Fig. 337. Connecting a stage of heating or cooling to a universal relay (U1, U2, U3).
1 U1, U2, and U3 are normally open dry contacts when set up for a stage of heating or cooling.
2 You must install a field jumper if the stage of heating or cooling is powered by the system transformer. Do NOT install a field
jumper if the stage of heating has its own transformer.
U3
U3
U2
HEAT STAGE 3,
U2
COOL STAGE 3,
COOL STAGE 4 OR
U1
GEOTHERMAL
1
RADIANT HEAT
U1
2
RH
RC
R
24
VAC
C
131
®
VISIONPRO
TRANSFORMER
24
120
VAC
VAC
8000 WITH REDLINK™
68-0312—03