National Comfort Products Comfort Pack U Series, Руководство по установке

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Installation Guide | Comfort Pack with 80% Gas Heat
Clearances
Clearance to combustibles is defined as the minimum distance
from a heater to a surface or object that is necessary to ensure
that a surface temperature of 90°F above the surrounding
ambient temperature is not exceeded. Minimum clearance
to combustibles from all sides of this properly installed unit
is zero inches. Adequate clearances must be provided to
allow installation of the union and shutoff valve, as well as
accessibility to wiring and control compartments. If this unit
is installed in an attic or other insulated space, it must be kept
free and clear of insulating material. The area must be inspected
when the unit is installed or insulation is added. Some insulating
materials may be combustible. (See page 11 for other clearances)
Venting
The venting system is an integral part of the heater as shipped to
you. Do not modify or add to the vent system. The heat section
includes an exhaust blower. The blower draws the combustion
products out of the heat exchanger, mixes combustion products
with dilution air and forces the mixture to the outside. A chimney
is not required. No special provisions are required for supplying
air for combustion. Do not alter or extend the vent outlet. The
venting system is designed for proper operation under all
weather conditions and for winds up to 40 mph. (See page 11
for locating vent)
Gas Piping and Pressures
THIS HEATER IS EQUIPPED FOR A MAXIMUM
GAS SUPPLY PRESSURE OF 1/2 POUND, 8
OUNCES OR 14 INCHES WATER COLUMN.
SUPPLY PRESSURE HIGHER THAN 1/2
POUND REQUIRES INSTALLATION OF
AN ADDITIONAL LOCKUP-TYPE SERVICE
REGULATOR EXTERNAL TO THE UNIT.
!
WARNING
Gas piping external to the unit must include: a manual
shutoff valve with 1/8" NPT plugged tapping (for test
gauge connection), drip leg and ground union fitting.
If the supply air from the unit is ducted to space(s)
outside the space containing the unit, the return air
must be ducted from outside the space containing the
unit and sealed to the unit cabinet return air opening.
Pressure Testing Supply Piping
Test Pressures Above 1/2 PSI:
Disconnect the heat manual valve
from the gas supply line that is to be tested. Cap or plug the
supply line.
Test Pressures Below 1/2 PSI:
Before testing, close the manual
valve on the heater.
All piping must be in accordance with requirements outlined
in the National Fuel Gas Code ANSI/Z223,1a (latest edition) or
CAN/ CGA-B149.1 and B149.2. Gas supply piping installation
should conform with good practice and the local codes. Support
gas piping with pipe hangers, metal strapping or other suitable
material; do not rely on the heater to support the gas pipe.
CAPACITY OF PIPING
Cubic Feet Per hour Based on 0.3” w.c. Pressure Drop
Specific Gravity for Natural Gas - 0.6 (Natural Gas - 1000 BTU/Cubic Feet)
Specific Gravity for Propane Gas - 1.6 (Propane Gas - 2550 BTU/Cubic Feet
)
LENGTH
OF
PIPE
DIAMETER OF PIPE
1/2” 3/4” 1” 1 1/4” 1 1/2” 2”
NATURAL PROPANE NATURAL PROPANE NATURAL PROPANE NATURAL PROPANE NATURAL PROPANE NATURAL PROPANE
20’ 92 107 190 116 350 214 730 445 1100 671 2100 1281
30’ 73 45 152 93 285 174 590 360 890 543 1650 1007
40’ 63 38 130 79 245 149 500 305 760 464 1450 885
50’ 56 34 115 70 215 131 440 268 670 409 1270 775
60’ 50 31 105 64 195 119 400 244 610 372 1105 674
70’ 46 28 96 59 180 110 370 226 560 342 1050 641
80’ 43 26 90 55 170 104 350 214 530 323 990 604
90’ 40 24 84 51 160 98 320 195 490 299 930 567
100’ 38 23 79 48 150 92 305 186 460 281 870 531
125’ 34 21 72 44 130 79 275 168 410 250 780 476
150’ 31 19 64 39 120 73 250 153 380 232 710 433
160’ 28 17 59 36 110 67 225 137 350 214 650 397
170’ 26 16 55 34 100 61 210 128 320 195 610 372
Note:
When sizing lines, consider possibilities of future expansion
and increased requirements. Refer to National Fuel Gas Code for
additional information on line sizing.
T
he heater is orificed for operation with natural gas having a
heating value of 1000 (+/-50) BTUH per cubic feet or propane
gas with a heating valve of 2500 (+/-100) BTUH per cubic feet.
If the gas at the installation does not meet these specifications,
consult the factory for proper orificing.
Pipe joint compounds
(pipe dope) shall be resistant to the action of liquefied
petroleum gas or any other chemical constituents of the gas
being supplied.
Install a ground joint union and manual shut off valve upstream of
the unit control system, as shown in Figure 2. The 1/8” plugged
tapping in the shut off valve provides connection for a supply
line pressure test gauge**. The National Fuel Gas Code requires
the installation of a trap with a minimum 3" drip leg. Local codes
may require a minimum drip leg longer than 3" (typically 6"). Gas
connection is 1/2". Leak-test all connections by brushing on a
leak-detecting solution.