Specifications

49
• Check for a faulty master or slave MBB. If CCN com-
munications is not working, this alarm will be generated.
T205 (Master and Slave Chiller with Same Address Alert)
— This alert will be generated if Dual Chiller Control is en-
abled, LLEN=ENBL Lead/Lag Chiller Enable (Configura-
tion
→RSET), the chiller has been configured to be the Master
Chiller MSSL=MAST Master/Slave Select (Configura-
tion
→RSET) and both the master chiller and slave chiller have
the same address, CCNA CCN Address (Configura-
tion
→CCN). When this alert is generated the dual chiller con-
trol will be disabled and both units, master and slave, will oper-
ate in stand-alone mode.
If this condition is encountered, check to be sure that the
Slave Chiller address CCNA CCN Address (Configura-
tion
→CCN) matches what is programmed in the Master Chill-
er's configuration for slave address. SLVA Slave Address
(Configuration
→RSET).
T206 (High Leaving Chilled Water Temperature Alert)
—
The criterion for this alert is checked when the unit is ON and
the total available capacity is 100%. The alert is generated
when the leaving chilled water temperature is greater than the
LCWT, High LCW Alert Limit (Configuration
→OPT2) plus
the control point and the leaving chilled water temperature is
higher than it was 1 minute before the current reading. The
LCWT is a delta temperature, not an absolute value. The alert
will automatically reset when the leaving water temperature is
less than the control point, or is less than the control point plus
LCWT minus 5°F (2.8°C).
If this condition is encountered:
• Check building load.
• Check the LCWT, High LCW Alert Limit (Configura-
tion
→OPT2) value.
• Check compressor operation.
• Check water flow.
A207 (Cooler Freeze Protection Alarm)
— This alarm will
be generated when the leaving water temperature is below
BR.FZ, Brine Freeze Point (Set Point Mode
→FRZ). When
this condition is encountered, the machine will enter Mode 16,
and the Chilled Water Pump relay will be energized, even if the
CPC Cooler Pump Control (Configuration Mode
→OPT1) is
OFF. If the machine is equipped with a pump, the pump will
run for a minimum of 5 minutes. The unit will be shut down or
prevented from starting.
The control will allow the machine to reset automatically if
the leaving chilled water temperature rises above the BR.FZ
Brine Freeze Point (Set Point Mode
→FRZ) plus 6°F (3.3°C).
If the alarm is generated again during the same day, it shall be a
manual reset.
If this condition is encountered, check the following items:
• Check the entering or leaving water thermistor for accu-
racy.
• Check water flow rate.
• Check for freezing conditions.
• Check the heat tape and other freeze protection means
for proper operation.
• Check glycol concentration and adjust BR.FZ accord-
ingly.
A208 (EWT or LWT Thermistor Failure Alarm)
— This
alarm will be generated if the entering water temperature, EWT
Entering Fluid Temp (Run Status
→VIEW) is less than the
leaving water temperature, LWT Leaving Fluid Temp (Run
Status
→VIEW) by 3°F (1.7°C) or more for 1 minute after the
circuit has started. When this alarm is generated the chiller is
shut down and prevented from starting. Chilled water pump is
also shut down.
If this condition is encountered, check the following items:
• Check for a correct chilled water flow.
• Check the entering and leaving water thermistors for
accuracy.
• Check to be sure the entering and leaving water thermis-
tors are correctly wired and installed in the proper loca-
tion.
A220 (Condenser Pump Interlock Failure to Close At Start-
Up Alarm) — This alarm will be generated if the unit is con-
figured for D.FL.S=ENBL Enable Cond Flow Switch (Con-
figuration
→OPT1) and condenser flow interlock (if used) cir-
cuit fails to close within 5 minutes of the condenser pump start.
When this alarm is generated the chiller is prevented from
starting or will be shut down; condenser and chilled water
pumps are shut down.
If this condition is encountered, check the following items:
• Check for a condenser pump failure.
• Check for power at the condenser pump.
• Check condenser pump control wiring
• Check condenser strainer for a restriction. Flush or
replace as necessary.
• Check the condenser water flow switch operation.
• Check condenser water flow switch wiring.
• If the unit utilizes a flow regulating valve for head pres-
sure control, consider disabling condenser flow switch
feature.
A221 (Condenser Pump Interlock Opened During Normal
Operation Alarm) — If the unit is configured for D.FL.S=
ENBL Enable Cond Flow Switch (Configuration→OPT1) and
condenser flow interlock (if used) circuit was established and
opens for 15 seconds. When this alarm is generated the chiller
is prevented from starting or will be shut down; condenser and
chilled water pumps are shut down.
If this condition is encountered, check the following items:
• Check for a condenser pump failure.
• Check for power at the condenser pump.
• Check condenser pump control wiring
• Check condenser strainer for a restriction. Flush or
replace as necessary.
• Check the condenser water flow switch operation.
• Check condenser water flow switch wiring.
• If the unit utilizes a flow regulating valve for head pres-
sure control, consider disabling this feature.
A222 (Condenser Pump Interlock Closed When Pump is
Off Alarm) — If the unit is configured for Condenser Pump
Control, D.PM.E Enable Condenser Pump (Configura-
tion
→OPT1) is 1 (On when Occupied) or 2 (On with Compres-
sor), the Condenser Flow Switch is enabled, D.FL.S=ENBL
Enable Cond Flow Switch (Configuration
→OPT1) and con-
denser flow interlock (if used) circuit is closed while the pump
is commanded off, this alarm will be generated. When this
alarm is generated the chiller is prevented from starting.
If this condition is encountered, check the following items:
• Check for a welded condenser pump contactor.
• Check for a faulty condenser pump relay
• Check for a wiring error.
T302 (Strainer Blowdown Scheduled Maintenance Due)
—
This alert is generated when the S.T.DN Strainer Service
Countdown (Run Status
→PM) has expired. Be sure date is cor-
rectly set: MNTH Month of Year, DAY Day of Month, and
YEAR Year of Century (Time Clock
→DATE). Complete the
strainer blowdown. Set S.T.MN Strainer Maintenance Done
(Run Status
→PM) to YES. Then reset the alert.
If this condition is encountered, check the following item:
• Strainer maintenance is required.
T500, T501, T502 (Current Sensor Board Failure — A xx
Circuit A — Alert codes 500, 501, and 502 are for compres-
sors A1, A2, and A3 respectively. These alerts occur when the
output of the CSB is a constant high value. These alerts reset