Lochinvar SNA500-125 Diagrams, Installation & Service Manual, 1 Ladder Diagram, Pump, Box Depicts

TM

Installation & Service Manual

14 Diagrams

Figure 14-1Ladder Diagram

120VAC				JUNCTION BOX			NEUTRAL	GROUND
TERMINAL STRIP						TERMINAL STRIP
120V SUPPLY "L"						120V SUPPLY "N"
	PUMP					GND
	RELAY			DHW		DHW
	4 3			PUMP "L"		PUMP "N"
					DHW
				TERMINAL	PUMP	TERMINAL
				STRIP		STRIP
	INTEGRATED CONTROL				PUMP
X1-6	F5			X1-3	RELAY COIL
					2	1
	5A		DHW PUMP
			RELAY
X1-8								BOX DEPICTS
								OPTIONAL ITEMS
						BLOWER
	F4
				X1-1		1	2	LOW VOLTAGE
JUNCTION	3.5A
			BLOWER					120 VAC
BOX
	F3		RELAY			3
								HIGH VOLTAGE
	1.25A
	120 VAC			X1-5		JUNCTION BOX	CONNECTION
X5-7	F2			X6-8		CN2-4	BOARD
X6-7	3.5A	24 VAC		X6-3		CN2-10
X6-2
	CONNECTION
CN2-6	BOARD		CN5-1			CN5-2		INTEGRATED
						LWCO
								CONTROL
CN2-12					CN5-3	CN5-4		CN2-11 X6-9

			CONNECTION			LOW GAS		HIGH GAS
MANUAL RESET				BOARD		PRESSURE		PRESSURE
HIGH LIMIT	X5-14	X6-4 CN2-5			CN4-6		SWITCH	SWITCH	CN4-3	CN2-3 X6-5

	INTEGRATED
	CONTROL			INTEGRATED
				CONTROL
	DISPLAY
				EXTERNAL	2
				LIMIT		CN2-9	X6-10
					1
	X3
		RIBBON CABLE			AIR PRESSURE
PC					SWITCH	X5-11
				X8
INTERFACE						X5-4
				BLOCKED
			X5-8
		S2		DRAIN
	INLET			SWITCH		X5-3
	SENSOR			AUTO RESET
			X5-1			X5-10
		S1		HI-LIMIT
	OUTLET
	SENSOR			GAS VALVE
		S3	X5-2			X2-2
	FLUE		X5-9
							GAS VALVE
	SENSOR
						X2-1	RELAY
	CONNECTION BOARD			BLOWER		1	X5-5
		CN4-11 X3-1
RUN-TIME	3	CN4-12	X3-3			2	X5-13
CONTACTS
	4	CN4-10	X3-4			4	X5-6
ALARM	5	CN4-4	X3-2			5	X5-12
CONTACTS
	6					TR1
						X1-7
				SPARK		FLAME ROD
				ROD
	CN4-1	CN3-8	X4-8

		TANK			S4
						CN4-4	CN3-6	X4-6		CAUTION	HIGH VOLTAGE SPARK LEAD
	SENSOR
						CN4-5	CN3-10	X4-10
EXTERNAL			+
				0-10V		CN4-2	CN3-4	X4-4	NOTES:
CONTROL			-
									1. Where possible, switches are shown without utilities (gas, water or
									electricity) connected to the unit. As such, actual switch states may
									vary from those shown on diagrams depending upon whether utilities
									are connected or a fault condition is present.
									2. See wiring diagram for additional notes.
											LADDER DIAGRAM
											LBL20026 REV A

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