Bryant 935SA, Manual

Page: 47 / 60

935SA: Installation, Start-up, Operating and Service Maintenance Instructions
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
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A96316
Fig. 62 – Amp. Draw Check With Ammeter
b. Electronic thermostat: Set cycle rate for 4 cycles per hr.
9. Adjust Cooling Airflow. The cooling airflow can be set from the
remaining blower speed taps. Refer to the Air Delivery Tables in
these instructions.
10. Adjust blower off delay. The blower off delay has four (4)
adjustable settings from 90 seconds to 180 seconds. The blower off
delay jumpers are located on the furnace control board - see wiring
diagram (see Fig. 68 ). Position A-90 seconds, B-120 seconds,
C-150 seconds, D-180 seconds.
To change the blower off delay setting, move the jumper from one
set of pins on the control to the pins used for the selected blower off
delay. Factory off delay setting is 120 seconds.
11. Cooling On Delay is fixed at 2 seconds for either jumper selection.
Check Safety Controls
1. Check Main Limit Switch(es)
This control shuts off combustion control system and energizes
air-circulating blower motor, if furnace overheats. By using this
method to check limit control, it can be established that limit is
functioning properly and will operate if there is a restricted duct
system or motor failure. If limit control does not function during
this test, cause must be determined and corrected.
a. Run furnace for at least 5 minutes.
b. Gradually block off return air with a piece of cardboard or sheet
metal until the limit trips.
c. Unblock return air to permit normal circulation for 5 minutes.
d. Main limit circuit open causes 3 hour lock out.
e. Reset unit power to clear limit fault lockout.
Checklist
1. Put away tools and instruments. Clean up debris.
2. Verify that the Blower/Heat Off Delay jumpers are set as desired.
(see Fig. 41 and Fig. 68 ).
3. Verify that there are no unsealed openings in the blower shelf or
casing.
4. Verify that the blower (lower door in upflow position) and control
(“Main” or upper door in upflow position) doors are properly
installed.
5. Verify that the Status LED glows. If not, check that the power
supply is energized and that the blower door is secure. Interpret
diagnostic codes (see Fig. 63 ).
6. Cycle test furnace with room thermostat to be sure that it operates
properly with the room thermostat. Check all modes including
Heat, Cool and Fan.
7. Check operation of accessories per manufacturer’s instructions.
8. Review Owner’s Manual with owner.
9. Attach entire literature packet to furnace.
R Y W G
10 TURNS
THERMOSTAT SUBBASE
TERMINALS WITH
THERMOSTAT REMOVED
(ANITICIPATOR, CLOCK, ETC.,
MUST BE OUT OF CIRCUIT.)
HOOK-AROUND
AMMETER
EXAMPLE:
5.0 AMPS ON AMMETER
10 TURNS AROUND JAWS
=
0.5 AMPS FOR THERMOSTAT
ANTICIPATOR SETTING
FROM UNIT 24-V
CONTROL TERMINALS
Table 21 – Gas Rate (CU ft./hr)
SEC
FOR 1
REV
SIZE OF TEST DIAL
SEC
FOR 1
REV
SIZE OF TEST DIAL
1 Cu
Ft.
2 Cu
Ft.
5 Cu
Ft.
1 Cu
Ft.
2 Cu
Ft.
5 Cu
Ft.
10 360 720 1800 55 65 131 327
11 327 655 1636 56 64 129 321
12 300 600 1500 57 63 126 316
13 277 555 1385 58 62 124 310
14 257 514 1286 59 61 122 305
15 240 480 1200 60 60 120 300
16 225 450 1125 62 58 116 290
17 212 424 1059 64 56 112 281
18 200 400 1000 66 54 109 273
19 189 379 947 68 53 106 265
20 180 360 900 70 51 103 257
21 171 343 857 72 50 100 250
22 164 327 818 74 48 97 243
23 157 313 783 76 47 95 237
24 150 300 750 78 46 92 231
25 144 288 720 80 45 90 225
26 138 277 692 82 44 88 220
27 133 267 667 84 43 86 214
28 129 257 643 86 42 84 209
29 124 248 621 88 41 82 205
30 120 240 600 90 40 80 200
31 116 232 581 92 39 78 196
32 113 225 563 94 38 76 192
33 109 218 545 96 38 75 188
34 106 212 529 98 37 74 184
35 103 206 514 100 36 72 180
36 100 200 500 102 35 71 178
37 97 195 486 104 35 69 173
38 95 189 474 106 34 68 170
39 92 185 462 108 33 67 167
40 90 180 450 110 33 65 164
41 88 176 439 112 32 64 161
42 86 172 429 116 31 62 155
43 84 167 419 120 30 60 150
44 82 164 409 124 29 58 145
45 80 160 400 129 28 56 140
46 78 157 391 133 27 54 135
47 76 153 383 138 26 52 130
48 75 150 375 144 25 50 125
49 73 147 367 150 24 48 120
50 72 144 360 157 23 46 115
51 71 141 355 164 22 44 110
52 69 138 346 171 21 42 105
53 68 136 340 180 20 40 100
54 67 133 333