Lochinvar COPPER-FIN 497 - 2067 - Manual (Page 53)

7
Domestic water heaters
(continued)
TABLE 7C
Pipe Sizing Chart
497 - 747 987 - 2067
Number of
Units
Common Pipe
Size (Min.)
Number of
Units
Common Pipe
Size (Min.)
1 2'' 1 2 1/2''
2 3'' 2 4''
3 3'' 3 4''
4 4'' 4 5''
5 5'' 5 6''
6 5'' 6 6''
Water chemistry
The required temperature rise and the standard pump sizing
are based on the heating of potable water with a hardness
of 5 to 25 grains per gallon and a total dissolved solids not
exceeding 350 ppm. Consult the appliance manufacturer
when heating potable water exceeding these specifications.
Heating of high hardness and/or high total dissolved solids
water will require a larger circulating pump, an optional
cupro-nickel heat exchanger and a revised temperature rise
specification based on the water chemistry of the water to
be heated.
Water with a hardness of less than 5 grains per gallon will
usually have a low pH which can be aggressive and corrosive
causing non-warrantable damage to the heater, pump and
associated piping. Corrosion due to water chemistry generally
shows up first in the hot water system because heated water
increases the rate of corrosive chemical reactions.
Pipe size requirements
Table 7B, pipe sizing chart provides the minimum pipe size
for common manifold piping to ensure adequate flow.
Required temperature rise
Based on heating potable water with a hardness of 5 to
25 grains per gallon and/or total dissolved solids not
exceeding 350 ppm, see Water Chemistry, this page.
Installation & Service Manual
Circulating pump
1. The water heater must be connected to a properly sized
pump that circulates water between the heater and
storage tank.
2. The pump is sized to heater input and water hardness.
Care should be taken to size the pump correctly. See
Water Chemistry, this page.
3. The water heater is equipped with a factory-supplied
pump delay system in accordance with the requirements
of the latest edition of ASHRAE 90.1.
4. Lubricate the pump to the manufacturer’s
recommendations. Pump damage due to inadequate
lubrication is non-warrantable.
5. Standard water heaters are furnished with the following
circulating pump. Mount the pump on the unit’s inlet
water connection.
Models 497 - 747
1/4 HP, 120 VAC, 5.8 Amps
Models 987 - 2067
1/2 HP, 120 VAC, 7.4 Amps
This pump is sized based on installation of a single storage
tank and heater in close proximity. If the number of fittings
and straight pipe exceeds the quantities shown in this section, a
larger pump will be required.
The standard pump selection is based on the following pipe and
fittings from the unit to the storage tank:
• 6 90° elbows
• 2 unions
• No more than 45
feet of straight pipe.
• 2 ball valves
• 1 cold water tee
NOTICE
For every elbow and tee in excess of those shown
above, deduct 5 feet from maximum allowable
straight pipe in heater to tank circulating loop.
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