Performance Troubleshooting - Heat Controller HP Series Installation, Operation & Maintenance Manual

Installation, Operation & Maintenance
Only Compressor Runs
Unit Doesn't Operate in
Cooling
Performance
Troubleshooting
Insufficient capacity/
Not cooling or heating
properly
High Head Pressure
Low Suction Pressure
Low discharge air
temperature in heating
High humidity
HP SerieS
FUNCTIONAL TROUBLESHOOTING
X X Thermostat wiring
X X Fan motor relay
X X Fan motor
X X Thermostat wiring
X Reversing Valve
X Thermostat setup
X Thermostat wiring
Thermostat wiring
X

PERFORMANCE TROUBLESHOOTING

Htg Clg Possible Cause
X X Dirty Filter
X Reduced or no Air flow
in heating
X Reduced or no Air flow
in cooling
X X Leaky duct work
X X Low refrigerant charge
X X Restricted metering device
X Defective Reversing Valve
X X Thermostat improperly located
X X Unit undersized
X X Scaling in water heat exchanger
X X Inlet Water too Hot or Cold
X Reduced or no Air flow
in heating
X Reduced or no water flow
in cooling
X Inlet Water too Hot
X
Air Temperature out of range in
heating
X Scaling in water heat exchanger
X X Unit Overcharged
X X Non-condensables insystem
X X Restricted metering device
X Reduced water flow
in heating
X Water Temperature out of range
X Reduced Air flow
in cooling
X Air Temperature out of range
X X Insufficient charge
X Too high of air flow
X Poor Performance
X Too high of air flow
X Unit oversized
Check G wiring at heat pump. Jumper G and R for fan
operation.
Jumper G and R for fan operation. Check for Line voltage
across BR contacts.
Check fan power enable relay operation (if present)
Check for line voltage at motor. Check capacitor
Check thermostat wiring at heat pump. Jumper Y and R for
compressor operation in test mode.
Set for cooling demand and check 24VAC on RV coil and at
CXM board.
If RV is stuck, run high pressure up by reducing water flow
and while operating engage and disengage RV coil voltage
to push valve.
Check for 'O' RV setup not 'B'
Check O wiring at heat pump. Jumper O and R for RV coil
'Click'.
Put thermostat in cooling mode. Check for 24VAC on O
(check between C and O); check for 24VAC on W (check
between W and C). There should be voltage on O, but not
on W. If voltage is present on W, thermostat may be bad
or wired incorrectly.
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
Check fan motor speed selection and airflow chart
See 'Insufficient Capacity'
Check fan motor speed selection and airflow chart
Recheck loads & sizing check sensible clg load and heat
pump capacity
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Heat Controller, Inc.
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