White Rodgers 1127 installation instructions Installation Cont, Wiring

INSTALLATION CONT.

Convenient Installation – May be mounted vertically, horizontally, or on an angle. Will not affect operation of control.

Pipe Insulation Should Cover Shield Containing Element.

WIRING

All wiring should be done according to local and national electrical codes.

RED BLUE

COMMON

OPEN ON RISE

OF TEMPERATURE

Refer to the wiring diagram supplied by the boiler or burner manufacturer, or to the suggested circuits included with the primary control. The information below shows the terminals to use for the various applications.

WHITE	Limit Control: When used as either a high limit control or as a
	low limit control, use the open-on-rise terminals (red and blue).

CLOSE ON RISE

OF TEMPERATURE

This control has a single-pole, double-throw snap action switch. The top left-hand terminal (red) is the common terminal. The top right-hand terminal (blue) has open-on-rise switch action. The bottom centre terminal (white) has close-on-rise switch action.

Circulator Control: When used as a circulator control, use the close-on-rise terminals (red and white).

Combination Low Limit and Circulator Control: For this application, all 3 terminals are used. The wiring diagram below shows a typical circuit for a hot water system having a boiler with tankless domestic coil.

Diagram for Boiler with Tankless Domestic Coil		3-WIRE THERMOSTAT			TYPE 668 OIL
HIGH	24 VAC		(USE W-B FOR	BURNER CONTROL
		2-WIRE THERMOSTAT)		(LINE VOLTAGE)
LIMIT	GAS VALVE

		TRANS.		HOT	LINE	N		IGNITION
									TRANS.
		R
X	X	Diagram for
		Gas-Fired System				X	X		BURNER
		B	1	2
		W							MOTOR
		JUMPER	3	4
						JUMPER			CIRCULATOR
									MOTOR
								R	B
									W
							HIGH	TYPE 1127
							LIMIT	LOW-LIMIT
The R-B contacts of the low-limit circulator control maintain								CIRCULATOR
								CONTROL
domestic hot water at the desired temperature year-round.

When the thermostat calls for heat, the burner starts. The circulator also starts if the R-W contacts of the low-limit circulator control are closed.

If excessive boiler temperature causes the high limit to open, the circulator continues to run but the burner shuts down until the high limit recloses.

If low boiler temperature causes the R-W contacts of the low- limit circulator control to open, the burner stays on but the circulator stops until the R-W contacts reclose.

When the thermostat is satisfied, the circulator stops. The burner also shuts down if the R-B contacts of the low-limit circulator control are open.

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