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WARNING:
Open flame can cause gas to ignite and result in
property damage, severe injury, or loss of life.
NOTE
: The LT Series appliance and all other gas
appliances sharing the gas supply line must be firing at
maximum capacity to properly measure the inlet supply
pressure. The pressure can be measured at the supply
pressure port on the gas valve. Low gas pressure could
be an indication of an undersized gas meter, undersized
gas supply lines and/or an obstructed gas supply line.
SCHED 40 METAL PIPE CAPACITY FOR 1.50 SPECIFIC GRAVITY
UNDILUTED PROPANE
NOMINAL PIPE SIZE
@
11" W.C. INLET AND 0.5" W.C. PRESSURE DROP
SIZE
1/2"
3/4"
1"
LENGTH
MAXIMUM CAPACITY IN THOUSANDS OF BTU PER HOUR
20
200
418
787
40
-
287
541
60
-
231
434
80
-
197
372
100
-
175
330
NOTES:
1. Follow all local and national propane gas codes for line sizing and
equipment requirements. 2. Verify that inlet gas pressure remains between
4 and 13 inches of water column before and during operation.
Source: ANSI Z223.1-80 National Fuel Gas Code.
Table 7. Nominal Pipe Size, Propane
SCH 40 METAL PIPE CAPACITY FOR 0.60 SPECIFIC GRAVITY NATURAL GAS
NOMINAL PIPE SIZE
@
0.30" W.C. PRESSURE DROP
SIZE
1/2"
3/4"
1"
FT CUBIC FEET OF GAS PER HOUR
20
92
190
350
40
-
130
245
60
-
105
195
80
-
90
170
100
Table 8. Nominal Pipe Size, Natural Gas
4.9 Gas Supply and Piping
Gas piping should be supported by suitable hangers or
floor stands, not the appliance.
Review the following instructions before proceeding with
the installation.
1. Verify that the appliance is fitted for the proper type
of gas by checking the rating plate. LT Series water
heaters will function properly at elevations up to
10,000 feet (3050 m). Refer to Section 4.12 for High
Altitude Settings.
2. Refer to Table 7, Table 8, and Table 9 for sizing
piping.
3. For minimum and maximum gas supply pressures,
see Table 10.
4. Run gas supply line in accordance with all applicable
codes.
5. Locate and install manual shutoff valves in
accordance with state and local requirements.
6. A sediment trap must be provided upstream of the
gas controls.
7. All threaded joints should be coated with piping
compound resistant to action of liquefied petroleum
gas.
8. The appliance and its individual shutoff valve must be
disconnected from the gas supply piping during any
pressure testing of that system at test pressures in
excess of 1/2 PSIG (3.45kPa).
9. The unit must be isolated from the gas supply system
by closing its individual manual shutoff valve during
any pressure testing of the gas supply piping system
at test pressures equal to or less than 1/2 PSIG
(3.45kPa).
10. The appliance and its gas connection must be leak
tested before placing it in operation.
11. Purge all air from gas lines.
12. Note if using 1/2" Gas line a maximum of 24
equivalent feet is allowed.
EQUIVALENT LENGTHS OF STRAIGHT PIPE FOR TYPICAL SCH 40 FITTINGS
NOMINAL PIPE SIZE
FITTING
1/2"
3/4"
1"
LINEAR FEET
90° ELBOW
3.6
4.4
5.2
TEE
4.2
5.3
6.6
Table 9. Equivalent Pipe Lengths
Summary of Contents for LT Series
Page 42: ...Page 42 4 20 Wiring Diagram...
Page 43: ...Page 43 4 21 Ladder Diagram...
