Installation instructions – Ventamatic CX1500 User Manual
Page 2
 
INSTALLATION INSTRUCTIONS
 
THIS GABLE-MOUNTED UNIT IS DESIGNED FOR ATTICS OF AVERAGE SIZE AND OPERATES MOST EFFICIENTLY WHEN AIR 
INTAKES ARE LOCATED AROUND THE EAVES. ALTERNATIVELY, AIR INTAKE MAY BE FROM OPPOSING GABLE VENTS, BUT 
NEVER FROM ROOF OR RIDGE VENTS. AT LEAST 600 SQ. IN OF NET FREE AIR INTAKE IS REQUIRED PER UNIT FOR SAFE 
AND EFFICIENT OPERATION. THE MOTOR OPERATES ON 120 V, 60 HZ, A.C. CURRENT. SEE MOTOR LABEL FOR 
AMPERAGE. 
 
 
THIS UNIT MAY BE MOUNTED BEHIND ANY STATIC WALL VENT, OR MODELS VX1818 OR CX2121 AUTOMATIC SHUTTERS. 
 
Step 
1
Step
3
For new installation or installation behind 
existing louvers, using 2 x 4 studs, frame an 
opening at least 18 ¼-in square (depending on 
stud spacing) on center, on the attic side of the 
gable. 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Step 2 
Cover the opening with a square piece of 
plywood, paneling, or sheetrock, at least 
21 ¼-in square (depending on stud spacing). 
Cut a 15-in diameter hole in the center of this 
panel, to allow the shroud of the fan to enter the 
hole. 
It is important to block off any remaining open 
vent area in the gable. 
 
 
 
 
 
 
With the nuts and bolts furnished, secure the 4
mounting brackets to the shroud and then
fasten the unit to the frame. 
Mounting the long side of the 
L brackets to the shroud may 
better fit your installation and 
also help reduce 
vibration. 
The use of a 
sound-dampening 
barrier, such as
rubber washers or foam stripping will help 
reduce resonance 
in the walls. Seal 
off any gaps 
around 
the fan, 
in order for 
the fan to 
function at 
maximum 
efficiency
.
TIP:
MUCH OF THE PREPARATION, WIRING OF
THERMOSTAT, TESTING, AND MOUNTING TO THE 
FRAME CAN BE COMPLETED BEFORE FINAL 
INSTALLATION IN THE ATTIC.