Btuh To 140,000 Btuh - Carrier bryant 915SB Installation, Start-Up, Operating And Service And Maintenance Instructions

915SB: Installation, Start-up, Operating and Service and Maintenance Instructions
Check Safety Controls
The flame sensor, gas valve, and pressure switch were all checked in the
Start-up procedure section as part of normal operation.
1. Check Main Limit Switch
This control shuts off combustion system and energizes
air-circulating blower motor, if furnace overheats. By using this
method to check the temperature limit control, it can be established
that the limit is functioning properly and that the limit will operate
if there is a restricted return-air supply or motor failure. If the limit
control does not function during this test, the cause must be
determined and corrected.
a. Run furnace for at least 5 minutes.
b. Gradually block off return air with a piece of cardboard or sheet
metal until the limit trips.
c. Unblock return air to permit normal circulation.
d. Burners will re-light when furnace cools down.
2. Check Pressure Switch(es)
This control proves operation of the draft inducer blower.
a. Turn off 115-v power to furnace.
b. Disconnect inducer motor lead wires from wire harness.
c. Turn on 115-v power to furnace.
d. Set thermostat to "call for heat" and wait 1 minute. When low
pressure switch is functioning properly, hot surface igniter
should NOT glow and control diagnostic light flashes a status
code 31. If hot surface igniter glows when inducer motor is
disconnected, shut down furnace immediately.
e. Determine reason low pressure switch did not function properly
and correct condition.
f. Turn off 115-v power to furnace.
g. Reconnect inducer motor wires, replace door, and turn on 115-v
power.
h. Blower will run for 90 sec before beginning the call for heat
again.
i. Furnace should ignite normally.
Checklist
1. Put away tools and instruments. Clean up debris.
2. Verify that the jumper is removed from the TEST/TWIN terminal.
Verify that there is nothing plugged into the PLT connector. (Note:
If there is a jumper connector plugged into PLT, remove it and
discard.) See Fig. 38.
3. Verify that the Blower/Heat Off Delay jumpers are set as desired.
See Fig. 38 and Fig. 73.
4. Verify that there are no unsealed openings in the blower shelf or
casing.
5. Verify that the blower (lower door in upflow position) and control
("Main" or upper door in upflow position) doors are properly
installed.
6. Verify that the Status LED glows. If not, check that the power
supply is energized and that the blower door is secure. See
to interpret diagnostic codes.
7. Cycle test furnace with room thermostat to be sure that it operates
properly with the room thermostat. Check all modes including
Heat, Cool and Fan.
8. Check operation of accessories per manufacturer's instructions.
9. Review Owner's Manual with owner.
10. Attach entire literature packet to furnace.
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
Table 21 – Orifice Size and Manifold Pressure (in. w.c.) for Gas
(TABULATED DATA BASED ON 20,000 BTUH PER BURNER, DERATED 2%/1000 FT (305M) ABOVE SEA LEVEL)
ALTITUDE A V G . G
RANGE HEAT VALUE
AT ALTITUDE
ft (m)
(Btu/cu ft)
900
0 925
(0) 950
975
to 1000
1025
2000 1050
(610) 1075
1100
U.S.A. 800
2001 (611) 825
to 850
3000 (914) 875
900
Canada 925
2001 (611) 950
to 975
4500 (1372) 1000
775
3001 800
(915) 825
850
to
875
4000 900
(1219) 925
950
750
4001 775
(1220) 800
825
to
850
5000 875
(1524) 900
925
725
5001 750
(1525) 775
800
to
825
6000 850
(1829) 875
900
675
6001 700
(1830) 725
750
to
775
7000 800
(2133) 825
850
Table 21 (Continued) -Orifice Size and Manifold Pressure (in. w.c.)
(TABULATED DATA BASED ON 20,000 BTUH PER BURNER, DERATED 2%/1000 FT (305M) ABOVE SEA LEVEL)
ALTITUDE A V G . G
RANGE HEAT VALUE
AT ALTITUDE
ft (m) (Btu/cu ft)
650
7001 675
(2134) 700
725
to
750
8000 775
(2438) 800
825
Fig. 71
625
8001 650
(2439) 675
700
to
725
9000 750
(2743) 775
9001 600
(2744) 625
650
to
675
10000 700
(3048) 725
* Orifice numbers shown in BOLD are factory-installed.
53
Input Rate

