Trane 5TXCA001AS3HCA - Troubleshooting Indoor TXV; Cooling Mode

18-AD47D1-1B-EN 21
Installer’s Guide
X: TROUBLESHOOTING:
Is sub coolingatthe
outdoor unit between
8to12F?
Troubleshooting IndoorTXV /CoolingMode
NO
YES
Is superheat
<5F?
YES
Correctair
flow
problem
Is airflow at least
350CFM per ton?
YES
NO
Remove sensing bulbfrom the
suctionline. Measuresuperheat
at indoor coil while holding the
bulb in bare hand forone minute.
Does superheat decrease?
Measure superheat at indoor coil
whileplacing thebulb in an ice
and waterbathfor one minute.
Does superheat increase?
YES
Replacethe
TXV
TXVisOK
NO
Is superheat
<25F?
YES
NO
Is indoor
temperature more
than 85F?
NO
Is subcoolingless
than 8F?
YES
Confirmthat charge
is correct andlook
fordirty or restricted
outdoor coil.
Confirmthat
chargeis
correct.
NO
Beforestarting,insurethe
blowerwheel,indoor and outdoor
coils areclean.
Is theliquidline
temperature at indoor
coil within8Fof outdoor
liquid line temperature?
YES
Verify line setis
sizedproperly
forapplication
NO
Thesystemisrunning at max
capacityand this maybe
causingthe Highsuperheat.
Wait until indoor temperature
is less than 80F and check
superheat again.
YES
YES
Verify Inlet screen
of inlettube
assembly is clear
of debris
NO
VerifyInlet screen
of inlet tube
assembly is clear
of debris
NO