Recommended Roof Opening & Weights
A
EXHAUST
INLET
SUPPLY
OUTLET
1.63
B
1.63
Position the unit roof opening such that the supply
discharge and exhaust inlet of the unit will line up with
the corresponding ductwork. Be sure to allow for the
recommended service clearances when positioning
the opening (see Service Clearances). Do not face the
outdoor air intake of the unit into prevailing wind and
keep the intake away from any other exhaust fans.
Likewise, position the exhaust discharge opening away
from outdoor air intakes of any other equipment.
When cutting only duct openings, cut opening 1-inch
(25 mm)
larger than duct size to allow clearance for
installation. Area enclosed by roof curb must comply
with clearance to combustible materials. If the roof is
constructed of combustible materials, area within the
roof curb must be ventilated, left open, or covered with
non-combustible material which has an “R” value of
at least 5. If area within curb is open, higher radiated
sound levels may result.
Where the supply or warm air duct passes thru a
combustible roof, a clearance of one inch must be
maintained between the outside edges of the duct
and combustible material in accordance with NFPA
Standard 90A.
Unit Size
A
B
Approx.
Weight (lbs.)
ERVe-20
22
37
950
ERVe-35
25
44.5
1270
ERVe-45
27
51.5
1500
ERVe-55
27
60
1960
All dimensions are in inches. These weights include sheet
metal weights added together with the largest motors,
blowers and accessories for the units.
Recommended Service Clearances
Unit Size
A
B
C
D
ERVe-20
24
24
42
35
ERVe-35
32
24
48
43
ERVe-45
32
24
54
43
ERVe-55
32
24
60
44
All dimensions are in inches.
Access Panel Description and Location
1
Outdoor air filters
Frost control
Outdoor air sensors
Preheater and controls
Outdoor air intake damper
2
Supply blower and motor
3
Electric control center
Main disconnect
4
Energy wheel cassette
Exhaust air filters
Exhaust air intake damper
5
Exhaust blower and motor
Outdoor air intake damper actuator
Service Clearances
ERVe units require minimum clearances to perform
routine maintenance, such as filter replacement, energy
wheel cassette inspection, and fan belt adjustment.
Blower and motor assemblies, energy recovery wheel
cassette and filter sections are always provided with a
service door or panel for proper component
access.
D
C
B
A
D
CLEARANCE
CLEARANCE
1
2
3
4
5
Energy Recovery Ventilator
5
®
