For PSC systems, the ½ hp motor is equipped with 4 speeds. The unit is set for mid-fire temp rise @ 65ºF. See table for proper blower motor set up:

OH6FA072D48

ALTERATIONS REQ’D FOR A/C @ DESIGN EXTERNAL STATIC PRESSURE

 

COOLING UNIT

HTG Speed by Input

 

 

Recommended CLG Speed

 

 

 

 

Low

Mid

High

 

 

 

 

 

 

Fire

Fire

Fire

 

 

 

24,000

 

Low

ML

MH

 

Low

 

30,000

 

Low

ML

MH

 

Med Low

 

36,000

 

Low

ML

MH

 

Med High

 

42,000

 

Low

ML

MH

 

Med High

 

48,000

 

Low

ML

MH

 

High

 

Speed Tap\ Static

 

 

 

Furnace Airflow (CFM) vs. External Static pressure (in. WC.)

 

 

Pressure

0.1

 

 

0.2

0.3

0.4

0.5

0.6

 

0.7

 

Low

930

 

 

915

912

910

822

774

 

730

 

ML

1155

 

 

1152

1130

1126

1085

1042

 

920

 

MH

1442

 

 

1432

1418

1382

1334

1293

 

1230

 

High

1802

 

 

1762

1705

1635

1569

1493

 

1428

 

 

Furnace Motor Current Draw (Amps) vs. External Static pressure (in. WC.)

Low

3.3

 

 

3.1

3.0

2.9

2.6

2.5

 

2.4

 

ML

4.2

 

 

4.0

3.9

3.7

3.6

3.3

 

3.0

 

MH

5.4

 

 

5.2

5.0

4.7

4.4

4.2

 

4.0

 

High

6.6

 

 

6.4

6.0

5.7

5.5

5.2

 

5.0

 

 

 

 

 

 

 

 

 

 

 

 

Speed Tap\ Static

 

High Fire Temperature Rise vs. External Static pressure (in. WC.)

 

 

Pressure

0.1

 

 

0.2

0.3

0.4

0.5

0.6

 

0.7

 

Low

90

 

 

91

91

92

101

108

 

114

 

ML

72

 

 

72

74

74

77

80

 

91

 

 

 

MH

58

 

 

58

59

60

62

64

 

68

 

 

 

 

High

46

 

 

47

49

51

53

56

 

58

 

 

 

 

 

 

 

 

 

 

Speed Tap\ Static

 

Mid Fire Temperature Rise vs. External Static pressure (in. WC.)

 

 

 

 

 

 

 

 

 

 

 

 

 

Pressure

0.1

 

0.2

0.3

0.4

0.5

0.6

 

0.7

 

Low

 

 

 

 

 

 

 

 

 

91

 

72

 

 

73

73

73

81

86

 

 

ML

58

 

 

58

59

59

61

64

 

72

 

 

 

 

MH

46

 

47

47

48

50

52

 

54

 

High

37

 

38

39

41

42

45

 

47

 

 

 

 

 

 

Speed Tap\ Static

 

Low Fire Temperature Rise vs. External Static pressure (in. WC.)

 

 

Pressure

0.1

 

0.2

0.3

0.4

0.5

0.6

 

0.7

 

Low

60

 

 

61

61

61

68

72

 

76

 

 

 

 

ML

48

 

48

49

49

51

53

 

 

 

 

60

 

MH

39

 

39

39

40

42

43

 

45

 

High

31

 

32

33

34

35

37

 

39

 

Figure 19A: Heating speed by input

33

Page 36
Image 36
Thermo Products OHFA199DV5B, OHFA199DV5R operation manual OH6FA072D48, High