Raypak NH, 0133-4001 WH manual Piping - Domestic Hot Water Supply Heaters, General Specifications

PIPING - DOMESTIC HOT WATER SUPPLY HEATERS

GENERAL SPECIFICATIONS

UNI-TEMP 80 HOT WATER SUPPLY SYSTEMS

T = Temperature Rise, Degree F@GPM FLOW	MPS = Minimum Pipe Size, NPT
GPM = Gallons per Minute Flow	SHL = System Head Loss
P = Pressure Drop, Foot thru Heat Exchanger

The table above provides data for selecting in-line pumps for use in a Uni-Temp 80 system for a single heater and tank according to the following:

1.Flow rates are based on water hardness as measured in grains per gallon. Soft: 0-4 grains per gallon.

Medium: 5-15 grains per gallon.

Hard: 16 and over grains per gallon.

2.Maximum Flow Rates:

133	22 GPM
181-401	45 GPM
514-1826	90 GPM
2100-4001	200 GPM

3.Pressure drop values ( P and SHL) and minimum pipe sizes are for two-pass heaters.

4.Sizing based on heater and tank being placed 5 feet apart. The equivalent length of pipe valves and fittings in the system is as follows:

1-1/2" NPT = 70 Ft (181-401)	2-1/2" NPT = 80 Ft (926-1826)
2" NPT = 75 Ft (514-824)	3" NPT = 85 Ft (2100-4001)

Additional pipe fittings will increase the system head loss.

5.Select a pump based on the water hardness, flow, and system head loss.

6.If heater is more than two stories above the tank, consult the factory.

NOTE:

GPM flow rates are limited by maximum acceptable velocity through heat exchanger tubes. Heater models 514 through 1826 may be provided with an integral rear-mounted pump. This must be specified at time of order. The

integral pump will provide sufficient flow to meet the conditions listed in the table.

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