2. Turn the fan by hand to ensure rotation without obstruction. Remove obstruction, if present.
3. Start the pump(s) and check for the proper rotation as indicated by the arrow on the pump cover. If rotation is
wrong, stop pump and correct electrical wiring.
4. Start the fan(s) and check for proper rotation as indicated by the arrow on the fan housing. If rotation is wrong
stop fan(s) and contact BAC.
Forward curved centrifugal fan
MOTOR VOLTAGE AND CURRENT
Check the voltage and the current of all three legs of the fan and pump motors. The current should not exceed the
nameplate rating. After prolonged shut-down (or motor is stored with unit in kit form) the motor insulation should be
checked with a Megger insulation tester prior to restarting.
1. Insulation resistance test – minimum value should be 1 Mega Ohm (1.000.000 Ohms).
2. Thermistors, if fitted, should be checked for continuity with a multi-meter but never Megger-tested.
3. Ensure supply voltage and frequency correspond to the motor nameplate rating.
4. Ensure shaft turns freely.
5. Wire the motor in accordance with the wiring diagram as shown on the motor nameplate and/or in the motor
terminal box.
6. Turn on unit and check amp draw does not exceed nameplate rating.
If motor is stored, it should be in a clean, dry place & have the shaft rotated occasionally. Storage areas
should not be subject to vibration.
CAUTION
Rapid on-off cycling can cause the fan motor to overheat.
It is recommended that controls be set to allow a maximum of 6 on/off cycles per hour.
When two speed motors are used, the motor starter should include a 15 seconds time delay when switching from
high to low speed.
In case of fan cycling, used as a method of capacity control, care needs to be taken when there are 2 fan motors
for one single upper section; both motors are operated or stopped simultaneously. This is the case for the following
models: VT1-1018-xxx, VT1-1218-xxx.
On all other models, fans can be switched on or off individually.
UNUSUAL NOISE AND VIBRATIONS
Unusual noise and/or vibration are the result of malfunctioning of mechanical components or operational problems
(e.g. unwanted ice formation). If this occurs, a thorough inspection of the entire unit followed by immediate
corrective action is needed. If required, consult your local BAC Balticare representative for assistance.
W W W . B A L T I M O R E A I R C O I L . E U
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5 Maintenance Procedure
5 Maintenance Procedure
