Mammoth 800 to 5500 CFM: Dedicated Outdoor Air System with Enthalpy Wheels (VHC) - Manual (Page 7)

MAMM-VHC-IOM-1A (JANUARY 2013) 7
Open access doors or panels and remove all packaging
from the unit. Note that there is packaging for wheel sup-
port during shipping. Removal of all packaging is critical.
Internal Packaging
Refer to Table 1 for the effect of undersized equivalent duct
diameter.
Calculate Equivalent Duct Diameter
The equivalent duct diameter of the fan outlet.
= (4ab + n)
0.5
= (4 x 13.5 x 9.5) 0.5
n
= 12.75
= ~13
So the straight duct length required would be:
= 2.5 x 13
= 32.5” long [2.7 feet]
Intake and exhaust hoods for these models are shipped
separately from the unit. To install hoods see Appendix B .
A quick connect for the damper motors is provided to con-
nect to the main body of the unit. Make sure that all screws
are secured to maintain proper support and keep seals
water-tight.
Handles for lift off exterior access panels with screw door
fasteners are provided but must be installed on site. Han-
dles and fasteners are secured inside the unit.
Hood Installation
Access Panels
IMPORTANT
Securing door fasteners too tightly has negative effects on
the door gasket and should be avoided.
Table 1: Effect of Undersized Equivalent Duct Diameter
Pressure
recovery
No Duct
12%
Effective
Duct
25%
Effective
Duct
50%
Effective
Duct
100%
Effective
Duct
0% 50% 80% 90% 100%