The
noise of the newly bought CL-450 is too loud that my wife complaint a lot.  So modification was took place.  The original fan was replaced by an
axial sleeve cooling fan, rated 0.4A at 220VAC.  The higher the ampere,
the higher the flow volume.  The
dimension of the fan is 172 x 150 x 51mm, the housing and blade are made of
aluminum.  The price is HK$100.

After
modification, the noise now is returned to an acceptable level.  Cooling time is increased from 30 mins to 40 mins for a 400L tank
with room temp. of 28C, setpoint 26C, all lights off.

First of all, remove the front filter cover and all the screws at
the bottom, the nuts at water connection, and the handles.

Remove
the connection for power (blue circle) and sensor (red circle) from the front,
then the case can be removed.  The
top box with silver insulation packing is the heat exchanger for water.

The
fan to be removed (blue circle) is mounted by two screws (red circle).  Be careful not to bend the capillary
tube too much on the other side when removing the screw.  Also, do not cut the wire now, as you
may want to discard all the changes later.
Leave it as the final procedure.

Now
we have to prepare the fan.  Note
the airflow direction indicated on fan body.  There are two wires (black in colour) from the fan for power, and a ground wire (not
included with fan) should be added as safety.

Now
we come to the most difficult and time consuming
part.  Cut the original fan stand
(blue line), revert it, drill hole and fit the new fan on it.  I cannot give the exact dimension as it is very much depend on the fan you buy.  You have to measure by yourself, and it
is the interest of DIY.  Pay
attention not to damage the condenser’s fin.  Mount the new fan onto the base.  Now you can cut the wires on the
original fan, and connect them to the new fan.

The
ground wire from the new fan should be connected to the ground of the
chiller.  You can connect it to the
condenser, and I chose the compressor’s box.  If you do not want to open this box, you
can connect outside by cut and connect to the ground wire (green in colour).

Check
all the wires again and the fan mount.  Test run the chiller
(fill the heat exchanger with water) and check if the fan is mounted
tightly.  Since the fan is a bit
smaller than the opening on condenser, the gap should be sealed to ensure the
flow of air.  You cannot get a bigger
fan as there is not enough space.

End