Carrier N92ESN Installation, Start-Up, Operating And Service And Maintenance Instructions page 50

N92ESN: Installation, Start-up, Operating and Service and Maintenance Instructions
b. Turn gas valve ON/OFF switch to OFF.
c. Loosen set screw on manifold tower pressure tap no more than
one full turn with a 3/32-in. hex wrench, or remove the 1/8 inch
NPT plug from the manifold pressure tap on the gas valve.
d. Connect a water column manometer or similar device to
manifold pressure tap.
e. Turn gas valve ON/OFF switch to ON.
f. Manually close blower door switch.
g. Jumper R and W thermostat connections on control to start
furnace. See Fig. 36.
h. Remove regulator adjustment cap from gas valve pressure
regulator and turn adjusting screw (3/16 or smaller flat-tipped
screwdriver) counterclockwise (out) to decrease input rate or
clockwise (in) to increase input rate. See
!
DO NOT set manifold pressure less than 2.8-in. w.c. (697 Pa) or more
than 3.8 in. w.c. (947 Pa) for natural gas. If required manifold pressure
is outside this range, change main burner orifices to obtain manifold
pressure in this range.
i. When correct input is obtained, replace cap that conceals gas
valve regulator adjustment screws. Main burner flame should be
clear blue, almost transparent See
SINGLE-STAGE
ON/OFF Switch
1/2" NPT Inlet
1/8" NPT Inlet
Pressure Tap
Representative drawing only, some models may vary in appearance.
Fig. 61 – Gas Valve without Tower Pressure Ports
MANIFOLD PRESSURE TAP SET SCREW:
3/32" HEX HEAD ACCEPTS
INLET PRESSURE TAP
SET SCREW: 3/32" HEX HEAD
ACCEPTS 5/16" HOSE
CONNECTION
1/2" NPT
INLET
ON/OFF SWITCH
Representative drawing only, some models may vary in appearance.
Fig. 62 – Gas Valve with Tower Pressure Ports
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
Fig. 61.
NOTICE
Fig. 63.
Regulator Seal Cap
Regulator Adjustment
Regulator Seal Cap under Cap
1/2" NPT Outlet
1/8" NPT Manifold
Pressure Tap
REGULATOR SEAL CAP
(REGULAR ADJ. UNDER CAP)
5/16" HOSE CONNECTION
OUTP
1/2" NPT
OUTLET
Manifold
j. Remove jumper R to W.
2. Verify natural gas input rate by clocking meter.
NOTE: Contact your HVAC distributor or gas supplier for metric gas
meter Tables, if required.
a. Turn off all other gas appliances and pilots served by the meter.
b. Jumper R to W.
c. Run furnace for 3 minutes.
d. 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.
e. Refer to Table 18
Table 18 – Gas Rate (CU ft./hr)
SEC. SIZE OF TEST DIAL
FOR 1
1 Cu
REV.
Ft.
10 360
11 327
12 300
13 277
14 257
15 240
16 225
17 212
18 200
19 189
20 180
21 171
22 164
23 157
24 150
25 144
26 138
27 133
28 129
A11153
29 124
30 120
31 116
32 113
33 109
34 106
35 103
36 100
37 97
38 95
39 92
40 90
41 88
42 86
43 84
44 82
A170118
45 80
46 78
47 76
48 75
49 73
f. Multiply gas rate cu ft./hr by heating value (BTUh/cu ft.) to
obtain input rate.
50
Burner Flame
Burner
Fig. 63 – Burner Flame
for cubic ft. of gas per hr.
SEC. SIZE OF TEST DIAL
FOR 1
2 Cu 5 Cu 1 Cu
REV.
Ft. Ft. Ft.
720 1800 50 72
655 1636 51 71
600 1500 52 69
555 1385 53 68
514 1286 54 67
480 1200 55 65
450 1125 56 64
424 1059 57 63
400 1000 58 62
379 947 59 61
360 900 60 60
343 857 62 58
327 818 64 56
313 783 66 54
300 750 68 53
288 720 70 51
277 692 72 50
267 667 74 48
257 643 76 47
248 621 78 46
240 600 80 45
232 581 82 44
225 563 84 43
218 545 86 42
212 529 88 41
206 514 90 40
200 500 92 39
195 486 94 38
189 474 96 38
185 462 98 37
180 450 100 36
176 439 102 35
172 429 104 35
167 419 106 34
164 409 108 33
160 400 110 33
157 391 112 32
153 383 116 31
150 375 120 30
147 367
A11461
2 Cu 5 Cu
Ft. Ft.
144 360
141 355
138 346
136 340
133 333
131 327
129 321
126 316
124 310
122 305
120 300
116 290
112 281
109 273
106 265
103 257
100 250
97 243
95 237
92 231
90 225
88 220
86 214
84 209
82 205
80 200
78 196
76 192
75 188
74 184
72 180
71 178
69 173
68 170
67 167
65 164
64 161
62 155
60 150