American Dream Ultra Performance Geothermal Copper Series, Installation And Service Manual

Page: 38 / 60

Page 38 000744MAN-02 25 MAY 2009
FAN TROUBLESHOOTING
Fault Possible Cause Verification Recommended Action
Low Airflow
Dirty air filter Inspect. Replace.
Dirty air coil. Inspect. Clean.
Poor Ductwork Measure delta T between supply
and return ducts at the unit, it in
heating mode, it should not be
above 30°F(17°C). The ECM fan will provide proper
airflow up to 0.5 inH2o for 1/2HP
motors and 0.7 inH2o for 1HP
motors. The ductwork is poorly
designed or greatly undersized if
the fan motor cannot provide the
required airflow.
Air flow selected on Tap
Board is too low. Check selection on Air Flow Tap
Board. Select a higher setting.
Air flow reduction is en-
abled. AR1 and AR2 are connected with a
dry contact. Air flow reduction may not be fea-
sible with poor ductwork, and/or
lower Air Flow selections. In-
crease settings until unit operates
properly.
Fan operating on
wrong Stage
speed Fan Control Signal Har-
ness is loose. Verify that the connector is properly
inserted into the fan motor. Gently
tug on each wire to verify it is prop-
erly inserted into the connector. Repair any loose connections.
Faulty Control Signal Har-
ness or faulty motor
head. Measure 24VAC between White (pin
3) and the following at the fan con-
trol signal harness (insert probes in
connector where wire is inserted, do
not unplug the connector):
Circulation = Grey (pin 15)
Stage 1 = Yellow (pin 6)
Stage 2=Yellow/Black (pin14)
Stage 3 = Violet (pin 2) If proper signal isn’t present, re-
place Fan Control Signal Har-
ness. If proper signal is present,
replace fan motor head.
Fan not operat-
ing or operating
intermittently Fan Control Signal Har-
ness and/or Fan Power
Harness is loose. Verify that the connector is properly
inserted into the fan motor. Gently
tug on each wire to verify it is prop-
erly inserted into the connector. Repair any loose connections.
Faulty Control Signal Har-
ness or;
Faulty motor head. Measure 24VAC between White (pin
3) and the following at the fan con-
trol signal harness (insert probes in
connector where wire is inserted, do
not unplug the connector):
Circulation = Grey (pin 15)
Stage 1 = Yellow (pin 6)
Stage 2=Yellow/Black (pin14)
Stage 3 = Violet (pin 2) If proper signal isn’t present, re-
place Fan Control Signal Har-
ness. If proper signal is present,
replace fan motor head.
Fan Power Harness faulty
or;
Faulty motor. Insert the tips of the voltmeter
probes into the back of the connec-
tor at the fan to measure the voltage
across the red and black wires,
value should be 230VAC Replace Power Harness if
230VAC is not present, replace
motor if 230VAC is present