Lochinvar WH 55-399 Required Pipe Sizes, Hydronic piping, Number of Units, Model, Notice Notice

Installation & Operation Manual

6 Hydronic piping

Figure 6-9Multiple Boilers - Multiple Temperature - DHW Piped as a Zone

			Number of Units
Model	2	3	4	5	6	7	8
		Required Pipe Sizes
55	1-1/4"	1-1/2"	1-1/2"	2"	2"	2"	2"
85	1-1/4"	1-1/2"	2"	2"	2"	2-1/2"	2-1/2"
110	1-1/2"	2"	2"	2-1/2"	2-1/2"	2-1/2"	3"
155	2"	2"	2-1/2"	2-1/2"	3"	3"	4"
199	2"	2"	2-1/2"	3"	4"	4"	4"
285	2-1/2"	2-1/2"	3"	4"	4"	4"	5"
399	2-1/2"	3"	4"	4"	5"	5"	5"

	PRESSURE	TEMPERATURE	TEMPERATURE	TEMPERATURE	WIRES TO
BACKFLOW	REDUCING VALVE	LOOP #1	LOOP #2	LOOP #3	LOOP
PREVENTER	PRESSURE				SENSORS
	GAUGE

MAKE
UP	MIXING VALVES
WATER	(TYPICAL)
	SYSTEM
	SUPPLY
	SENSOR
	AIR SEPARATOR
	EXPANSION
	TANK
	MAY SUBSTITUTE
	LOW LOSS HEADER

BALL VALVE

(TYPICAL)

DRAIN POINT

(TYPICAL)

Y-STRAINER (RECOMMENDED)

BOILER

CIRCULATOR

NOT TO EXCEED 4 PIPE DIA OR MAX. OF 12" APART

	24V SIGNAL TO
	MIXING VALVES
120VAC TO PUMPS
DOMESTIC	MULTI-TEMP TO
	LOOP CONTROL
HOT WATER
CIRCULATOR
FLOW	SHIELDED CABLE TO
	BOILER CONTROL
CHECK
	HOT WATER	ANTI-SCALD
VALVE
	OUT	MIXING VALVE
		COLD
		WATER
		IN

PRESSURE

RELIEF

VALVE

BOILER BOILER

CAUTION

NOTICE

NOTICE

	DRAIN		INDIRECT
UNION		TEMPERATURE /	DHW TANK
(TYPICAL)		PRESSURE GAUGE
			IMG00191

Mixing valves are required for the protection of low temperature loops.

Please note that the installer is responsible for ensuring DHW prioritization when piped as a zone.

Please note that these illustrations are meant to show system piping concept only, the installer is responsible for all equipment and detailing required by local codes.

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