Heat Controller HTV Series - Performance Troubleshooting; Insufficient Capacity;Not Cooling or Heating Properly; Low Refrigerant Charge; Restricted metering device

HTV/HTD/HTH SERIES Heat Controller, Inc.
47
FUNCTIONAL TROUBLESHOOTING
Fault Htg Clg Possible Cause Solution
Set for cooling demand and check 24 VAC on RV
CXM board
X Reversing Valve
If RV is stuck, run high pressure up by reducing and
while operating engage and disengage RV to push
valve
X Thermostat Set-up Check for ‘O’ RV set-up not ‘B’
X Thermostat Wiring Check O wiring at heat pump. Jumper O and R
‘Click’
Unit Does Not Operate
in Cooling
X Thermostat Wiring Put thermostat in cooling mode. Check for 24 (check
between C and O); check for 24 VAC on W between W
and C). There should be voltage on W. If voltage is
present on W, thermostat or wired incorrectly
PERFORMANCE TROUBLESHOOTING
44
Performance
Troubleshooting
Htg Clg Possible Cause Solution
X X Dirty Filter Replace or clean
Check for dirty air filter and clean or replace
Check fan motor operation and airflow restriction
X Reduced or No Air Flow in Heating
Too high of external static. Check static valve
Check for dirty air filter and clean or replace
Check fan motor operation and airflow restriction
X Reduced or No Air Flow in Cooling
Too high of external static. Check static valve
X X Leaky Duct Work Check supply and return air temperatures at two
distant duct registers if significantly different ,
restrictions are present
X X Low Refrigerant Charge Check superheat and subcooling per chart
X X Restricted metering device Check superheat and subcooling per chart
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 vs.
heat pump capacity
X X Scaling in Water Heat Exchanger Perform scaling check and clean if necessary
Insufficient Capacity/
Not Cooling or Heating
Properly
X X Inlet Water Too Hot or Cold Check load, loop sizing, loop backfill, ground
Functional Troubleshooting
Performance Troubleshooting
FUNCTIONAL TROUBLESHOOTING
Fault Htg Clg Possible Cause Solution
Set for cooling demand and check 24 VAC on RV
CXM board
X Reversing Valve
If RV is stuck, run high pressure up by reducing and
while operating engage and disengage RV to push
valve
X Thermostat Set-up Check for ‘O’ RV set-up not ‘B’
X Thermostat Wiring Check O wiring at heat pump. Jumper O and R
‘Click’
Unit Does Not Operate
in Cooling
X Thermostat Wiring Put thermostat in cooling mode. Check for 24 (check
between C and O); check for 24 VAC on W between W
and C). There should be voltage on W. If voltage is
present on W, thermostat or wired incorrectly
PERFORMANCE TROUBLESHOOTING
44
Performance
Troubleshooting
Htg Clg Possible Cause Solution
X X Dirty Filter Replace or clean
Check for dirty air filter and clean or replace
Check fan motor operation and airflow restriction
X Reduced or No Air Flow in Heating
Too high of external static. Check static valve
Check for dirty air filter and clean or replace
Check fan motor operation and airflow restriction
X Reduced or No Air Flow in Cooling
Too high of external static. Check static valve
X X Leaky Duct Work Check supply and return air temperatures at two
distant duct registers if significantly different ,
restrictions are present
X X Low Refrigerant Charge Check superheat and subcooling per chart
X X Restricted metering device Check superheat and subcooling per chart
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 vs.
heat pump capacity
X X Scaling in Water Heat Exchanger Perform scaling check and clean if necessary
Insufficient Capacity/
Not Cooling or Heating
Properly
X X Inlet Water Too Hot or Cold Check load, loop sizing, loop backfill, ground