the control for additional instructions if needed.
OPTION 1: Dry-contact Mechanical
Humidistat Wiring
1
Make sure that the thermostat used
isolates Y from G. All Honeywell Prestige,
VisionPRO IAQ, VisionPRO, and Focus Pro
thermostats do this.
OPTION 2: TrueIAQ Wiring
1
Make sure that the thermostat used
isolates Y from G. All Honeywell Prestige,
VisionPRO IAQ, VisionPRO, and Focus Pro
thermostats do this.
2
For the TrueIAQ Installer Setup, set ISU
#25 to 3.
HVAC
RECOMMENDED
AIR FLOW SWITCH (AFS)
MECHANICAL
HUMIDISTAT
HVAC
POWER
MASTER
THERMOSTAT
HUM
HUM
G
Y
W
R
Rc
G
Y
W
R
C
TrueSTEAM - INTERNAL
24V
24V
HUM
HUM
C
GT
R
RT
GF
EXT
M24756
HVAC
ELECTRONIC
HUMIDISTAT
THERMOSTAT
HUM
HUM
24V
24V
G
Y
W
R
Rc
G
Y
W
R
C
24V
24V
HUM
HUM
C
GT
R
RT
GF
EXT
RECOMMENDED
AIR FLOW SWITCH (AFS)
M24757
HVAC
POWER
MASTER
TrueSTEAM - INTERNAL
Using the Correct Control Diagram
CAUTION: Voltage Hazard.
Before wiring to HVAC terminals, disconnect HVAC equipment power. Make sure TrueSTEAM
is not plugged in.
6
5
4
3
2
On
Off
1
AFS Monitor Recommended
M32913
6
5
4
3
2
On
Off
1
AFS Monitor Recommended
M32913
TrueSTEAM Humidification System 69-2285—01
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