12
PHYSICAL DATA (cont)
LEGEND
*Weight of 14-in. roof curb.
†Rollout switch lockout is manually reset by interrupting power to unit or
resetting thermostat.
NOTE:
High-static motor not available on size 150 units.
UNIT SIZE 581B
HEAT
090
102
120
150
FURNACE SECTION
Rollout Switch Cutout Temp†
195
195
195
195
Burner Orifice Diameter
(in. ...drill size)
Natural Gas
Std
Lo
.120...31
.120...31
.120...31
.120...31
Med
.120...31
.120...31
.120...31
.129...30
Hi
.120...31
.120...31
.129...30
—
Liquid Propane
Accy
Lo
.096...41
.096...41
.096...41
.096...41
Med
.096...41
.096...41
.096...41
.102...38
Hi
.096...41
.096...41
.102...38
—
Thermostat Heat Anticipator
Setting (amps)
208/230 v and 575 Stage 1
.14
.14
.14
.14
Stage 2
.20
.20
.20
.20
460 v
Stage 1
.14
.14
.14
.14
Stage 2
.20
.20
.20
.20
Gas Input (Btuh)Stage1/Stage 2
Lo
125,000/—
125,000/—
120,000/180,000
180,000/224,000
Med
120,000/180,000
120,000/180,000
180,000/224,000
200,000/250,000
Hi
180,000/224,000
180,000/224,000
200,000/250,000
—/—
Efficiency (Steady State) (%)
82
82
82, 80 (in 250,000 Btuh
heat range)
82, 80 (in 250,000 Btuh
heat range)
Temperature Rise Range
Lo
20-50
20-50
35-65
35-65
Med
35-65
35-65
35-65
40-70
Hi
45-75
45-75
40-70
—
Manifold Pressure (in. wg)
Natural Gas
Std
3.5
3.5
3.5
3.5
Liquid Propane
Accy
3.5
3.5
3.5
3.5
Gas Valve Quantity
1
1
1
1
Gas Valve Pressure Range
Psig
0.180-0.487
0.180-0.487
0.180-0.487
0.180-0.487
in. wg
5.0-13.5
5.0-13.5
5.0-13.5
5.0-13.5
Field Gas Connection
Size (in.)
Lo
1
/
2
1
/
2
3
/
4
3
/
4
Med
3
/
4
3
/
4
3
/
4
3
/
4
Hi
3
/
4
3
/
4
3
/
4
—
HIGH-PRESSURE SWITCH (psig)
Standard Compressor
450 ± 50
500 ± 50
Internal Relief (Differential)
Cutout
428
428
Reset (Auto.)
320
320
LOSS-OF-CHARGE (LOW-PRESSURE)
SWITCH (psig)
Cutout
7 ± 3
Reset (Auto.)
22 ± 7
FREEZE PROTECTION
THERMOSTAT (F)
Opens
30 ± 5
Closes
45 ± 5
OUTDOOR-AIR INLET SCREENS
Cleanable
Quantity...Size (in.)
1...20 x 24 x 1
1...16 x 25 x 1
RETURN-AIR FILTERS
Throwaway
Quantity...Size (in.)
4...16 x 20 x 2
4...16 x 20 x 2
4...20 x 20 x 2
4...20 x 20 x 2
Bhp —
Brake Horsepower