Installation and Maintenance Manual

Start-Up and Shutdown
66 RTAE-SVX001B-EN
Ice Making (Running to Ice Making to Running)
Figure 63 shows the transition from normal cooling to Ice
making, back to normal cooling
Figure 63. Sequence of events: ice making (running to ice making to running)
Running
Ice Making Command:
1. Tracer
2. External
3. Front Panel
Running
(Unit is Building Ice)
Ice Making Command
Withdrawn (prior to
ice complete)
Running
Stage and modulate all
compressors in
sequence to full load
(if not already)
Start Compressors and
Circuits per normal
staging – See other
sequence diagrams
Run Inhibit
(Ice to Normal Transition)
Ice To Normal Transition Timer
(fixed 2 mins)
Run Unload, Close EXVs and
Perform Operational Pumpdown (if
regd) then Shutoff Compressors,
Energize Heaters
Ignore Softloading and
SetCLS=100%
Energize Ice Building
Relay
Enforce All Limits and
Running Mode Diagnostics
Head Relief Request
Relay Delay (1 to 60
mins adj)
Evap Leaving
Water Temp Rises
Above the
Differential To Start
Maximum 1:10 to fully
loaded
De-energize Heaters, and
Control EXVs per normal
staging - See other
sequence diagrams
De-energize Heaters, and
Control EXVs per normal
staging - See other
sequence diagrams
Running
Auto
Enforce All Limits and Running Mode Diagnostics
Control Circuit’s
Condenser Fans for Diff
Pressure
Control Circuit’s
Condenser Fans for Diff
Pressure
Turn off both Circuits’
Condenser Fans
Confirm No
Compressor Currents
Close EXVs or leave closed
for Circuits’ Off Cycle
Pre-position EXV, Prestart
Condenser Fans
De-Energize Head
Relief Request and Ice
Building Relay
Energize Head Relief
Request Relay
Continue to Run Evap
Water Pump Throughout