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This thermostat can be used with all millivolt and 24VAC heating and cooling systems. It
cannot be used with line voltage systems. This thermostat is digital and your desired heat or
cool temperatures can easily be set on the large screen with the +/- buttons on the front. A
minimum 4 minute off time protects heating and cooling systems from damage.
This thermostat uses a new technique called sequential staging for more comfort with
faster reaction to requested temperature changes. When using a heat pump with Aux heat, if
the heat pump cannot keep up and/or is
defective, remove jumper from position 8 and put
jumper on position 6 and the Aux heat will then
be your only source of heat. Be sure to restore it
to PUMP when the pump is again operational as
aux heat is more expensive than pump heat.
3M-22 Features
Wire Reference
Your Wires
Filtrete Terminal
R or V or VR RH and RC Single power for HEAT and COOL
RH or 4 RH Power for HEAT (RH not connected to RC)
RC RC Power for COOL (RH not connected to RC)
W W Heat control
W2 W2 2nd stage HEAT or heat pump auxiliary heat
? A 3rd wire for zoned hot water heat (see zoned)
Y Y COOL control
Y2 Y2 2nd stage COOL control
G or F G FAN control
C or X C Common 24VAC power (to power thermostat)
E Emergency heat (do not connect, tape off)
L System monitor (do not connect, tape off)
T Outdoor sensor (do not connect, tape off)
B or B Heat pump changeover (cool to heat, powered in heat)
O O Heat pump changeover (heat to cool, powered in cool)
B and O
SEE NOTE
PG
23
PG
24
B and O
NOTE: If
there are both
B and O wires
(Trane pump
products)
DO NOT
CONNECT B
to B terminal,
connect B to C
terminal