Control Board Status Leds; Selectable Furnace/Air Handler Interlock - Nu-Air NU0103 Operating, Maintaining & Installing

7 Control Board Status LEDs

The control board is equipped with LEDs which indicate the unit's current state of operation.
CONDITION
NO LED
UNIT OFF
STANDBY
EXHCHANGE LOW SPEED
EXCHANGE HIGH SPEED
DEFROST
RECIRCULATION LOW SPEED*
RECIRCULATION HIGH SPEED*

8 Selectable Furnace/Air Handler Interlock

You may choose on the unit control board to interlock whenever the HRV/ERV is operating at
any speed, or just high speed. Position 5: interlock at any HRV speed; Position 6: interlock at
HRV high speed only.
One jumper must be present in
jumper range 1-4 and in jumper
range 5-8.
Do not alter jumper set 3.
Rev 2.3 July 17, 2017
LED AND STATUS
UNIT/TRANSFORMER IS NOT POWERED
Red is off, Green is blinking slow, every 1 s. Also indicates processor is
programmed and running.
Green is OFF. Red led is blinking slow, every 1 s.
Green ON. Red blinking slow, every 1 s.
Green ON. Red blinking fast.
Green ON, Red ON. (Appears Yellow)
Red led ON, Yellow blinking slow, every 1s.
Red led ON, Green led blinking fast.
1 2 3 4 5
(factory setting shown)
6 7 8
16