Marvair ComPac Installation & Operation Manual
12/2017 Rev.16
23
Protection Association Standards 90A and 90B
before
designing and installing duct work.
The duct
system must be engineered to insure sufficient air flow through the unit to prevent over-heating of
the heater element. This includes proper supply duct sizing, sufficient quantity of supply registers,
and adequate return and filter areas. Duct work must be of correct material and must be properly
insulated. Duct work must be constructed of galvanized steel with a minimum thickness of .019
inches. Duct work must be firmly attached, secured, and sealed to prevent air leakage. See section
2.4 for additional duct work requirements.
5.
Clearances:
Note the minimum clearances required for proper operation and service.
MODEL
MIN. CLEARANCE AROUND
SIDES (SINGLE UNIT)
MIN. CLEARANCE BETWEEN
UNITS (TWO UNITS)
MIN. SPACE
ABOVE UNIT
MIN. SPACE
BELOW UNIT
A
B
C
D
12
24 inches (76 cm)
18 inches (46 cm)
24 inches (61 cm)
6 inches (15 cm)
20/24
30 inches (76 cm)
18 inches (46 cm)
24 inches (61 cm)
6 inches (15 cm)
30/36
30 inches (76 cm)
18 inches (46 cm)
24 inches (61 cm)
6 inches (15 cm)
42/48/60
30 inches (76 cm)
30 inches (76 cm)
24 inches (61 cm)
6 inches (15 cm)
72
30 inches (76 cm)
30 inches (76 cm)
12 inches (31 cm)
6 inches (15 cm)
Table 4. Minimum Clearances
6.
Codes:
Make sure your installation conforms to all applicable electrical, plumbing, building, and municipal
codes. Some codes may limit installation to single story structures.
7.
Electrical Supply:
The power supply must have the appropriate voltage, phase, and ampacity for the model selected.
Voltage must be maintained above minimum specified values listed below. Refer to the data sticker
on the unit for ampacity requirements.