THX9321/9421 P restige® IAQ and RF EIM
769-2490 —03
Install optional sensors
1 Mountthesensoronavertical
exteriorwall,atleast6inchesbelow
anyoverhang.Choosealocation
protectedfromdirectsunlight.
2 Placesensorsecurelyinbracket,
facingawayfromwall.

6

M28491
M28849A
[If no sensors are used, skip to Section 7.]

To install outdoor air sensor

To install indoor air sensor

1 Removethewallplateandmountit4
to6feetabovetheflooronaninterior
wall.Drill3/16-inchholesfordrywall,
7/32-inchforplaster.
2 Attachsensorsecurelytowallplateas
shown.

To install discharge/return air sensor

1 InstallthesensorbetweentheIAQ
equipmentandtheheating/cooling
equipment.Thesensorsmustbeinair
thatismixedwell(awayfroma-coil/
heatexchanger).
2 Drill1/4-inchholeforthesensor
probeandmountittotheductwork
withenclosedscrews.
3 ConnectwirestoS1orS2terminalsat
theEIM.
M32995
M32936
69-2490_B.indd 7 7/13/2011 1:41:52 PM