Honeywell TrueSTEAM HM612A1000/U Installation Manual page 67

B: Advanced Steam Humidifier Wiring
OPTION 13: Prestige IAQ controlling 2 Steam Humidifiers
THM5421R1005
IAQ
DEVICE
SENSOR TYPE
ON
OFF
AFS MONITOR RECOMMENDED
A DOUBLE-POLE RELAY SUCH AS THE R8228D1018 IS REQUIRED.
1
AN AIR-FLOW SWITCH IS RECOMMENDED. IF AN AIR FLOW SWITCH IS
2
NOT USED THERE DOES NOT NEED TO BE A WIRE ATTACHED TO C ON
THE STEAM HUMIDIFIER AND THE #4 DIPSWITCH NEEDS TO BE SET TO
"ON".
GT IS NOT REQUIRED FOR THIS APPLICATION. SINCE THE PRESTIGE IAQ
3
THERMOSTAT DOES NOT HAVE A Y/G INTERCONNECT, PARALLEL WIRING
CAN BE DONE (AS SHOWN).
HM609 OR HM612 STEAM HUMIDIFIERS CAN BE USED.
4
THE U1, U2, OR U3 CONTACTS CAN BE CONFIGURED TO CONTROL A
5
HUMIDIFIER. IN THIS DIAGRAM THE 1 TERMINALS ARE USED.
CONFIGURE THE THERMOSTAT TO HUMIDIFY INDEPENDENT OF FAN
6
(INSTALLER SETUP 374 SET TO 3).
Steam Humidifier System 69-2285—11
5
2
1 3 4 5 6
THX9421R5005
5
6
FURNACE
1
3
3
STEAM 4 STEAM
HUMIDIFIER 1 HUMIDIFIER 2
AFS
2
M33058B
65