Digital Control Diagnosticsand Testmode - Friedrich PTAC Series Installation & Operation Manual

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Digital Control Diagnosticsand TestMode
Diagnostics
The Friedrich Smart Center continuously monitors the PTAC unit
operation and will store service codes if certain conditions are
witnessed. In some cases the unit may take action and shut the
unit off until conditions are corrected.
To access the error code menu press the 'Heat' and 'High Fan'
buttons simultaneously for three seconds. If error codes are
present they will be displayed. If multiple codes exist you can
toggle between messages using the temp A button. To clear
all codes press the temp v button for three seconds while in
the error code mode. To exit without changing codes press the
'Low Fan' button.
TestMode
For service and diagnostic use only, the built-in timers and
delays on the PTAC may be bypassed by pressing the 'Cool'
and 'Low Fan' buttons simultaneously for three seconds while
in any mode to enter the test mode. TEwill be displayed when
entering test mode, and DEwill be displayed when exiting. The
test mode will automatically be exited 30 minutes after entering it
or by pressing the 'Cool' and 'Low Fan' buttons simultaneously
for three seconds.
The chart below lists the possible error codes and their description:
Error
Code Translation Action Taken by Unit Possible Cause
Code
n., NOT USED NONE
UI
An extreme low voltage condition Shut down unit. Display Error code and flash. • Inadequate power supply
02 exists <198V for 230V units and Once voltage rises to normal level system power • Defective breaker
<239V for 265V units, is restored. • Blown fuse
03 Return air thermistor sensor open Set return air sensor = 75°F. Alternate flash set • Defective sensor
or short circuit point and error code. Leave unit running.
o,_I Indoor coil thermistor sensor open Set ID coil temp = 40°F. Alternate flash set point • Defective sensor
Or short circuit and error code. Leave unit running.
Outdoor coil thermistor sensor Set OD coil temp = 20°F. Alternate flash set point
n.g open Or short circuit and error code. Automatically change over to • Defective sensor
Electric heat Mode only. Leave unit running.
06
n"/
u/
IfO.D. coil Temperature > 175 Deg
F for 2 consecutive minutes. (Heat
Pump models only)
I.D coil temperature <30 Deg F for
2 consecutive minutes.
Alternate flash set point and error code. Shut unit
down for 5 minutes, then try again 2 times, if fails
the 3rd time, then shut down unit.
Alternate flash set point and error code. Continue
fan operation while the compressor is locked out
until the indoor coil thermistor reaches 45 ° F, and
then energize the compressor. However, com-
pressor must still wait a lockout time of 180 to 240
seconds.
• Dirty coil
• Fan motor failure
• Restricted air flow
• Non-condensables in
refrigeration system
• Dirty filters
• Dirty coil
• Fan motor failure
• Restricted airflow
• Improper refrigerant charge
• Restriction in refrigerant circuit
08 If unit cycles (Heat or Cool Alternate flash set point and error code. Keep unit • Unit oversized
demand)> 9 times per hour running. • Low load conditions
nS, If unit cycles (Heat or Cool Alternate flash set point and error code. Keep unit • Unit undersized
demand)< 3 times per hour running. • High load conditions
Alternate flash set point and error code. Keep unit • Room temperature fell below 40°F
.,n Room Freeze Protection triggered
u running.
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