Indoor Ventilation Kit
Indoor Installation Kit • Therma Grow
3
CUT DUCT TO PROPER LENGTH,
NO KINKS OR SAGGING
B. Air Inlet Installation and Assembly
(Refer to Fig. 2)
1. From the exterior, slide the air inlet through the
opening. The inlet’s mounting flange must be located
against the flat exterior of the building. Mark and drill
1/8 in. pilot holes at all flange screw holes. Secure
the inlet to the wall with the screws provided. Seal the
inlet’s flange edges.
2. Evenly position the air inlet hood over the inlet at
the exterior of the building. Mark and drill 1/8 in. pilot
holes at all flange holes. Secure the inlet hood to the
exterior wall with screws from kit. Seal the hood’s
flange edges.
3. Assemble the motor with bracket to the air inlet
transition sleeve. Use the nuts and screws from the kit.
Do not tighten at this time
4. Assemble the motor arm to air inlet’s linkage arm. See
detail in Fig. 2. Tighten the screw securely.
5. Push the motor with bracket toward the wall until slots
in bracket stop against mounting screws, and shutters
are fully closed. Securely tighten all motor bracket
screws. See detail in Fig. 2.
6. Mount the air proving switch assembly to the transition
sleeve. Tighten the mounting screws securely.
C. Locating and Installing the Exhaust Fan
1. The exhaust fan must be located at an upper area
of the end wall opposite from the heater, preferably
in an area higher than the heater’s discharge. See
Fig. 3. The exhaust fan does not need to be directly
in line to the heater.
2. Provide a 10 1/4 in. x 10 1/4 in. square and level
opening. Suitable framing may be required for
mounting.
3. Position the kit through the opening from the inside of
the greenhouse. The shutters are gravity operated and
must be installed so the shutters drop to closed after
being lifted open.
-- Check the assembly with a level before installing.
-- Mark and drill 1/8 in. pilot holes at all locations in the
exhaust fan’s mounting flange.
-- Secure with 1/2 in. screws from the kit. See Fig. 4.
-- Seal the appropriate areas to prevent water entry.
D. Wiring the Exhaust Fan and Air Inlet
Shutter Motor to the Heater
1. Select a location for an electrical junction box near
the heater. Mount the junction box.
2. Open the heater’s control box. Remove the hole plug
from the control box base and the wire cap(s) from
the wire(s) labeled TO VENTILATION MOTORS.
See Fig. 5.
3. Route an appropriate length and gauge of electrical
wiring from the junction box up to the bottom of the
control box and through this hole.
4. Connect an appropriate length and gauge of electri-
cal wiring to the leads of the exhaust fan motor and
air inlet shutter motor.
-- Route this wiring to the electrical junction box and
connect it to the wiring leading to the heater’s control
box.
-- Use wire nuts provided.
-- Refer to the appropriate electrical connection diagram
on page 6.
5. Proceed to further wiring instructions, page 4, for
the Therma Grow™ 120 Plus/220 Plus or Therma
Grow™ 120/220 heaters.
