ECR RetroAire R90C Installation, operation & maintenance manual - page 13
General
R_ _C
units are straight cool, single stage air conditioners
available with electric or hydronic heat.
R_ _H
units are limited range, single stage heat pump.
Mechanical compression heating (heat pump mode) is
locked out at outdoor temperatures of approximately 35ºF
(1.7ºC) and below. Below these ambient temperatures,
auxiliary electric or hydronic heat will be used.
Microprocessor Control Board
Thermostat and control
connections are made to control board.
A. Two configuration jumpers are located on
board, see Figure 5. Heat Pump Configuration
Jumper is 3 pin jumper.
• Straight
Cool
units R_ _C, the jumper should be
located on the outside two pins.
• Heat
Pump units R_ _H, the jumper should be
located on the inside two pins.
B. Second configuration jumper “TEST” allows for
control’s internal timers to be by-passed for test
purposes. Placing jumper on two pins enables test
mode.
C. Status LED (Light Emitting Diode)
• LED1 is located on center of board. Series of
blinks communicates status of board. Between
blink sequence is separation of approximately 2
seconds. Status Code is listed below.
Trouble
Code
(Blinks)
Status
1
Normal Operation
2
Anti-Short Cycle Timer Active
3
Outdoor Coil Freeze Protection
4
Indoor Coil Freeze Protection
5
Simultaneous “Y” and “W” Call
Initial Power-Up or Power Restoration
When power is applied to unit, either for first time or after
power failure, board will initialize itself.
1.
During initialization, LED1 will be lit continuously for
approximately 5 seconds.
2.
Following initialization, random start timer is initiated.
Timer adds randomly selected 5-120 seconds to start-
up sequence, reducing possibility of multiple units
starting at same time.
3.
Once random start timer has expired, 180 second
Anti-Short Cycle Timer is initiated and Processor Board
Trouble Code LED is set to blink 2 flash code. Timer
prevents compressor from rapid cycling.
4.
After Anti-Short Cycle Timer expires, Processor Board
Trouble Code LED is set to blink 1 blink Trouble Code,
indicating normal operation.
SEQUENCE OF OPERATION
Figure 5 Control Board
LED
Indicator
Light
TEST
Config.
Jumper
Heat
Pump
Config.
Jumper
P/N 240010330, Rev. A [10/15/2013]
13
Made in USA