Lochinvar Power-Fin PF 1500, Руководство дизайнера

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GAS BLEEDS AND VENTS
All bleeds and vents from valves and
regulators are vented to the atmosphere,
outside of the fan pressurized inner
chamber. Local codes may require
routing of these bleeds and vents to the
atmosphere, outside of the building.
WATER CONNECTIONS
Inlet and Outlet Water Connections
For ease of service, install unions on inlet
and outlet of the water heater. The
connection on the unit marked "Inlet" should
be used for return water from the storage
tank. The connection on the header marked
"Outlet" should be connected to the inlet of
the storage tank. (See Appendix A for
Water Heater Piping Diagrams).
LOW WATER
TEMPERATURE DELIVERY
A number of water heating applications may
require delivered water temperature in a
system below 140°F. Systems such as
nursing homes and hospitals would be
examples of this type of system. A water
heating system that will be operated at less
than 140°F must use a mixing valve on the
outlet side of the storage tank in order to
ensure that the products of combustion do
not condense inside the combustion
chamber of the water heater. The mixing
valve allows the water heater to operate
above 140°F to protect from condensation,
while still allowing a delivery of colder water
to the system fixtures. Also inherent in this
design is the protection of occupants from
water containing bacteria such as
Legionella. Legionella can be significantly
reduced in the water storage vessel by
heating the water to a minimum of 140°F.
See Appendix A for piping details.
WATER VELOCITY CONTROL
IMPORTANT
To ensure proper velocity through the heat
exchanger, it is necessary to regulate the
temperature rise across the heat exchanger
from inlet to outlet. (This must be done on
initial installation and periodically
rechecked). With the correct temperature
rise across the heat exchanger (See TABLE I),
you may be assured of the proper velocity in
the tubes and long life and economical
operation from the water heater.
18 L o c h i n v a r
D E S I G N E R
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S G U I D E P O W E R
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F I N W A T E R H E A T E R
6 1 5 - 8 8 9 - 8 9 0 0
Lochinvar
(TABLE H) – INLET GAS PRESSURE REQUIREMENTS
NATURAL LP
PF0501 Max. Allowable 10.5" 13"
- 1300 Min. Allowable 4" 11"
PF1500 Max. Allowable 10.5" 13"
- 2000 Min. Allowable 4" 4"
(TABLE I) – REQUIRED TEMPERATURE RISE
MODEL TEMPERATURE
NUMBER RISE (°F)
PF0501 11
PF0751 17
PF1001 23
PF1300 30
PF1500 29
PF1700 33
PF2000 39
NOTE:
Care should be
taken to measure
temperature rise and
maintain proper water
velocity in the heat
exchanger.