Maritime Geothermal ATF-45, Инструкция по установке и обслуживанию

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Page 62 002000MAN-01 1-Jun-2018
OPERATION TROUBLESHOOTING - WATER HEATING MODE
Fault Possible Cause Verification Recommended Action
High or low suc-
tion or discharge
pressure
Faulty sensor Compare pressure sensor reading
against a known reference such as a
new refrigeration manifold set.
Check wiring, replace sensor. If
problem persists, replace control
board.
High discharge
pressure
Low indoor loop flow rate. Verify that indoor delta T is 8-12°F
(4-7°C)
Increase flow rate if new installa-
tion, check for fouled heat ex-
changer if existing installation.
Temperature setpoint(s)
too high (if using external
aquastat or BACnet con-
trol)
Use PC APP to verify that Indoor
OUT does not exceed 120°F (49°C)
Reduce setpoint(s).
EEV stuck almost closed
or partially blocked by for-
eign object.
Manually adjusting the EEV does not
affect the superheat or the suction
pressure. Low superheat and dis-
charge pressure.
Go to EEV troubleshooting sec-
tion.
Filter-dryer plugged Feel each end of the filter-dryer; they
should be the same temperature. If
there is a temperature difference then
it is plugged. Also causes low suc-
tion pressure.
Replace filter-dryer.
Unit is overcharged. High subcooling, low Indoor Loop
delta T.
Remove 1/2 lb of refrigerant at a
time and verify that the discharge
pressure reduces.
Low suction
pressure
Indoor OUT temperature
too cold (on startup or if
unit has been off for ex-
tended period)
Ensure Indoor OUT temperature is
above the low limit indicated in the
Model Specific Information sec-
tion.
Reduce flow temporarily until In-
door Out temperature has risen
sufficiently.
Low or no outdoor unit
airflow
Visually check fan to see if it is oper-
ating.
Go to Outdoor Fan Troubleshoot-
ing section.
TS1 temperature sensor
not reading properly.
If the sensor is reading low it will
cause the superheat to appear high,
which causes the EEV to continually
close.
Verify EEV position is low com-
pared to normal. Check tempera-
ture sensor, replace if necessary.
Filter-dryer plugged Feel each end of the filter-dryer; they
should be the same temperature. If
there is a temperature difference then
it is plugged. Also causes low suc-
tion pressure.
Replace filter-dryer.
EEV stuck almost closed
or partially blocked by for-
eign object.
Manually adjusting the EEV does not
affect the superheat or the suction
pressure. Low superheat and dis-
charge pressure.
Go to EEV troubleshooting sec-
tion.
Low refrigerant charge. Superheat is high, EEV position is
high.
Locate the leak and repair it.
Spray Nine, a sniffer, and/or dye
are common methods of locating
a leak.