Field Controls PVG-100, Руководство пользователя

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POWER VENTER SIZING
In order to choose the correct size power venter for a particular installation, the total input fi ring rate and
total equivalent length of vent pipe to be used must be known. Refer to Table 2 to determine the maximum
allowable equivalent feet of pipe for each model used with the pipe diameters shown. When venting
multiple appliances, add the input of each appliance to determine the total input. Always choose a power
venter that is capable of handling more than the system requires. The choke plate can be adjusted to
compensate for the diff erence.
MAXIMUM EQUIVALENT HORIZONTAL PIPE LENGTH (FEET)
BTU/HR INPUT
VENTER MODEL NUMBER AND VENT PIPE DIAMETER
PVG-100 PVG-300 PVG-600
3" 4" 4" 5" 6" 5" 6" 8"
25,000 270 455 -- -- -- -- -- --
55,000 100 169 -- -- -- -- -- --
70,000 -- 144 -- -- -- -- -- --
100,000 -- 100 305 -- -- -- -- --
145,000 -- -- 145 247 334 413 -- --
220,000 -- -- 64 100 147 181 -- --
310,000 -- -- -- 54 74 91 146 216
400,000 -- -- -- -- -- 54 87 134
520,000 -- -- -- -- -- -- 52 86
610,000 -- -- -- -- -- -- -- 66
Table 2
PROCEDURE FOR CALCULATING TOTAL EQUIVALENT PIPE LENGTH IN FEET
1. Calculate the total equivalent feet for each type of fi tting used in the venting system from the following chart.
2. Calculate the total amount of feet for the straight lengths of vent pipe.
3. Add the equivalent feet for the fi ttings with the total amount of feet of straight lengths.
Table 3
*Reducer or increaser ratio (d/D) small diameter divided by the larger diameter. (See Figure 3)
Example: 4" to 8" reducer, the reducer ratio is d/D = 4 ⁄
8
= 1 ⁄
2
. To estimate the
equivalent foot length for the fi tting, use the smaller pipe diameter for the equivalent
length fi gure. Example: 4" to 8" reducer; the reducer ratio is
1 ⁄
2
and the smaller pipe
diameter is 4". So, from the chart, the equivalent feet would be 7 feet.
Example: System Pipe Size = 4"
Step 1 2 – 90° Elbows (4") = 14 Ft.
Step 2 10 - 2 Ft. Lengths of 4" Pipe = 20 Ft.
Step 3 Total Equivalent Feet = 14 Ft. + 20 Ft. = 34 Ft.
Figure 3
EQUIVALENT LENGTH (FEET) OF VENT PIPE FOR VENT PIPE FITTINGS
VENT PIPE FITTINGS
VENT PIPE DIAMETER
3" 4" 5" 6" 7" 8" 9" 10"
TEE 19 25 31 38 44 50 56 63
90° ELBOW 5 7 9 11 12 14 16 18
45° ELBOW 3 4 4 5 6 7 8 9
REDUCER
(d/D)*
1
⁄
4
8 11 14 17 19 22 25 28
1
⁄
2
5 7 8 10 12 13 15 17
3
⁄
4
2 3 3 4 4 5 6 6
P/N 46246300 Rev M 04/20