Functional Troubleshooting - Heat Controller HEV Series Installation, Operation & Maintenance Manual

Installation, Operation & Maintenance
Fault Htg Clg Possible Cause
Main Power Problems
X
HPWS
X
X
X
X
X
LP/LOC Fault-Code 3
Low Pressure/Loss of Charge X
X
LT1 Fault - Code 4
X
Water Low Temperature
X
X
X
LT2 Fault - Code 5
X
X
X
Condensate Fault-Code 6
X
X
X
Over/Under Voltage-Code 7
(Auto Resetting)
X
X
Unit Performance
Sentinel-Code 8
Swapped Thermistor
X
Code 9
X
ECM Fault - Code 10
Low Air Coil Pressure Fault
(ClimaDry) Code 11
Low Air Coil Temperature
Fault - (ClimaDry) Code 12
HEV/H SERIES

FUNCTIONAL TROUBLESHOOTING

Solution
Check Line Voltage circuit breaker and disconnect
Check for line voltage between L1 and L2 on the contactor
X Green status LED off
Check for 24VAC between R and C on DXM
Check primary/secondary voltage on transformer
X Reduced or no water flow Check pump operation or valve operation/setting
in cooling
Check water flow adjust to proper flow rate
X
Water t emperature out of range in
Bring water temp within design parameters
cooling
Check for dirty air filter and clean or replace
Check fan motor operation and airflow restrictions
Reduced or no air flow
Dirty air coil- construction dust etc.
in heating
Too high of external static. Check static vs blower table
Air t emperature out of range in
Bring return air temp within design parameters
heating
Check superheat/subcooling vs typical operating condition
X Overcharged with refrigerant
table
X
Bad HP switch Check switch continuity and operation - Replace
X Insufficient charge Check for refrigerant leaks
Compressor pump down at start-
Check charge and start-up water flow
up
Check pump operation or water valve operation/setting
Reduced or no water flow
Plugged strainer or filter - clean or replace
in heating
Check water flow adjust to proper flow rate
Inadequate anti-freeze level Check antifreeze density with hydrometer
Improper low temperature setting
Clip LT1 jumper for antifreeze (10°F) use
(30°F vs 10°F)
Water t emperature out of range
Bring water temp within design parameters
X Bad thermistor Check temp and impedance correlation per chart
Check for dirty air filter and clean or replace
Reduced or no air flow
Check fan motor operation and airflow restrictions
X
in cooling
Too high of external static - check static vs blower table
Too much cold vent air - bring entering air temp within
X Air temperature out of range
design parameters
Improper low temperature setting
X Normal airside applications will require 30°F only
(30°F vs 10°F)
X Bad thermistor Check temp and impedance correlation per chart
X Blocked drain Check for blockage and clean drain
X Improper trap Check trap dimensions and location ahead of vent
Check for piping slope away from unit
X Poor drainage Check slope of unit toward outlet
Poor venting - check vent location
X Moisture on sensor Check for moisture shorting to air coil
Plugged air filter Replace air filter
X
Find and eliminate rectriction - increase return duct
X Restricted return air flow
and/or grille size
Check power supply and 24VAC voltage before and during
operation
Check power supply wire size
X Under voltage
Check compressor starting. Need hard start kit?
Check 24VAC and unit transformer tap for correct power
supply voltage
Check power supply voltage and 24VAC before and during
operation.
X Over voltage
Check 24VAC and unit transformer tap for correct power
supply voltage
Heating Mode LT2>125°F Check for poor air flow or overcharged unit
Cooling Mode LT1>125°F OR
X Check for poor water flow, or air flow
LT2< 40°F
X LT1 and LT2 swapped Reverse position of thermistors
Check blower line voltage
X Blower does not operate
Check blower low voltage wiring
Blower operating with incorrect Wrong unit size selection
airflow
Wrong unit family selection
Wrong motor size
Incorrect blower selection
Check for dirty air filter and clean or replace
X Reduced or no air flow in cooling
Check fan motor operation and airflow restrictions
or ClimaDry
Too high of external static - check static vs blower table
Too much cold vent air - bring entering air temp within
Air temperature out of range
design parameters
Bad pressure switch Check switch continuity and operation - replace
Check for dirty air filter and clean or replace
X Reduced airflow in cooling,
Check fan motor operation and airflow restrictions
ClimaDry, or constant fan
Too high of external static - check static vs blower table
Too much cold vent air - bring entering air temp within
Air temperature out of range
design parameters
Bad thermistor Check temp and impedance correlation per chart
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Heat Controller, Inc.