Wiring Guides - Honeywell Prestige THX9321 System Installation Manual

THX9321/9421 Prestige
_ IAQ and RF ElM
Thermostat wiring guides -- Prestige THX9321
Typical wiring of a 3-heat / 2-coot heat
pump system with one transformer
Transformer _D R24 C
®U2
MCR32948
Typical wiring of a 3-heat / 2-cool heat
pump system with two transformers
®R
© u2
OR ZONE PANEL _} U2
Backup Beat _ R ............ i..............................
Transformer _ C MCR32950
Typical wiring of a 2-heat / 2-cool con-
ventional system with one transformer
Transformer _A4CR24 C '
©Re
oR _
®W
Qw
®U2
MCR32949
Typical wiring for geothermal radiant
heat, geothermal forced-air and back-
up heat with one transformer
Transf ..... __
I©c
i©mo o_
I®R
i
EOTHERMAL IQ U1
- :2-
i
HEAT i@U =_"
UA STAGE I '(_ U 2 T _
MCR32951
U1 and U2 terminals are dry contacts.
A L/A terminal sends continuousoutputwhen thermostat is set to EM HEAT modeexceptwhen set up for Economizeror TOD.
See Economizerwiring section,
A U1 or U2terminals mustbe used for geothermal radiant heat (ISU2010). Thermostatallows 2 stages of radiant heat--
geothermal(stage 1) and boiler (stage2),
_I_ "U"terminals are normallyopen dry contactswhen set up for geothermal radiant heat.Youmust install a field jumper if radiant
heat is powered by system transformer.Do NOTinstall a field jumper if radiant heat has its own transformer.
A Removejumper if using separate transformers,
Connectthe THP9045Wiresaver Moduleto the K terminal in heating/cooling applicationsthat do not havea common wire
at the thermostat,The K terminal cannot be used in heat-onlyapplications.See THP9045 installationinstructionsfor more
information.
13 69-2490--03