Braeburn 2020NC Detailed Installer Manual page 5

Conventional Systems
Typical Wiring Configurations
NOTE: The "Installer Switch" option will be configured in the next step.
Heat Only or Millivolt
Set Installer Switch to CONV
Rh Power Connection
W1 Heat Relay (appears as W1/E on 2220NC)
1 HEAT / 1 COOL Single or Dual Transformer
Set Installer Switch to CONV
Rh 24 Volt AC Power (heating transformer) [note 2]
Rc 24 Volt AC Power (cooling transformer) [note 2]
W1 Heat Relay (appears as W1/E on 2220NC)
Y1 Compressor Relay
G
Fan Relay
C 24 Volt AC Transformer Common [note 1, 3]
2 HEAT / 2 COOL Single or Dual Transformer (2220NC Only)
Set System Type to CONV
Rh 24 Volt AC Power (heating transformer) [note 2]
Rc 24 Volt AC Power (cooling transformer) [note 2]
W1
Heat Relay Stage 1
W2
Heat Relay Stage 2
Y1
Compressor Relay Stage 1
G
Fan Relay
C 24 Volt AC Transformer Common [note 1, 3]
NOTES - Conventional Systems
[1] If batteries are installed the 24 Volt AC common connection is optional
[2] Remove factory installed jumper for dual transformer systems
[3] In dual transformer systems, transformer common must come from
cooling transformer
Provide disconnect and overload protection as required.
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