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