HEX080QA Heat Exchanger Instruction Manual
Page 4
User can follow dry contact definition that is Normal Close (N.C.) to
detect abnormal status from pin 10 & pin 11
Definition
N. C
Connection
Pin 10 & Pin 11
Control board, NTC and fan are in
normal status
CLOSE
NTC resistance is over range such as
“open circuit” or “short circuit”
OPEN
Fan speed is lower than 50% of
definition or fan is locked
OPEN
Dry contact max. rating : 75VDC/50mA
LED indicator
INNER FAN / OUTER FAN / STATUS LEDs indicate fan and NTC
sensor status .
Depress "TEST" button to start auto-test of outer and inner fans
running from low to high speed. Turn off by depressing the “TEST” button
again .
INNER FAN
OUTER FAN
STATUS
Normal
GREEN
GREEN
GREEN
Failed*
RED
RED
RED
Normal
(touch TEST / CLEAN)
Blinking
GREEN
Blinking
GREEN
N/A
Failed*
(touch TEST / CLEAN)
Blinking
RED
Blanking
RED
N/A
* FAN failed : Fan speed is lower than 50% of definition or fan is locked
* STATUS Failed : NTC resistance is over range such as “open circuit” or
“short circuit”
