Carrier PG80MSU, Installation, Start-Up, Operating And Service And Maintenance Instructions

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PG80MSU: 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.
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Table 14 – Altitude Derate Multiplier for U.S.A
.
Furnace gas input rate on rating plate is for installations at altitudes up to
2,000 ft. (610 M). Furnace input rate must be within +/-2 percent of
furnace rating plate input.
2. Determine the correct outlet gas pressure adjustment.
a. Obtain average yearly gas heat value (at installed altitude) from
local gas supplier.
b. Obtain average yearly gas specific gravity from local gas
supplier.
c. Find closest natural gas heat value and specific gravity in
Table 16 through Table 19 .
d. Follow heat value and specific gravity lines to point of
intersection to find outlet pressure setting for proper operation.
3. Check Inlet Gas Pressure
The inlet gas pressure must be checked with the furnace operating. This
is necessary to make sure the inlet gas pressure does not fall below the
minimum pressure of 4.5 in. w.c.
a. Make sure the gas supply is turned off to the furnace and at the
electric switch on the gas valve
b. Loosen set screw on inlet tower pressure tap no more than one
full turn with a 3/32−in. hex wrench or remove the 1/8−in. NPT
plug from the inlet pressure tap on the gas valve.
c. Connect a manometer to the inlet pressure tap on gas valve.
d. Turn on furnace power supply.
e. Turn gas supply manual shutoff valve to ON position.
f. Turn furnace gas valve switch to ON position.
g. Jumper R and W thermostat connections at the furnace control
board.
h. When main burners ignite, confirm inlet gas pressure is between
4.5 in. w.c. (1125 Pa) and 13.6 in. w.c. (3388 Pa).
i. Remove jumper across thermostat connections to terminate call
for heat. Wait until the blower off delay is completed.
j. Turn furnace gas valve electric switch to OFF position.
k. Turn gas supply manual shutoff valve to OFF position.
l. Turn off furnace power supply.
m.Remove manometer from the inlet pressure tap of the gas valve.
n. Tighten set screw on inlet 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
4. Adjust gas valve outlet pressure determined in Step 2 to obtain
correct input rate.
a. Turn gas valve ON/OFF switch to OFF.
b. Loosen set screw on outlet tower pressure tap no more than one
full turn with a 3/32 in. hex wrench, see Fig. 21 .
c. Connect a water column manometer or similar device to pressure
tap on the gas valve.
d. Turn gas valve ON/OFF switch to ON.
e. Manually close blower door switch.
f. Set thermostat to call for heat.
g. Remove regulator seal cap and turn regulator adjusting screw
counterclockwise (out) to decrease input rate of clockwise (in) to
increase input rate.
h. Install regulator seal cap.
i. Leave manometer or similar device connected and proceed to
next step.
NOTE: If orifice hole appears damaged or it is suspected to have been
redrilled, check orifice hole with a numbered drill bit of correct size.
Never redrill an orifice. A burr-free and properly sized orifice hole is
essential for proper flame characteristics.
Table 15 – Gas Rate (Cu Ft./Hr.)
5. Verify natural gas input rate by clocking meter.
NOTE: Gas valve regulator adjustment cap must be in place for proper
input to be clocked.
a. Turn off all other gas appliances and pilots served by the meter.
b. Run furnace for 3 minutes in heating operation.
c. Measure time (in seconds) for gas meter to complete 1 revolution
and note reading. The 2 or 5 cubic feet dial provides a more
accurate measurement of gas flow.
d. Refer to Table 15 for cubic ft. of gas per hr.
ALTITUDE
(FT. / M)
PERCENT
OF
DERATE
DERATE
MULTIPLIER
FACTOR
*
*. Derate multiplier factors are based on midpoint altitude for altitude range
0–2000 (0-610) 0 1.00
2001–3000 (610-914)
4-6 0.95
3001–4000 (914-1219) 6-8 0.93
4001–5000 (1219-1524)
8-10 0.91
5001–5400 (1525-1646) 10-11 0.90
WARNING
!
FIRE HAZARD
Failure to follow this warning could result in personal injury, death,
and/or property damage.
Inlet pressure tap set screw must be tightened and 1/8-in. NPT pipe
plug must be installed to prevent gas leaks.
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
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