Install Instructions

WIRING TO 24 VAC TRANSFORMER
For boilers using a standard 24 VAC transformer
BOILER SPECIFIC MODELS AND WIRE HARNESSES
Connect RED wire to hot side of 24 Volt boiler trans-
former (R). Connect WHITE wire to common side of
24 Volt boiler transformer (C). Connect the GREEN
wire to any suitable, unpainted ground screw.
Note: for operation of the control, the green wire
must be connected to a ground source electrically
common with boiler ground.
Cut-off the connectors and strip the ends of the two
yellow wires of the Model 1100 harness. Break into
the burner circuit between the hot side of the trans-
former (R) and other limit controls. Connect either
YELLOW wire to the hot side. Connect the other
YELLOW wire in series with other limit controls.
Important: The switch contacts of the low water cut-
off (yellow wires) must be wired in series with all
other limit and operating controls (as shown above).
Step
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Step
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1100H2
Including 45-348 Harness
Part No. Model Description
45-1100 1100 1100 with standard wire harness (cable 45-531-54)
45-1102 1100H2 1100 with wire harness for UTC intergrated control module
(cable 45-348)
45-1103 1100H3 1100 without wire harness
45-1105 1100H5 1100 with wire harness for Weil McLain Ultra, Lochinvar
Knight & Solution (cable 45-349)
45-1107 1100H7 1100 with wire harness for connection to vent damper plug on
boiler control (cable 45-353)
Note: Wire Harnesses are also sold separately (use cable part numbers above)