Carrier 16DF013-050 - Manual (Page 44)

Normal Shutdown Procedure (Fig. 25) — De-
press the Stop button on the control panel. The operation
status indictor will show ‘‘dPP’’ on cooling and ‘‘dPO’’ on
heating during the machine shutdown cycle. The burner con-
trol will move to the LOW FIRE position and the burner
combustion will then be shut off. After approximately 15 min-
utes of automatic dilution, the machine will shut down and
the status indicator will show ‘‘000’’.
Do not stop the cooling/heating load or pumps during the
dilution cycle. During this period the machine will have re-
sidual cooling or heating effect which must be dissipated by
the load. Stopping the chilled water pump or cooling load
during the cooling dilution cycle could cause freeze damage
to the evaporator tubes.
Close the main fuel supply valve when burner combus-
tion has stopped. Open the main circuit breaker (MCB) in
the control panel when (but not until) the dilution cycle has
stopped (status indicator shows ‘‘000’’). Leave the direct cur-
rent power switch (TS1) ON to keep the circuit board pow-
ered. If the chilled/hot water pump, cooling water pump, and/or
cooling tower fan are not interlocked with the chiller/heater
controls, stop them when the first character on the status in-
dictor shows ‘‘0’’.
NOTE: When the machine is stopped by automatic Start-
Stop operation, leave the main fuel valve open, the panel
main disconnect switch open, and the pumps and cooling
tower in the ready-to-run state so the machine will be ready
for automatic restart. The status indicator will show ‘‘APO’’.
Fig. 32 — Normal Operation Flow Chart
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