F97CMN and G97CMN: Installation, Start-up, Operating and Service and Maintenance Instructions
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
54
3. Jumper R to W/W1 and W2. Run furnace for 3 minutes in
maximum heat operation.
4. Measure time (in sec) for gas meter to complete one revolution and
note reading. The 2 or 5 cubic feet dial provides a more accurate
measurement of gas flow.
5. Refer to
for cubic ft. of gas per hr. Multiply gas rate cu
ft./hr by heating value (BTUh/cu ft.) to obtain input rate.
6. If clocked rate does not match required input from Step 5, increase
manifold pressure to increase input or decrease manifold pressure
to decrease input. Repeat steps 3 through 5 until correct maximum
heat input is achieved. See
NOTE:
Setup switches SW1-2 must be ON and SW4-2 must be OFF.
This keeps furnace locked in minimum heat operation when R to W/W1
is energized. Repeat items 3 through 6 for minimum heat operation until
minimum heat input is achieved.
7. Remove jumpers across thermostat connections to terminate the
call for heat. Wait until the blower off delay is completed then reset
115-v power to furnace.
8. Restore furnace to normal operating condition.
A11461
Fig. 63 – Burner Flame
9. Remove jumpers across thermostat connections to terminate the
call for heat. Wait until the blower off delay is completed.
10. Disconnect 115 VAC power to furnace.
11. Turn gas valve ON/OFF switch to OFF.
12. Remove water column manometer or similar device from manifold
pressure tap.
13. Tighten set screw on manifold tower pressure tap with 3/32-in hex
wrench, or if 1/8-in. NPT plug was removed, apply pipe dope
sparingly to end of plug and reinstall in the gas valve.
14. Turn gas valve ON/OFF switch to ON.
15. Move setup SW1-2 on furnace control to position required for
attached thermostat (OFF for single-stage thermostats, ON for
two-stage thermostats).
16. Check for gas leaks and verify furnace operation.
.
Adjust Temperature Rise
NOTE:
Blower door must be installed when taking temperature rise
reading. Leaving blower door off will result in incorrect temperature
measurements,
due to possible changes in duct static pressure and
airflow.
When setup switch SW1-4 is ON, operation will be near the high end of
the rise range for improved comfort.
Furnace must operate within ranges of temperature rise specified on the
furnace rating plate. Determine air temperature rise as follows:
WARNING
!
FIRE HAZARD
Failure to follow this warning could result in personal injury, death,
and/or property damage.
Manifold pressure tap set screw must be tightened or
⅛
-in. NPT pipe
plug must be installed to prevent gas leaks.
Table 17 – Gas Rate (CU ft./hr)
SECONDS
FOR 1 REV
SIZE OF TEST DIAL
SECONDS
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
50
72
144 360
11
327
655 1636
51
71
141 355
12
300
600 1500
52
69
138 346
13
277
555 1385
53
68
136 340
14
257
514 1286
54
67
133 333
Burner Flame
Burner
Manifold
15
240
480 1200
55
65
131 327
16
225
450 1125
56
64
129 321
17
212
424 1059
57
63
126 316
18
200
400 1000
58
62
124 310
19
189
379
947
59
61
122 305
20
180
360
900
60
60
120 300
21
171
343
857
62
58
116 290
22
164
327
818
64
56
112 281
23
157
313
783
66
54
109 273
24
150
300
750
68
53
106 265
25
144
288
720
70
51
103 257
26
138
277
692
72
50
100 250
27
133
267
667
74
48
97
243
28
129
257
643
76
47
95
237
29
124
248
621
78
46
92
231
30
120
240
600
80
45
90
225
31
116
232
581
82
44
88
220
32
113
225
563
84
43
86
214
33
109
218
545
86
42
84
209
34
106
212
529
88
41
82
205
35
103
206
514
90
40
80
200
36
100
200
500
92
39
78
196
37
97
195
486
94
38
76
192
38
95
189
474
96
38
75
188
39
92
185
462
98
37
74
184
40
90
180
450
100
36
72
180
41
88
176
439
102
35
71
178
42
86
172
429
104
35
69
173
43
84
167
419
106
34
68
170
44
82
164
409
108
33
67
167
45
80
160
400
110
33
65
164
46
78
157
391
112
32
64
161
47
76
153
383
116
31
62
155
48
75
150
375
120
30
60
150
49
73
147
367
CAUTION
!
FURNACE DAMAGE HAZARD
Failure to follow this caution may result in:
S
Overheating the heat exchangers or condensing flue gases in heat
exchanger areas not designed for condensate.
S
Shortened furnace life
S
Component damage.
Temperature rise must be within limits specified on furnace rating plate.
Recommended operation is at midpoint of rise range or slightly above.
Table 17 – Gas Rate (CU ft./hr) (Continued)
