Quantech QWC3050T-200T, Installation Operation & Maintenance

Page: 154 / 186

FORM QWC3-NM1
ISSUE DATE: 11/20/2020
SECTION 9 – SERVICE AND TROUBLESHOOTING
QUANTECH
154
This display indicates that the system 1 liquid line sole-
noid valve is OFF, and the output connection from the
microboard is coming from terminal block 10 – pin 3.
Pressing the ↑ (UP) arrow key will energize the liquid
line solenoid valve and OFF will change to ON in the
display as the LLSV is energized. Energizing and de-
energizing outputs may be useful during troubleshoot-
ing.
SERVICE MODE – CHILLER CONFIGURATION
After the Outputs are displayed, the next group of
displays relate to chiller configuration and start/hour
counters. Data logging, soft start, refrigerant type,
pump control selection and expansion valve type all
must be programmed to match actual chiller configura-
tion.
Soft start (disabled), Refrigerant Type
(R410A), and Expansion Valve Type
(Thermostatic), and North American
Feature (Enabled) MUST be properly
programmed or damage to compressors
and other system components may result.
Following is a list of chiller configuration selections, in
order of appearance:
DATA LOGGING MODE = : DO NOT MODIFY
DATA LOGGING TIMER = : DO NOT MODIFY
SOFT START
REFRIGERANT TYPE
EXPANSION VALVE TYPE
REMOTE TEMP RESET OPTION
REMOTE INPUT SERVICE TIME
FEATURE SET
PUMP CONTROL SELECTION
SYS 1 HOURS
SYS 2 HOURS
SYS 1 STARTS
SYS 2 STARTS
The last displays shown on the above list are for the ac-
cumulated run and start timers for each system. All val-
ues can also be changed using the ↑ (UP) and ↓ (Down)
arrow keys, but under normal circumstances would not
be required or advised. After the last start display, the
microprocessor will display the first programmable
value under the PROGRAM key.
SERVICE MODE – ANALOG AND DIGITAL
INPUTS
After entering Service Mode (PROGRAM
↑↑ ↓↓)
,
all digital and analog inputs to the microboard can be
viewed by pressing the OPER DATA key. After pressing
the OPER DATA key, the ↑ (UP) arrow and ↓ (DOWN)
arrow keys are used to scroll through the analog and
digital inputs.
Following is the order of analog and digital inputs that
will appear when sequenced with the
↓ (
Down) arrow
key:
(Analog inputs)
SYS 1 SUCT PRESSURE
UNIT TYPE
SYS 1 *DISCH PRESSURE
SYS 1** SUCTION TEMP.
SYS 2** SUCTION TEMP.
AMBIENT AIR TEMP.
LEAVING LIQUID TEMP.
RETURN LIQUID TEMP.
SYS 2 SUCTION PRESSURE
SYS 2 SPARE
SYS 2 *DISCH PRESSURE
SYS 1 MTR VOLTS
SYS 2 MTR VOLTS
(Digital inputs)
PWM TEMP RESET INPUT
LOAD LIMIT INPUT
FLOW SW / REM START
SPARE
SINGLE SYSTEM SELECT
SYS 1 MP / HPCO INPUT
SYS 2 MP / HPCO INPUT
* The discharge pressure transducer is optional on some models.
** The suction temp. sensor is on EEV units only.
The analog inputs will display the input connection,
the temperature or pressure, and corresponding input
voltage such as:
S Y S 1 S U C T P R J 7 - 1 0
2 . 1 V D C = 8 1 P S I G
This example indicates that the system 1 suction pres-
sure input is connected to plug 7 – pin 10 (J7-10) on
the I/O board. It indicates that the voltage is 2.1VDC
which corresponds to 81 PSIG (5.6 bars) suction pres-
sure.