Set Temperature Rise - Bryant G Series Installation & Operating Instructions Manual

TABLE 7—GAS RATE CU FT/HR
SIZE OF
SECONDS
TEST DIAL
FOR 1
1 2
REVOLUTION
cu ft cu ft
10 360 720
11 327 655
12 300 600
13 277 555
14 257 514
15 240 480
16 225 450
17 212 424
18 200 400
19 189 379
20 180 360
21 171 343
22 164 327
23 157 313
24 150 300
25 144 288
26 138 277
27 133 267
28 129 257
29 124 248
30 120 240
31 116 232
32 113 225
33 109 218
34 106 212
35 103 206
36 100 200
37 97 195
38 95 189
39 92 185
40 90 180
41 88 176
42 86 172
43 84 167
44 82 164
45 80 160
46 78 157
47 76 153
48 75 150
49 73 147
(3.) When correct input is obtained, replace regulator
seal cap. Main burner flame should be clear blue,
almost transparent. (See Fig. 13.)
INLET
PRESSURE TAP
→
Fig. 12—Redundant Automatic Gas Control Valve
d. High altitude—In the United States gas input on rating
plate is for altitudes up to 2000 ft. Ratings for altitudes
over 2000 ft must be 4 percent less for each 1000 ft
above sea level. To obtain the adjusted altitude rating,
adjust the manifold pressure (see item c) and replace the
main burner orifices as needed. Refer to National Fuel
Gas Code Appendix F, Table F-4 for proper orifice
sizing at high altitudes.
SIZE OF
SECONDS
TEST DIAL
FOR 1
5 1 2
REVOLUTION
cu ft cu ft cu ft
1800 50 72 144
1636 51 71 141
1500 52 69 138
1385 53 68 136
1286 54 67 133
1200 55 65 131
1125 56 64 129
1059 57 63 126
100 58 62 124
947 59 61 122
900 60 60 120
857 62 58 116
818 64 56 112
783 66 54 109
750 68
53 106
720 70 51 103
692 72 50 100
667 74 48 97
643 76 47 95
621 78 46 92
600 80 45 90
581 82 44 88
563 84 43 86
545 86 42 84
529 88 41 82
514 90 40 80
500 92 39 78
486 94 38 76
474 96 38 75
462 98 37 74
450 100 36 72
439 102 35 71
429 104 35 69
419 106 34 68
409 108 33 67
400
110 33 65
391
112 32 64
383
116 31 62
375
120 30 60
367
ON AND
OFF SWITCH
GAS
PRESSURE
REGULATOR
ADJUSTMENT
MANIFOLD
PRESSURE TAP
5
cu ft
360
355
346
340
333
327
321
316
310
305
300
290
281
273
265
257
250
243
237
231
225
e. Canadian installations only—The Canadian ratings are
220
approved for altitudes up to 2000 ft for natural and
214
propane gases. High-altitude ratings are from 2000 ft to
209
205
4500 ft above sea level. See Table 8 for nominal burner
200
orifice size. High-altitude rating includes a 10 percent
196
192 derate as required by Canadian standards.
188
184
180
178
GAS
173
170
Natural
167
Propane
164
161
155

2. Set temperature rise.

150
Furnace must operate within range of temperature rise
specified on the unit rating plate. Determine the air tem-
perature rise as follows.
a. Place duct thermometers in return and supply ducts as
near furnace as possible. Be sure thermometers do not
"see" heat exchangers so that radiant heat will not affect
thermometer readings. This is particularly important
with straight-run ducts.
b. When thermometer readings stabilize, subtract return-air
temperature from supply-air temperature to determine
temperature rise.
c. Adjust air temperature rise by adjusting blower speed.
Increase blower speed to reduce temperature rise. De-
crease blower speed to increase temperature rise.
WARNING: Disconnect the electrical power before
changing the speed tap. A failure to follow this warning
can cause personal injury.
d. To change blower motor speed selections for heating
mode, remove blower motor lead from control board
HEAT terminal. (See Fig. 11.) Select desired blower
A95618
motor speed lead from 1 of the other terminals and
relocate it to HEAT terminal. See Table 9 for lead color
identification. Reconnect original lead on SPARE termi-
nal.
CAUTION: Recheck temperature rise. It must be within
limits specified on unit rating plate. Recommended op-
eration is at midpoint of rise or above.
—13—
BURNER FLAME
MANIFOLD
Fig. 13—Burner Flame
TABLE 8—CANADIAN ORIFICE SIZE
SEA LEVEL
0—2000 FT
43
54
BURNER
A89020
HIGH ALTITUDE
2000—4500 FT
44
55