Enertech WD240, Руководство по установке и эксплуатации, Страница: 25 / 32

25
IOM, WD Models Enertech Global
Section 10: Troubleshooting
A: Unit Will Not Start In Either Cycle
Thermostat
Set thermostat on heating and highest temperature setting. Unit should run. Set thermostat on
cooling and lowest temperature setting. Unit should run. Set fan to On position. Fan should run. If
unit does not run in any position, disconnect wires at heat pump terminal block and jump R, G, Y.
Unit should run in heating. If unit runs, replace thermostat with correct thermostat only.
Loose or broken
wires
Tighten or replace wires.
Blown Fuse/Tripped
Circuit Breakers
Check fuse size, replace fuse or reset circuit breaker.
Check low voltage circuit breaker.
Low Voltage Circuit
Check 24 volt transformer. If burned out or less than 24 volt, replace. Before replacing, verify tap
setting and correct if necessary.
Water Flow (runs for
30 sec)
If water flow is low (less than 3.5 GPM), unit will not start. Make sure Pump Module or solenoid
valve is connected (see wiring diagram). Water has to flow through the heat exchanger in the right
direction (see labels at water fitting connections) before the compressor can start. If water flow is
at normal flow, use an ohmmeter to check if you get continuity at the flow switch. If no switch is
open and flow is a normal flow, remove switch and check for stuck particles or bad switch.
B: Unit Running Normal, But Space Temperature Is Unstable
Thermostat
Thermostat is getting a draft of cold or warm air. Make sure that the wall or hole used to run
thermostat wire from the ceiling or basement is sealed, so no draft can come to the thermostat.
Faulty Thermostat (Replace).
C: No Water Flow
Pump Module
Make sure Pump Module is connected to the control box relay (check all electrical connections).
For non-pressurized systems, check water level in Pump Module. If full of water, check pump. Close
valve on the pump flanges and loosen pump. Take off pump and see if there is an obstruction in
the pump. If pump is defective, replace. For pressurized systems, check loop pressure. Repressurize
if necessary. May require re-flushing if there is air in the loop.
Solenoid valve Make sure solenoid valve is connected. Check solenoid. If defective, replace.
D: In Heating or Cooling Mode, Unit Output Is Low
Water Water flow & temperature insufficient.
Load Side Flow
Check speed setting, check nameplate or data manual for proper speed, and correct speed setting.
Check for dirty air filter—Clean or replace.
Restricted or leaky ductwork. Repair.
Refrigerant charge
Refrigerant charge low, causing inefficient operation. Make adjustments only after airflow and
water flow are checked.
Reversing valve
Defective reversing valve can create bypass of refrigerant to suction side of compressor. Switch
reversing valve to heating and cooling mode rapidly. If problem is not resolved, replace valve. Wrap
the valve with a wet cloth and direct the heat away from the valve. Excessive heat can damage the
valve. Always use dry nitrogen when brazing. Replace filter/drier any time the circuit is opened.
E: In Heating or Cooling Mode, Unit Output Is Low
Heat pump will not
cool but will heat.
Heat pump will not
heat but will cool.
Reversing valve does not shift. Check reversing valve wiring. If wired wrong, correct wiring. If
reversing valve is stuck, replace valve. Wrap the valve with a wet cloth and direct the heat away
from the valve. Excessive heat can damage the valve. Always use dry nitrogen when brazing.
Replace filter/drier any time the circuit is opened.
Water heat
exchanger
Check for high-pressure drop, or low temperature drop across the coil. It could be scaled. If scaled,
clean with condenser coil cleaner.
System undersized Recalculate conditioning load.
F: Water Heat Exchanger Freezes In Heating Mode
Water flow Low water flow. Increase flow. See F. No water flow.
Flow Switch Check switch. If defective, replace.
G: Excessive Head Pressure In Cooling Mode
Inadequate water
flow
Low water flow, increase flow.