All installations and services must be performed by qualified service personnel.
13
OH5 2-STAGE
OH5 2-STAGE
Factory shipped
settings
G. ECM SPECIFIC REPLACEMENT PARTS
Part Name
OH5/OH2
OH11
OL5/OL2
OL11
OC5/OC2
OH5
2-STAGE
ECM Motor
AOPS7443/
AOPS7449
AOPS7444
AOPS7445/
AOPS7450
AOPS7446
AOPS7448/
AOPS7447
AOPS7454
Control Board
350915
350915
350915
350915
350915
350184
Motor Power Harness
350917
350917
350918
350918
350917
350917
Motor Control Harness
350920
350920
350921
350921
350920
350183
Burner Harness
350916
350916
350916
350916
350928
350182
Transformer
350464
350464
350464
350464
350464
350464
III. ECM TROUBLE SHOOTING
A. DIAGNOSTC FEATURES
The control board is equipped with 4 green Input Status LEDs and 1 red Board Status LED. These are intended to
provide a quick view into furnace performance without requiring a voltmeter.
The green Input Status LEDs are driven by the “Y”, “W”, “G”, and “DEHUM” inputs and are located directly
below those inputs. They will light to indicate the presence of these signals.
SW1
SETTING
TONS
CFM
COOL LOW
6 OFF
5 OFF
4 ON
2
726
352
6 OFF
5 OFF
4 ON
2.5
924
462
6 OFF
5 ON
4 ON
3
1276
638
6 ON
5 OFF
4 OFF
3.5
1474
726
6 ON
5 OFF
4 ON
4
1600
814
SW1
SETTING
LOW FIRE
CFM RISE
HIGH FIRE
CFM
RISE
3 OFF
2 ON
1 OFF
800
81
1008
78
3 OFF
2 ON
1 ON
905
72
1121
70
3 ON
2 OFF
1 OFF
960
68
1200
66