40,000 BTUH to 140,000 BTUH

SINGLE-STAGE FURNACE
A S S P E C F I C I G R A V T I Y O F
0.58 0.60
Orifice Manifold Orifice Manifold Orifice
No. Pressure No. Pressure No.
43 3.8 42 3.2 42
43 3.6 43 3.7 43
43 3.4 43 3.5 43
44 3.7 44 3.8 43
44 3.5 44 3.6 44
44 3.3 44 3.5 44
44 3.2 44 3.3 44
45 3.7 45 3.8 44
46 3.7 46 3.8 45
42 3.4 42 3.5 42
43 3.8 42 3.3 42
43 3.6 43 3.7 42
43 3.4 43 3.5 43
44 3.7 44 3.8 43
44 3.5 44 3.6 44
44 3.3 44 3.4 44
44 3.2 44 3.3 44
44 3.0 44 3.1 44
42 3.3 42 3.4 42
43 3.8 42 3.2 42
43 3.6 43 3.7 43
44 3.8 43 3.5 43
44 3.6 44 3.7 43
44 3.4 44 3.5 44
44 3.2 44 3.4 44
44 3.1 44 3.2 44
42 3.3 42 3.4 42
43 3.7 43 3.8 42
43 3.5 43 3.6 43
44 3.8 43 3.4 43
44 3.5 44 3.7 44
44 3.3 44 3.5 44
44 3.2 44 3.3 44
44 3.0 44 3.1 44
42 3.2 42 3.3 42
43 3.7 43 3.8 42
43 3.4 43 3.5 43
44 3.7 44 3.8 43
44 3.5 44 3.6 44
44 3.3 44 3.4 44
44 3.1 44 3.2 44
44 2.9 44 3.0 44
42 3.4 42 3.5 42
42 3.2 42 3.3 42
43 3.6 43 3.7 43
43 3.4 43 3.5 43
44 3.6 44 3.7 43
44 3.4 44 3.5 44
44 3.2 44 3.3 44
44 3.0 44 3.1 44
for Gas Input Rate (Cont.)
40,000 BTUH to 140,000 BTUH
SINGLE-STAGE FURNACE
A S S P E C F I C I G R A V T I Y O F
0.58 0.60
Orifice Manifold Orifice Manifold Orifice
No. Pressure No. Pressure No.
42 3.4 42 3.5 42
43 3.8 42 3.2 42
43 3.5 43 3.7 43
44 3.8 43 3.4 43
44 3.5 44 3.7 44
44 3.3 44 3.4 44
44 3.1 44 3.2 44
44 2.9 44 3.0 44
42 3.4 42 3.5 42
43 3.8 42 3.2 42
43 3.5 43 3.6 43
44 3.7 43 3.4 43
44 3.5 44 3.6 44
44 3.3 44 3.4 44
44 3.0 44 3.2 44
42 3.3 42 3.4 42
43 3.7 42 3.2 42
43 3.5 43 3.6 43
44 3.7 44 3.8 43
44 3.4 44 3.5 44
44 3.2 44 3.3 44
N A T U R A L G A S
0.62 0.64
Manifold Orifice Manifold
Pressure No. Pressure
3.3 42 3.4
3.8 42 3.2
3.6 43 3.7
3.4 43 3.6
3.8 43 3.4
3.6 44 3.7
3.4 44 3.5
3.3 44 3.4
3.8 44 3.2
3.6 42 3.7
3.4 42 3.5
3.2 42 3.3
3.7 43 3.8
3.5 43 3.6
3.8 43 3.4
3.6 44 3.7
3.4 44 3.5
3.2 44 3.3
3.5 42 3.6
3.3 42 3.4
3.8 42 3.2
3.6 43 3.7
3.4 43 3.5
3.7 44 3.8
3.5 44 3.6
3.3 44 3.4
3.5 42 3.6
3.3 42 3.4
3.7 43 3.8
3.5 43 3.6
3.8 43 3.4
3.6 44 3.7
3.4 44 3.5
3.2 44 3.3
3.4 42 3.5
3.2 42 3.3
3.7 43 3.8
3.4 43 3.5
3.7 44 3.8
3.5 44 3.6
3.3 44 3.4
3.1 44 3.2
3.6 42 3.8
3.4 42 3.5
3.8 42 3.3
3.6 43 3.7
3.4 43 3.5
3.6 44 3.7
3.4 44 3.5
3.2 44 3.3
A11253A
N A T U R A L G A S
0.62 0.64
Manifold Orifice Manifold
Pressure No. Pressure
3.6 42 3.7
3.3 42 3.4
3.8 42 3.2
3.5 43 3.6
3.8 43 3.4
3.5 44 3.7
3.3 44 3.4
3.1 44 3.2
3.6 42 3.7
3.3 42 3.4
3.7 42 3.2
3.5 43 3.6
3.7 44 3.8
3.5 44 3.6
3.3 44 3.4
3.6 42 3.7
3.3 42 3.4
3.7 43 3.8
3.4 43 3.5
3.7 44 3.8
3.4 44 3.5
A11253B