Unit installation

Diagnostics
SCXF-SVX01K-EN 101
UCM Reaction:The minimum airflow control function is
disabled.The outside air damper minimum position
function reverts to using the O/A flow compensation
function if O/A flow compensation is enabled or to the
default minimum position function if O/A flow
compensation is disabled or not available.
Reset Required: (PAR) An automatic reset occurs after the
designated space pressure transducer sends a signal
within range for 10 continuous seconds.
VOM Communications Failure
Problem:The RTM has lost communication with the VCM.
Check: Field/unit wiring between RTM and VCM.
Reason for Diagnostic:The RTM has lost communications
with the VOM.
UCM Reaction: Ventilation override actions will not be
allowed, and the VO Output relay will be deenergized.
Reset Required: (PAR) An automatic reset occurs after
communication has been restored.
W
WSM Communications Fail
Problem:The RTM has lost communication with theWSM.
Check: Field/unit wiring between RTM and WSM.
Reason for Diagnostic: RTM has lost communication with
WSM.
UCM Reaction: UCM will react as if a freezestat has
occurred by issuing:
• “all heat on” or “mod output full open” request to “heat
control”
• A “fan off” request to “supply fan control”
• “close damper” request to “economizer actuator
control”
• Water pump to turn on and position all water valves to
provide maximum flow through all water source heat
exchangers
• Disables preheat function if WSM mixed air temp sensor
is selected as preheat sensor
Reset Required: An automatic reset occurs after one
complete set of IPC packets is received.
WSM Mixed Air Temp Sensor Fail
b. Activation Conditions: temperature <-50°F or
temperature >209°F, and sensor is selected for use by
“waterside economizer temperature enable function” or
“preheat function”
c.Time to React: 10 sec < T < 20 sec
e. Actions to be Initiated: “waterside economizer
temperature enable function” uses supply air cooling
setpoint instead of mixed air temperature. If mixed air
temperature is used for “preheat function”, issue a
“disable” request to “preheat function”.
f. Reset: An automatic reset occurs after mixed air temp.
input returns to within range continuously for 10 seconds.
Water Flow Fail
a. Data used (module,packet,byte,bit): WSM, 01,19, 05
b. Activation Conditions:Water flow input is detected open
1. at the end of precool water flow initiation state, or
2. continuously for five minutes while:
·water side economizer is open 100%,
· presetting of a head pressure valve, or
· demand for mechanical cooling.
Unit must be: a. configured with water cooled condenser
and/or water economizer and b. have water flow switch
installed.
c.Time to React: immediate
e. Actions to be Initiated: A “lockout all ckts” request is
issued to the “compressor staging function”
f. Reset: Automatic reset occurs after water flow input
returns to within range continuously for 3 seconds, water
pump is requested OFF, or water flow switch becomes not
installed.
Z
Zone Cool Setpoint Failure
Problem: Occupied zone cooling setpoint is out of range.
Reason for Diagnostic: Input designated as occupied zone
cooling setpoint source is out of range (temp. < 45°F or >
94°F).
UCM Reaction:The active occupied zone cooling setpoint
reverts to the default occupied zone cooling setpoint.
Reset Required: (PAR) an automatic reset occurs after
designated occupied zone CSP input returns to its
allowable range for 10 continuous seconds, or after a
different valid occupied zone CSP selection source is user-
defined.