International comfort products R9MSB0601716A Service And Technical Support Manual page 5

NOTICE
DO NOT set low−heat 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.
h. When correct input is obtained, replace cap that
conceals gas valve regulator adjustment screws.
Main burner flame should be clear blue, almost
transparent (See Figure 12.)
i. Remove jumper R to W.
j. Reinstall manifold pressure tap plug from gas valve.
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 1
revolution and note reading. The 2 or 5 cubic feet dial
provides a more accurate measurement of gas flow.
e. Refer to Table 3 for cubic ft. of gas per hr.
f. Multiply gas rate cu ft./hr by heating value (Btuh/cu
ft.) to obtain input. If clocked rate does not match
BLOWER OFF-DELAY
J2 JUMPER
24-V THERMOSTAT
TERMINALS
3-AMP FUSE
LED OPERATION &
DIAGNOSTIC LIGHT
115-VAC(L2)NEUTRAL
CONNECTIONS
COOL
HEAT
BLOWER SPEED
SELECTION TERMINALS
440 04 6000 00
TWINNING AND/OR
COMPONENT TEST
BLOWER OFF-DELAY
TEST/TWIN
HUM
0.5 AMP@24VAC
FUSE 3-AMP
SEC-2 SEC-1
EAC-2 L2
SPARE-1 SPARE-2
SPARE-3
SPARE-1
SPARE-2
SP ARE-3
Figure 2 − Example of Single Stage Furnace Control
Specifications subject to change without notice.
required input from Step 1, increase manifold
pressure to increase input or decrease manifold
pressure to decrease input. Repeat steps b through
e until correct input is achieved. Re−install regulator
seal cap on gas valve.
g. If clocked rate does not match required input from
Step 1, increase manifold pressure to increase
input or decrease manifold pressure to decrease
input. Repeat steps b through e of Step 1 until
correct heat input is achieved. Re--install regulator
seal cap on gas valve.
3. Restore furnace to normal operating condition.
a. Turn gas valve ON/OFF switch to OFF.
b. Remove water column manometer or similar
device from manifold pressure tap.
c. Replace manifold pressure tap plug to gas valve.
d. Turn gas valve ON/OFF switch to ON.
e. Check for gas leaks and verify furnace operation
!
FIRE HAZARD
Failure to follow this warning could result in personal
injury, death, and/or property damage.
Reinstall manifold pressure tap plug in gas valve to
prevent gas leak.
TERMINAL
EAC-1 TERMINAL
(115-VAC 1.0 AMP MAX.)
PR-1
PL2 1
115 VAC (L1) LINE
VOLTAGE CONNECTION
WARNING
HUMIDIFIER TERMINAL
(24-VAC 0.5 AMP MAX.)
TRANSFORMER 24-VAC
CONNECTIONS
PL1-LOW VOLTAGE MAIN
HARNESS CONNECTOR
PL2-HOT SURFACE
IGNITER & INDUCER
MOTOR CONNECTOR
A11619
5