Trane CSRA025FAF0 Installation Operation & Maintenance page 13

CSRA-SVX02A-EN
General
Information
3. Turn "Off" and lockout all of the compressors and initiate a manual reset
diagnostic.
Loss-of-Flow (Solution) Protection (Standard)
The factory installed solution flow switch is wired to the CGM. If it opens for
more than 6 continuous seconds when the pump is requested to be "On", an
auto reset diagnostic will be initiated. If no compressors are operating, they
will be inhibited from starting. Any time the compressors are operating, they
will be turned "Off". Once flow has been reestablished, full unit operation will
be allowed.
In addition, a low pressure cutout and the entering (EST) and leaving
solution temperature (LST) sensors provide loss of flow protection for the
unit.
When there is a cooling demand, the CGM compares the EST to the LST. If
the EST is 2°F or more below the LST, the chiller is stopped and a manually
reset diagnostic is initiated. This input has priority over all other commands
received by the CGM.
Low Ambient Start (Standard)
Is accomplished by utilizing an additional low pressure cutout (LPC) that is
ignored at start-up for varying periods of time, depending on the prevailing
ambient temperature. The relationship between this variable time period and
the ambient temperature is linear from a maximum of 5 minutes at 0°F to a
minimum of 30 seconds at 65°F. The bypass time is initiated each time a
compressor is started on a refrigerant circuit when no other compressor on
that circuit is operating. No additional compressors will be allowed to operate
within that circuit until the bypass time has expired.
Chiller Solution Pump Output Relay (Standard)
A Solution Pump binary output (Form C) relay is located on the CGM which
may be used to control the chiller solution pump.
If the Chiller Solution Pump Mode, at the Human Interface Module, is set to
"On", the Solution Pump will run continuously.
If the Chiller Solution Pump Mode, at the Human Interface Module, is set to
Auto, the Solution Pump will be turned "Off":
1. when the unit is stopped (Unit Stop or External Auto/Stop)
2. during the unit's Power On Delay Time
3. when the primary control states are:
Ice Rebuild Delay
Ice Building Complete
A Solution Pump "Off Delay" Time may be programmed to allow the Solution
Pump to remain "On" after a shut down request has been received. The
delay is adjustable between 0.5 minutes and 10 minutes after an "Off" state
is initiated. The Solution Pump will always run for this delay time when
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