Check Safety Controls - Bryant 355BAV Installation, Start-Up, And Operating Instructions Manual

SECONDS
FOR 1
REVOLUTION
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
Set Thermostat Heat Anticipator
When using a non- -electronic thermostat, the thermostat heat
anticipator must be set to match the amp draw of components in
the R- -W/W1 circuit. Accurate amp draw measurements can be
obtained only at the thermostat subbase terminals R and W.
The thermostat and anticipator should NOT be in the circuit while
measuring current. If thermostat has no subbase, the thermostat
must be disconnected from R and W/W1 wires during current
measurement.
Fig. 54 illustrates an easy method of obtaining thermostat amp
draw measurements. The amp reading should be taken after blower
motor has started and furnace is operating in low- -heat.
1. To operate furnace in low- -heat, turn setup switch SW1- -2 to
ON position (See Fig. 33) and connect ammeter leads across
thermostat subbase R- -W.
2. See thermostat manufacturer's instructions for adjusting the
heat anticipator and for varying heating cycle length.
NOTE: When using an electronic thermostat, set cycle rate for 3
cycles per hr.
3. Return setup switch SW1- -2 to OFF position and replace
thermostat on subbase.

Check Safety Controls

This section covers the safety controls that must be checked before
the installation is complete. The flame sensor, gas valve, and
pressure switches were all checked in the Start- -up procedure
section as part of normal operation.
Table 13 – Gas Rate Cu Ft/Hr
SIZE OF TEST DIAL
1 2 5
cu ft cu ft cu ft
360 720 1800
327 655 1636
300 600 1500
277 555 1385
257 514 1286
240 480 1200
225 450 1125
212 424 1059
200 400 1000
189 379 947
180 360 900
171 343 857
164 327 818
157 313 783
150 300 750
144 288 720
138 277 692
133 267 667
129 257 643
124 248 621
120 240 600
116 232 581
113 225 563
109 218 545
106 212 529
103 206 514
100 200 500
97 195 486
95 189 474
92 185 462
90 180 450
88 176 439
86 172 429
84 167 419
82 164 409
80 160 400
78 157 391
76 153 383
75 150 375
73 147 367
SECONDS
FOR 1
REVOLUTION
50
51
52
53
54
55
56
57
58
59
60
62
64
66
68
70
72
74
76
78
80
82
84
86
88
90
92
94
96
98
100
102
104
106
108
110
112
116
120
Check Primary Limit Control
This control shuts off the gas control system and energizes the
air- -circulating blower motor if furnace overheats.
1. The recommended method of checking this limit control is
to gradually block off return air after furnace has been oper-
ating for a period of at least 5 minutes.
2. As soon as limit control has shut off burners, a status code
33 will appear on furnace control.
3. The return- -air opening should be unblocked to permit nor-
mal air circulation.
By using this method to check the limit control, it can be
established that the limit is functioning properly and the furnace
will operate safely if there is a restricted return- -air duct or motor
failure. If the limit control does not function during this test, the
cause must be determined and corrected.
Check Pressure Switches
This control proves operation of the draft inducer. Check switch
operation as follows:
1. Turn off 115- -v power to furnace.
2. Remove control access door and disconnect inducer motor
12- -pin wire harness at inducer motor.
3. Turn on 115- -v power to furnace.
49
SIZE OF TEST DIAL
1 2 5
cu ft cu ft cu ft
72 144 360
71 141 355
69 138 346
68 136 340
67 133 333
65 131 327
64 129 321
63 126 316
62 124 310
61 122 305
60 120 300
58 116 290
56 112 281
54 109 273
53 106 265
51 103 257
50 100 250
48 97 243
47 95 237
46 92 231
45 90 225
44 88 220
43 86 214
42 84 209
41 82 205
40 80 200
39 78 196
38 76 192
38 75 188
37 74 184
36 72 180
35 71 178
35 69 173
34 68 170
33 67 167
33 65 164
32 64 161
31 62 155
30 60 150