WIRING
OPTION 12: VisionPRO IAQ controlling 2 TrueSTEAM humidifiers
6
5
4
3
2
On
Off
1
AFS Monitor Recommended
M32914
AFS
TrueSTEAM 1
FURNACE
M33057
COMMUNICATION LED
COMMUNICATION
TERMINALS
24 VAC
TH9421C1004
THM5421C1008
THE YTH9421C1002 KIT INCLUDES THE TH9421C1004 VISION-PRO IAQ THERMOSTAT AND
THE THM5421C1008 EQUIPMENT INTERFACE MODULE. THE YTH9421C1010 KIT INCLUDES
THE TH942C1004 VISION-PRO IAQ THERMOSTAT, THM5421C1008 EQUIPMENT INTERFACE
MODULE, AND C7089U1006 OUTDOOR SENSOR.
A DOUBLE-POLE RELAY SUCH AS THE R8228D1018 IS REQUIRED.
AN AIR-FLOW SWITCH IS RECOMMENDED. IF AN AIR FLOW SWITCH IS NOT USED THERE
DOES NOT NEED TO BE A WIRE ATTACHED TO C ON THE TrueSTEAM AND THE #4 DIP
SWITCH NEEDS TO BE SET TO “ON”.
GT IS NOT REQUIRED FOR THIS APPLICATION. SINCE THE VISIONPRO IAQ THERMOSTAT
DOES NOT HAVE A Y/G INTERCONNECT, PARALLEL WIRING CAN BE DONE (AS SHOWN).
HM506, HM509, OR HM512 TrueSTEAM HUMIDIFIERS CAN BE USED.
CONFIGURE THE THERMOSTAT TO HUMIDIFY INDEPENDENT OF FAN (INSTALLER SETUP
374 SET TO 3).
1
2
3
4
5
6
TrueSTEAM 2
1
6
3
2
1
4
4
5
CONV
HP
TrueSTEAM Humidification System 69-2285—01
42