Thermolec Mini Make Up Air - Manual (Page 3)

Attach the unit to a suitable support allowing a minimum 1/2” clearance above the heater. Always install the
unit such that there is sufficient space to remove the cover and the damper assembly if necessary as well as to
remove washable filter for cleaning (fig. 5). The hanger brackets provided (fig. 6) are designed to be used with
threaded rods (not included). Springs may be added to the rods as an option to reduce vibration (not included).
The minimum amount of air required (in cubic feet per minute) to operate
the unit is 30 CFM per kW. A 10 kW unit will require 300 CFM. The fan is
adjusted with the speed control knob located inside the control panel.
Rotating the knob clockwise from the off position starts the fan at maximum
speed and the speed reduces as the knob continues in a clockwise motion.
Actual CFM is based on the static pressure in the duct, for best results
measure the static pressure and then refer to the fan performance chart at
the end of the manual for more detail.
When there is a demand from the current sensor (or a dry contact), the
electronic controller will turn on the fan and start heating. The duct sensor
must be installed in the duct downstream from the mini make up air unit for proper operation. Adjust the blue
square potentiometer on the D23-TF electronic controller with a small screwdriver to control the output tem-
perature. Use the chart below the potentiometer to convert the temperature from Celsius to Fahrenheit.
The duct sensor must be wired to the ‘S’ ‘S’ terminals on the D23-TF. The controller monitors the outlet tem-
perature and alerts of abnormal conditions with a fl ashing light (W) that can be seen on the D23-TF controller,
see Table A below. In the event of a heater failure, such as a tripped manual cutout, the controller will shutdown
the unit to avoid circulating unheated outside air and the warning LED will start fl ashing. If for some reason the
output temperature is too hot, to avoid a potentially dangerous situation, the controller will also shutdown the
unit and fl ash the warning LED accordingly.
Cover opens
this way
Rod
fig. 6
Bracket
Bolt
Lock washer
Flat washer
Filter
Air Outlet
Use supplied Current Sensor
or On/Off contact to start unit.
Air
Inlet
Heater
Fan
Duct sensor
fig. 5
Damper
Controls
OFF
CFM
MAX
MIN
S S T1 L1
10°C 15
30°C 25
D23-TF
+ -
SSR1
24
VAC
COM
+ -
C2 C3 FR
G D/O A A
D F 1 2 W
°C 0 5 10 15 20 25 30 35
°F 32 41 50 59 68 77 86 95
10°C 15
30°C 25
°C 0 5 10 15 20 25 30 35
°F 32 41 50 59 68 77 86 95
Duct
Sensor