Carrier 58MXA Installation, Start-Up, And Operating Instructions Manual page 48

Table 12—Gas Rate (cu ft/hr)
SIZE OF TEST DIAL
SECONDS
FOR 1
1 2
REVOLUTION
Cu Ft Cu Ft
10 360 720
11 327 655
12 300 600
13 277 555
14 257 514
15 240 480
16 225 450
17 212 424
18 200 400
19 189 379
20 180 360
21 171 343
22 164 327
23 157 313
24 150 300
25 144 288
26 138 277
27 133 267
28 129 257
29 124 248
30 120 240
31 116 232
32 113 225
33 109 218
34 106 212
35 103 206
36 100 200
37 97 195
38 95 189
39 92 185
40 90 180
41 88 176
42 86 172
43 84 167
44 82 164
45 80 160
46 78 157
47 76 153
48 75 150
49 73 147
13 for lead color identification. Reconnect original lead on
SPARE terminal.
Follow this same procedure for proper selection of COOL
speed selection.
ADJUST BLOWER OFF DELAY (HEAT MODE)
The blower off delay has 4 adjustable settings from 90 sec to 180
sec. (See Table 14.) The blower off delay jumpers are located on
the furnace control (See Fig. 31). To change the blower off delay
setting, move the jumper from one set of pins on the control to the
pins used for the desired blower off delay. Factory blower off
delay setting is 120 sec.
→
Table 14—Blower Off Delay Jumper Positions
PINS 1 AND 2
Time (in sec) 90
SIZE OF TEST DIAL
SECONDS
FOR 1
5 1 2
REVOLUTION
Cu Ft Cu Ft Cu Ft
1800 50 72 144
1636 51 71 141
1500 52 69 138
1385 53 68 136
1286 54 67 133
1200 55 65 131
1125 56 64 129
1059 57 63 126
1000 58 62 124
947 59 61 122
900 60 60 120
857 62 58 116
818 64 56 112
783 66 54 109
750 68 53 106
720 70 51 103
692 72 50 100
667 74 48 97
643 76 47 95
621 78 46 92
600 80 45 90
581 82 44 88
563 84 43 86
545 86 42 84
529 88 41 82
514 90 40 80
500 92 39 78
486 94 38 76
474 96 38 75
462 98 37 74
450 100 36 72
439 102 35 71
429 104 35 69
419 106 34 68
409 108 33 67
400 110 33 65
391 112 32 64
383 116 31 62
375 120 30 60
367 124 29 58
2 AND 3 3 AND 4 4 AND 5
120 150 180
Table 13—Speed Selector
COLOR
5
Cu Ft
Black
360
355 Yellow (When Present)
346
Blue
340
Red
333
White
327
321
SET THERMOSTAT HEAT ANTICIPATOR
316
When using a nonelectronic thermostat, the thermostat heat
310
anticipator must be set to match the amp draw of the electrical
305
300 components in R-W circuit. Accurate amp draw readings can be
290 obtained at thermostat subbase terminals R and W. Fig. 60
281 illustrates the easy method of obtaining actual amp draw. The amp
273
reading should be taken after blower motor has started and furnace
265
is heating. Connect ammeter wires as shown in Fig. 60. The
257
thermostat anticipator should NOT be in the curcuit while mea-
250
suring current. If thermostat has no subbase, the thermostat must
243
be disconnected from R and W wires during current measurement.
237
See thermostat manufacturer's instructions for adjusting heat
231
anticipator and for varying heating cycle length.
225
For an electronic thermostat, set cycle rate for 3 cycles per hour.
220
Step 5—Check Safety Controls
214
209
This section covers the safety controls that must be checked before
205
the installation is complete. The flame sensor, gas valve, and
200
pressure switch were all checked in the Start-up procedure section
196
as part of normal operation.
192
CHECK PRIMARY LIMIT CONTROL
188
This control shuts off gas control system and energizes air-
184
circulating blower motor if furnace overheats. Recommended
180
method of checking this limit control is to gradually block off
178
return air after furnace has been operating for a period of at least
173
5 minutes. As soon as limit control has shut off burners, return-air
170
opening should be unblocked to permit normal air circulation. By
167
using this method to check limit control, it can be established that
164
161 limit is functioning properly and operates if there is a restricted
155 return-air duct or motor failure. If limit control does not function
150
during this test, cause must be determined and corrected.
145
CHECK PRESSURE SWITCH
This control proves operation of draft inducer. Check switch
operation as follows:
1. Turn off 115-v power to furnace.
2. Remove outer furnace door and disconnect inducer motor
from wire harness.
3. Turn on 115-v power to furnace.
4. Set thermostat to "call for heat" and wait 1 minute. When
pressure switch is functioning properly, hot surface igniter
should NOT glow, and control status code LED flashes a
Status Code 31. If hot surface igniter glows when inducer
motor is disconnected, shut furnace down immediately. De-
termine reason pressure switch did not function properly and
correct condition.
5. Turn off 115-v power to furnace.
6. Reconnect inducer motor leads, reinstall main furnace door,
and turn on 115-v power supply.
Step 6—Checklist
1. Put away tools and instruments. Clean up debris.
2. Verify flame-rollout manual reset switch has continuity.
48
FACTORY-
SPEED SHIPPED
CONNECTION
High Cool
Medium High Spare
Medium Low Heat
Low Fan
Common C
OM