Make Up Air II Installation Manual

05/21/2019 28 EI914
Troubleshooting Solution
The blower is not turning on
 Check unit display. Display should show “FAN OFF” or
temperature screen.
 If screen is blank, check 2A fuse.
 If screen displays the “FAN OFF” screen, unit is not being told to
turn on.
 Verify field low voltage wiring is correct
o CT or R & W
 If screen displays the temperature and blower is not on, check for
power to the blower motor.
 If power present, verify switch R & W IN only closure
between circuit board T18 and T19 (must be active call).
 If no switch closure between T18 and T19, replace circuit
board.
 If power present and switch closure detected, replace
blower.
 If power is not present, check high voltage wiring.
The blower runs in “high
speed” only
 If using the “R & W” terminals (option 1), high speed blower is the
only option.
 If using CTs, ensure correct wiring of CTs, make sure high speed
blower CT only connects to the CT terminal block (TB2) “HI”
input.
 If using “Multi-Spd Setup” option, verify external exhaust blower
motor is not running high speed, once verified, it is suggested you
run through the “Multi-Spd Setup” again to verify correct
programming (see Basic Setup & Configuration section).
The blower runs in “MED
speed” only
 If using CTs to turn this product on, ensure correct wiring of CTs,
make sure MED speed blower CT only connects to the CT
terminal block (TB2) “MED” input.
 If using “Multi-SPD Setup” option, verify external exhaust blower
motor is not running medium speed, once verified, it is suggested
you run through the “Multi-Spd Setup” again to verify correct
programming (see Basic Setup & Configuration section).
The blower runs in “LOW
speed” only
 If using CTs to turn this product on, ensure correct wiring of CTs,
make sure LOW speed blower CT only connects to the CT
terminal block (TB2) “LO” input.
 If using “Multi-Spd Setup” option, verify external exhaust blower
motor is not running low speed, once verified, it is suggested you
run through the “Multi-Spd Setup” again to verify correct
programming (see Basic Setup & Configuration section).
Condensation or frost build-
up on cabinet or ductwork
 Insulate sections of cabinet and ductwork.
Routine Maintenance
Filter – this unit includes an air filter which is a permanent and washable filter.
Suggest at least twice per year removing filter and using standard household water to back flush collected
dust/debris.
 Open small door
 Filter is simply held within channels