American Standard YCY024G1L Installation Operation & Maintenance page 15

INPUT CHECK AND ADJUSTMENT
1. Make sure all gas appliances are off except the furnace.
2. Clock the gas meter with the furnace operating (determine the
dial rating of the meter) for one revolution.
3. Match the "Sec" column in the gas flow (in cfh) Table 3 with the
time clocked.
4. Read the "Flow" column opposite the number of seconds
clocked.
5. Use the following factors if necessary.
For 1 Cu. Ft. Dial Gas Flow CFH =
Chart Flow Reading / 2
For 1/2 Cu Ft. Dial Gas Flow CFH =
Chart Flow Reading / 4
For 5 Cu. Ft. Dial Gas Flow CFH =
10X Chart Flow Reading / 4
6. Multiply the final figure by the heating value of the gas obtained
from the utility company and compare to the nameplate rating.
This must not exceed the nameplate rating.
7. Changes can be made by adjusting the manifold pressure.
a. Attach a manifold pressure gauge.
b. Remove the slot screw on top of the gas valve for 1st stage
manifold pressure adjustment. Remove slot screw on outlet
side for 2nd stage adjustment (See Figure 17).
c. Turn the adjustment nut in to increase the gas flow rate, and
out to decrease the gas flow rate using a 3/32" hex wrench.
HIGH ALTITUDE INSTALLATION
Unit nameplate ratings are based on equipment operation from sea
level to 2000 feet elevation above sea level. If the unit installation
is from 2000 - 4500 feet elevation, it will be necessary to change the
burner orifices to the noted sizes, (ref. National Fuel Gas Code, sec
8.1.2, Appendix F, Table F4).
G A S M A . N P R E
T Y P E i ( . n W C .
N A T U R A L 3 3 .
P R O P A N E 1 0 0 .
*
F A C
GAS PIPING INSTALLATION
S S O R F I C I E S Z I E O R F I
) . 0 - 2 0 0 0 t f 2 0 0 0
*
4 2
5 4
T O R Y S H P I P E D
GAS FLOW IN CUBIC FEET PER HOUR
Sec. Flow
8 900
9 800
10 720
11 655
12 600
13 555
14 514
15 480
16 450
17 424
18 400
19 379
20 360
21 343
22 327
23 313
24 300
25 288
26 277
27 267
28 257
u
C I E S Z I E
- 4 5 0 0 t f
4 3
5 5
TABLE 3
2 CUBIC FOOT DIAL
Sec. Flow Sec. Flow
29 248 50 144
30 240 51 141
31 232 52 138
32 225 53 136
33 218 54 133
34 212 55 131
35 206 56 129
36 200 57 126
37 195 58 124
38 189 59 122
39 185 60 120
40 180 62 116
41 176 64 112
42 172 66 109
43 167 68 106
44 164 70 103
45 160 72 100
46 157 74
47 153 76
48 150 78
49 147 80
1st Stage (Lo)
Adjustment
Switch Toggles
"ON" or "OFF"
Sec. Flow
82 88
84 86
86 84
88 82
90 80
92 78
94 76
96 75
98 73
100 72
104 69
108 67
112 64
116 62
120 60
124 58
128 56
97 132 54
95 136 53
92 140 51
90 144 50
2nd Stage (Hi)
Manifold
Pressure
Adjustment
Manifold
Pressure
Page 15