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STATIC AND STATIC WITH MOTORIZED DAMPERS MODELS
Determine Your
Ventilation Needs
installation
How much fresh air do I need? Good air
quality is based in part on the capacity of
the home’s ventilation system.
Usually, the HRV’s capacity is measured in
CFM (Cubic Feet per Minutes) or L/s
(Liters per Seconds) of fresh air being
distributed in the living space. The Room
Count Calculation or the Air Change per
Hour Method shows you how to
determine your ventilation needs.
Air Volume
Needed
installation
In a typical installation there must be an
adequate air volume passing through the
unit in proportion of the pressure from
the heating system.
Exemple: On the warm side*, the air vol-
ume needed is based on a 26’ rigid duct.
On the cold side*, the proportional eqiva-
lent is 18’ of rigid duct.
* Between the model SH and the
forced air system.
**Between the model SH and the
outside intake.
A. Room Count Calculation
B. Air Change per Hour Method
2. Typical Installation
1.Ventilation Needs
LIVING SPACE
Master Bedroom
With Basement
Without Basement
Single Bedroom
Living Room
Dinning Room
Family Room
Recreation Room
Other
Kitchen
Bathroom
Laundry Room
Utility Room
TOTAL cu ft X 0.3 per hr = total
Take total and divide by 60 to get CFM
Number of Rooms
CFM (L/s)
CFM Required
x 20 cfm (10 L/s)
=
x 20 cfm (10 L/s)
=
x 10 cfm (5 L/s)
=
x 10 cfm (5 L/s)
=
x 10 cfm (5 L/s)
=
x 10 cfm (5 L/s)
=
x 10 cfm (5 L/s)
=
x 10 cfm (5 L/s)
=
x 10 cfm (5 L/s)
=
x 10 cfm (5 L/s)
=
x 10 cfm (5 L/s)
=
x 10 cfm (5 L/s)
=
TOTAL ventilation requirement
(add last column) =
25’ x 40’ house with basement
1,000 sq. ft. x 8’ high x 2
(1
st
floor = basement)=
16,000 cu. ft.
16,000 sq. ft. x 0.3 ACH
=
4,800 cu. ft.
4,800 sq. ft. / 60 Minutes
=
80 CFM
1 CFM = 0.47189 L/s
1 L/s = 3.6 m
3
/hr
80 CFM is your ventilation needs
Example:
VENTILATION PERFORMANCE - MODEL SH
0.25
0.20
0.15
0.10
0.05
0.00
Supply
Return
60 70 80 90 100
Ft
3
/min. of HRV (Exhaust)
Supply
SUPPL
Y (“W
.C.)
0.25
0.20
0.15
0.10
0.05
0.00
60 70 80 90 100
Ft
3
/min. of HRV (Fresh Air Intake)
Return
RETURN (“W
.C.)
