Gas Supply - Lochinvar POWER-FIN PF0501 Designer's Manual

Lochinvar
Locally purchased or fabricated sidewall vent
caps and air inlet caps must not be used. The
part numbers for the required sidewall vent
cap and air inlet cap kits are listed in TABLE
F. Each kit includes the vent cap and air inlet
cap for installation on an exterior sidewall for
a single appliance only.

GAS SUPPLY

The gas pressure regulator supplied is for
1.
low pressure service. If upstream pressure
exceeds 6 oz. (10.5" water column), an
intermediate gas pressure regulator, of the
lock up type, must be installed.
The gas line should be a separate line
2.
direct from meter, unless the existing
gas line is of sufficient capacity. Verify
pipe size with your gas supplier.
A trap (drip leg) should be provided in the
3.
inlet gas connection to the water heater.
A manual main gas shutoff valve is
4.
provided outside the jacket, upstream
of the main gas valve.
Nominal Iron
Pipe Size, Inches 10 20
3 /
369 256
4
1 697 477
1
1 /
1,400 974
4
1
1 /
2,150 1,500
2
2
4,100 2,820
1
2 / 6,460 4,460
2
3
11,200 7,900
23,500 16,100 13,100 11,100 10,000
4
Maximum capacity of pipe in thousands of Btu per hour for gas pressures of 14 Inches Water Column (0.5 PSIG) or less and a pressure
drop of 0.05 Inch Water Column (NAT GAS, 1025 Btu per Cubic Foot of Gas, based on 0.60 specific gravity gas).
L o c h i n v a r
D E S I G N E R
In Canada, derated10% from 2,000 -
5.
4,500 ft., over 4,500 ft. derate must be
in accordance with local authorities.
Consult factory for installations at
higher elevations.
High Altitude Applications
Atmospheric pressure decreases as the height
above sea level increases. At any altitude
above sea level, a cubic foot will contain less
gas than a cubic foot at sea level. Thus, the
heating value of a cubic foot of fuel gas will
decrease as height above sea level increases.
Specific gravity of a gas with respect to sea
level also decreases with altitude. These
changes in heating value and specific gravity
tend to offset each other. However, as
elevation above sea level is increased, there
is less oxygen per cubic foot of air. Therefore,
heat input rate should be reduced in an
appliance above 2000 feet; ratings should
be reduced at the rate of 4 percent for each
1000 feet above sea level.
(TABLE G) GAS SUPPLY PIPE SIZING
Length of Pipe In Straight Feet
30 40 50 60 70
205 174 155 141 128
384 328 292 267 246
789 677 595 543 502
1,210 1,020 923 830 769
2,260 1,950 1,720 1,560 1,440 1,330
3,610 3,100 2,720 2,460 2,310 2,100
6,400 5,400 4,870 4,410 4,000 3,800
9,000 8,300 7,690
' -
S G U I D E P O W E R F I N W A T E R H E A T E R
80 90 100 125 150
121 113 106 95 86
256 210 200 179 164
472 441 410 369 333
707 666 636 564 513
1,250 1,180 1,100 974
2,000 1,900 1,700 1,540
3,540 3,300 3,000 2,720
7,380 6,870 6,150 5,640
6 1 5 - 8 8 9 - 8 9 0 0
EXAMPLE OF
HIGH ALTITUDE
APPLICATIONS
For example, if a unit's
input is 1,000,000 Btu/hr
at sea level, the rated
input at 4000 feet of
elevation can be calculated
by derating input 4% per
1000 feet above sea level.
[Btu/hr Input]
[1.00 - (Elevation / 1000'
x 0.04)] = Btu/hr Input at
Specified Elevation
[1,000,000] [1.00 -
(4000' / 1000' x 0.04)]
= Btu/hr Input at 4000'
Elevation [1,000,000]
[0.84] = 840,000 Btu/hr
Input at 4000' Elevation
175 200
79 74
149 138
308 287
472 441
871 820
1,400 1,300
2,500 2,340
5,130 4,720
1 7