Wiring Guide

9
Sequence of Operation / Settings
• A demand occurs and closes RW (TT)
• Relay #1 and relay #2 both fire connecting the
common terminal to the NO terminal.
• If the factory installed jumper has not been
removed, the NO terminal of relay #1 will
deliver the hot leg of 120 VAC. Relay #2 has
dry contacts.
• The zone LED illuminates.
• The demand is satisfied and opens RW (TT).
• The relay contacts return to their normal
position (common to normally closed).
• The zone LED turns off.
Description of terminals
= Ground
N = Neutral (Common leg of 120 VAC)
L = Line (live leg of 120 VAC)
C = Common terminal
NO = Normally Open terminal
NC = Normally Closed terminal
Note: There is a factory installed jumper between the 120
VAC line (L) and the common terminal of relay #1 (C).
Thermostat terminals
R = 24 VAC
W = Heat call
C = Common of 24 VAC
WARNING: NEVER CONNECT R & C DIRECTLY,
this will be a direct short on the 24 VAC supply