9
MICROPROCESSOR CONTROL
SP007-30
J.
Line Voltage.
Line voltage is input and output from the circuit board on the terminals marked “L1” and “L2”.
There are four terminals marked “L1”, the purpose of each is as follows. One is “L1” input to the board while
the remaining three are outputs to one side of the Transformer, Crankcase Heater and the Outdoor Fan Motor.
There are two terminals marked “L2”. One is “L2” line voltage input to the board while the other is output to the
Transformer.
K.
Anti-Recycle Delay Timer.
The outdoor board provides an “anti-recycle delay” which is 3 minutes in the cooling
mode and 6 minutes in the heating mode.
L.
Time Shortening.
By moving the defrost jumper to the “test” position time shortening of “timing sequences”
can be accomplished. Timeouts are reduced as follows when the jumper is in the test position:
1. Anti-recycle
36 seconds
2. CCH Cycles
24 seconds
3. Defrost Interval
24 seconds
4. Compressor Run
1 second
5. Low Pressure bypass 12 seconds
M.
Last Fault Memory Recall.
The outdoor board (TDICM3315) maintains a memory of the “last fault” which can be
recalled by moving the defrost jumper to the “test” position and viewing the “status” LED display. Only one
fault can be memorized. The fault can be cleared by turning off and resetting line voltage to the outdoor unit.
N.
LED Function.
The board has four LED’s which provide the following function:
1.
“STATUS” LED
indicates normal operation or faults as follows:
2.
“CCH” LED
indicates that the Crankcase heater is energized.
3.
“2” LED
indicates that the indoor unit is calling for compressor operation, 12VDC is present on control wire #2.
4.
“3” LED
indicates that the indoor unit is set to the Heating Mode. The reversing valve will be energized
(except during defrost). 12VDC is present on control wire #3.
O.
Serial Number.
Consists of 7 digits which have the following meaning:
Serial Number: 0 161 253
Consecutive Unit Number
Julian Calendar Day
Year (0=2000, 1=2001..)
P.
Production Code.
Identifies the exact day of manufacturing. Read from left to right using BLACKHORSE acronym.
Q.
Circuit Board Manufacture Numbers.
To date two versions of outdoor circuit boards have been manufactured.
1. T7I CM2 315: Original board. Does not memorize last fault code.
2. T7I CM3 315: Memorizes last fault. Provides improved protection for 12VDC circuit from EMC.
LED FLASHES
INDICATION OF CONDITION
Off
Normal Operation, no fault, no “call”
Constant On LED
Anti-recycle delay active. If the
HPSS or LPS opens the anti-recyle
will activate for 3 to 6 minutes
before the fault can be displayed.
1 Flash Sequence
Defrost Sensor Closed
2 Flash Sequence
High Pressure Safety Switch Open
3 Flash Sequence
LATS Open
4 Flash Sequence
Low Pressure Safety Switch Open