Rheem H2AC, Руководство по установке

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Maximum capacity of pipe in thousands of BTU per hour of undiluted liquefied petroleum
gases (at 11 inches water column inlet pressure).
(Based on a Pressure Drop of 0.5 Inch Water Column)
TABLE 2
LP GAS PIPE CAPACITY TABLE (CU. FT./HR.)
Nominal
Iron Pipe
Size, Inches
10 20 30 40 50 60 70 80 90 100 125 150
275 189 152 129 114 103 96 89 83 78 69 63
567 393 315 267 237 217 196 182 173 162 146 132
1,071 732 590 504 448 409 378 346 322 307 275 252
2,205 1,496 1,212 1,039 913 834 771 724 677 630 567 511
3,307 2,299 1,858 1,559 1,417 1,275 1,181 1,086 1,023 976 866 787
6,221 4,331 3,465 2,992 2,646 2,394 2,205 2,047 1,921 1,811 1,606 1,496
1/2
3/4
1
1-1/4
1-1/2
2
Length of Pipe, Feet
Example (LP): Input BTU requirement of unit, 150,000
Equivalent length of pipe, 60 ft. = 3/4 ” IPS required.
FIGURE 10B
HONEYWELL VR8305Q4120 TWO STAGE GAS VALVE
C. ADJUSTING OR CHECKING FURNACE INPUT
– Natural Gas Line Pressure 5” - 10.5” W.C.
– LP Gas Line Pressure 11” - 13” W.C.
– Natural Gas Manifold Pressure 3.5” W.C
– LP Gas Manifold Pressure - 10” W.C.
Supply and manifold pressure taps are located on the gas valve body 1/8” N.P.T. and
on the manifold. See Figure 10B.
Use a properly calibrated manometer gauge for accurate gas pressure readings.
Only small variations in the gas flow should be made by means of the pressure regula-
tor adjustment. Furnaces functioning on LP gas must be set by means of the tank or
branch supply regulators. The furnace manifold pressure should be set at 10” W.C. at
the gas control valve.
To adjust the pressure regulator, remove the regulator vent cover and turn the adjust-
ment screw clockwise to increase pressure or counterclockwise to decrease pressure.
See Figure 10B. Then replace the regulator vent cover securely.
Any necessary major changes in the gas flow rate should be made by changing the size
of the burner orifices. To change orifice spuds, shut off the manual main gas valve and
remove the gas manifold.
For elevations up to 2,000 feet, rating plate input ratings apply. For high altitudes (eleva-
tions over 2,000 ft.), see conversion kit index 92-21519-XX for derating and orifice spud
sizes.
Check of input is important to prevent over-firing of the furnace beyond its
design-rated input. NEVER SET INPUT ABOVE THAT SHOWN ON THE RATING
PLATE. Use the following table or formula to determine input rate.
INLET PRESSURE TAP - 1/8 NPT
GAS INLET - 3/4“ [25.4] FNPT
ORDERING
SPECIFICATION
LABEL
OUTLET PRESSURE
TAP - 1/8 NPT
LOW STAGE ADJUSTMENT
UNDER VENT CAP
WHEN INSTALLING THE GAS INLET PIPE, A BACKUP
WRENCH MUST BE USED ON THE GAS VALVE TO
AVOID DAMAGE.
HIGH STAGE ADJUSTMENT
UNDER VENT CAP
GROUND TERMINAL
2-STAGE
OPERATOR