Carrier 50YFV Installation, Operation And Maintenance Instructions page 56

R e s i d e n t i a l D i g i t a l P a c k a g e d U n i t s G T- P B S e r i e s - 6 0 H z P u r o n
R e v : 4 A p r i l , 1 4
Performance Troubleshooting
Symptom
Insufficient Capacity/
Not Cooling or Heating
Properly
High Head Pressure
Low Suction Pressure
56
Htg Clg Possible Cause
X X Dirty filter
Rduced or no air flow
X
in heating
Reduced or no air flow
X
in cooling
X X Leaky duct work
X X Low refrigerant charge
X X Restricted metering device
X Defective reversing va lve
X X Thermostat improperly located
X X Unit undersized
X X Scaling in water heat exchanger
X X Inlet water too hot or cold
Reduced or no air flow
X
in heating
X Reduced or no water flow
in cooling
X Inlet w ater too hot
Air temperature out of range in
X
heating
X Scaling in water heat exchanger
X X Unit over charged
X X Non-condensables insystem
X X Restricted metering device
Reduced water flow
X
in heating
X Water temperature out of range
Reduced air flow
X
in cooling
X Air temperature out of range
X X Insufficient charge
Solution
Replace or clean
Check for dirty air filter and clean or replace
Check fan motor operation and airflow restrictions
Too high of external static - check static vs blower table
Check for dirty air filter and clean or replace
Check fan motor operation and airflow restrictions
Too high of external static - check static vs blower table
Check supply and return air temperatures at the unit and at
distant duct registers if significantly different, duct leaks
are present
Check superheat and subcooling per chart
Check superheat and subcooling per chart - replace
Perform RV touch test
Check location and for air drafts behind stat
Recheck loads & sizing check sensible clg load and heat
pump capacity
Perform Scaling check and clean if necessary
Check load, loop sizing, loop backfill, ground moisture
Check for dirty air filter and clean or replace
Check fan motor operation and airflow restrictions
Too high of external static - check static vs blower table
Check pump operation or valve operation/setting
Check water flow adjust to proper flow rate
Check load, loop sizing, loop backfill, ground moisture
Bring return air temp within design parameters
Perform Scaling check and clean if necessary
Check superheat and subcooling - reweigh in charge
Vacuum system and reweigh in charge
Check superheat and subcooling per chart - replace
Check pump operation or water valve operation/setting
Plugged strainer or filter - clean or replace
Check water flow adjust to proper flow rate
Bring water temp within design parameters
Check for dirty air filter and clean or replace
Check fan motor operation and airflow restrictions
Too high of external static - check static vs blower table
Too much cold vent air - bring entering air temp within
design parameters
Check for refrigerant leaks
®