WIRING
WIRING BASICS: CONFIGURATION 1
When using a thermostat with integrated
humidity control (such as VisionPRO IAQ
or Prestige):
Thethermostatispoweredbythe•
systemtransformer.Inthisconguration,
thethermostatmusthavepoweror
TrueSTEAMwillnotbeableto
producesteam.
Becausethethermostatknowswhenthe•
systemtransformerhaspower,setDIP4
toUP,sothatitisnotlookingforanRinput
fromthesystemR.
WIRING BASICS: CONFIGURATION 2
When using a humidistat separate from the
thermostat (such as H8908 or TrueIAQ):
TrueSTEAMgenerallysuppliespower•
tothehumidistat.Inthisconguration,
TrueSTEAMmustmonitorHVACsystem
powertodetermineifhumidityisallowed.
LeaveDIP4intheDOWNposition(factory•
setting),andwiretheHVACsystemRand
CtotheTrueSTEAMRandC.TrueSTEAM
willverifypowerispresentbeforeallowing
steamproduction.
Thermostat with
Humidity Control
HVAC System
Tr ueSTEAM
1
HUM
HUM
2
3
R
C
M29615
Humidity Control
HVAC System
TrueSTEAM
HUM
HUM
R
C
M29616
Note:Thisimageisnotacompletewiringdiagram.Itonlydepictspowermonitoring.
See “Wiring the TrueSTEAM” on page 19.
Note:Thisimageisnotacompletewiringdiagram.Itonlydepictspowermonitoring.
See “Wiring the TrueSTEAM” on page 19.
TrueSTEAMHumidicationSystem69-2285EF—01
15