Water Pumps Control - Carrier SmartVu Control Manual

the HMI. Both Ontime counters roll over to 0 at 500,000 hours. Manual changes to SERVICE ONTIME
f rom the screen are permitted at any time.
The chiller also maintains a start-to-start timer and a stop-to-start timer. These timers limit how soon the
chiller can be started. TIMERs are displayed on the RUNTIMES screen and can be configured in
CONFIGURATION MENU/ GENERAL CONFIGURATION screen.
These timers must expire before the chiller starts. If the timers have not expired the RUN STATUS
parameter on the Default and GENERAL PARAMETERS screen reads TIMEOUT.
The other two timers displayed on the RUNTIME screen are 'swift restarts in 1 hour' and'recy startup in
4 hours'. The f irst defines a maximum of 4 times of swift restarts can be applied for the chiller in 1 hour.
The other clarifies that recycle restarts should be less than 5 times in 4 hours, otherwise system will not
pass prestart check.
5.18.

Water Pumps Control

Note: In order to energize the chilled and condenser pump to prevent evaporator and condenser tube
freeze-up, the Hydraulic System should be enabled first (this can be configured in CONFIGUATION MENU/
FACTORY screen).
Evaporator Freeze Prevention
When the evaporator saturated refrigerant temperature or evaporator ref rigerant temperature is less than
the EVAP REFRIG TRIPPOINT plus the REFRIG OVERRIDE DELTA T (configurable from 2^F to 5^ F
(1.1^C to 2.8^C) in CONFIGURATION MENU/ PROTECTIVE LIMIT CONFIG screen), event
"OVERRIDE – LOW EVAP REFRIG TEMP" will occur.
In all running status, if either of the following conditions is true:
- Evaporator saturated refrigerant temperature is equal to or less than the EVAP REFRIG
TRIPPOINT (33° F or 0.6° C f or water, configurable for brine in CONFIGURATION MENU/
PROTECTIVE LIMIT CONFIG screen) plus one degree F.
- Evaporator refrigerant temperature is equal to or less than the EVAP REFRIG TRIPPOINT.（If
chiller is startup with high lift, High Lift Startup Flag is on, this condition will be ignored）
- Leaving chilled water temperature or entering chilled water temperature is less than EVAP
REFRIG TRIPPOINT plus 1 degree F.
Then Protective Limit Alarm evaporator freeze will be displayed, the unit will shut down, if chiller is in
recycle mode then it will transition to TRIPOUT, and the CHILLED WATER PUMP will remain on. The
alarm will be clearable when
- Evaporator saturated refrigerant temperature, evaporator refrigerant temperature, Leaving chilled
water temperature and entering chilled water temperature rise 5^F (2.8^C) above the EVAP
REFRIG TRIPPOINT.
Condenser Pump Control
SRDC-UG-2-14-000
19 Series Carrier®
–
TM
SmartVu
Controls IOM
REVISION DATE
2.3 Dec 4, 2020
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