13
Measure Temperature Rise
1. After 20 minutes of heating operation, measure the furnace
temperature rise. Take air temperature readings in both the
return air ducts and the heated air ducts.
NOTE: If more than one run of return or heated air ducts is
used, air temperature measurements should be taken in each
duct. These measurements can be converted to an average
to obtain the temperature rise of the whole system.
2. If the furnace doesn't maintain temperature rise within the
range shown on the furnace rating plate, adjust the blower
speed. See the appropriate “Adjust Blower Speed” section
for your model.
Shut Down
If the construction will continue or the package unit will not be
used for a period of time, follow the shut down procedure.
1. Set the room thermostat to the lowest setting.
2. Disconnect power.
3. Remove burner access panel.
4. Turn off the gas supply at the manual gas shutoff valve.
5. Replace the burner access panel.
Gas Control Valve
Adjusting Airflow for Variable-Speed Motor
Model
Motor
HP
ADJUST
Setting
HEAT
Setting
Cooling CFM @ .50 Static
Nominal
Cooling
kBTU
Heating
Input
kBTU
COOL
Setting A
COOL
Setting B
COOL
Setting C
COOL
Setting D
24, 30
68
¹⁄₃
NORM
A
1,000
800
600
900
36
68
¹⁄₂
NORM
B
1,200
1,000
800
1,100
36
90
¹⁄₂
NORM
A
1,200
1,000
800
1,100
42, 48, 60
83
³⁄₄
NORM
C
1,800
1,600
1,400
1,200
42, 48, 60
110
³⁄₄
NORM
C
1,800
1,600
1,400
1,200
42, 48, 60
138
³⁄₄
NORM
A
1,800
1,600
1,400
1,200
Blower Speed Chart for Variable-Speed Motor
Unit
Factory-Shipped Settings
Cooling
Input
Heating
Input
Adjust
Heat
(BU)
Cool
(BK)
24
68
NORM
A
B
30
68
NORM
A
A
36
68
NORM
B
A
36
90
NORM
A
A
42
83
NORM
C
C
42
110
NORM
C
C
48
83
NORM
C
B
48
110
NORM
C
B
48
138
NORM
A
B
60
83
NORM
C
A
60
110
NORM
C
A
60
138
NORM
A
A
A. Regulator adjusting cap
B. NPT inlet
C.
¹⁄₈
" NPT inlet pressure tap
D.
¹⁄₈
" NPT outlet pressure tap
E. NPT outlet
F. Gas control switch
A
B
C
D
E
F