White Rodgers 1131 Wiring Cont, Setting The Control, Controls With Adjustable Differential

WIRING (CONT.)

Diagram For Gas Or Oil Fired System With Tankless Domestic Coil

3-WIRE	TYPE 668 OIL
THERMOSTAT
(USE W-B FOR	BURNER CONTROL
2-WIRE THERMOSTAT)	(LINE VOLTAGE)

24 VAC

GAS VALVE HIGH LIMIT

TRANS.

X X

	TYPE		HOT	LINE	N		IGNITION
							TRANS.
	809 RELAY
R
B	1	2			X	X	BURNER
W							MOTOR
JUMPER	3	4
									CIRCULATOR
							R	B	MOTOR
							W
						HIGH	LOW LIMIT
						LIMIT	CIRCULATOR

The R-B contacts of the low limit-circulator control main- tain 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.

Controls With Adjustable Differential

1.Insert a screwdriver in the centre slot and turn the dial until the right hand indicator “B” points to the lowest temperature of the cycle.

2.Turn the differential adjusting screw “C” until the left hand indicator “D” points to the highest temperature of the cycle.

The left-hand indicator points to the temperature at which the contacts open on high limit and low limit applica- tions. On circulator applications, the left-hand indica- tor points to the temperature at which the circulator will start.

On combination low limit and circulator applications,

the left-hand indicator points to the temperature at which the low limit stops the burner and permits the circulator to run.

SETTING THE CONTROL

Controls with a Fixed Differential

Insert a screwdriver in centre slot “A” and turn the dial until the fixed indicator “B” points to the highest desired tem- perature of the cycle.

The fixed indicator points to the temperature at which the contacts open on high limit and low limit applications. On circulator applications, the fixed indicator points to the temperature at which the circulator will start.

On combination low limit and circulator applications, the fixed indicator points to the temperature at which the low limit stops the burner and permits the circulator to run.

“B” FIXED INDICATOR

“B” FIXED INDICATOR	“A” ADJUSTING
	SLOT

“A” ADJUSTING
SLOT	“C” DIFFERENTIAL
	ADJUSTING SCREW
	“D” MOVABLE INDICATOR

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