18
FORM CIM 0203
9. Calculate the volume of de-scaler required:
Water Quantity = 1/2 Total Gallons = ____ Gallons
De-Scaler Quantity = 1/2 Total Gallons =____ Gallons
10. Make sure pump is primed.
11. Circulate the required quantity until fluid char-
acteristics indicate that de-scaling process is
complete. Manufacturer’s instructions will
provide details on this.
12. Disconnect pump, hoses and tank from heat
exchanger.
13. Flush heat exchanger with water.
14. Return heat exchanger and system components
to service. Check all valves and fitting con-
nections.
15. Record performance values:
BEFORE
AFTER
Pressure Drop
_______ psig
_______ psig
Entering Temp.
_______°F
_______°F
Leaving Temp.
_______°F
_______°F
BLOWERS
Air-cooled units are provided with adjustable belt
drive blower packages for both the evaporator and
condensing sections. Check that the blower wheel
is tight on the shaft and does not contact the hous-
ing. Bearings are permanently sealed, but should
be checked periodically for signs of wear. Check
for restrictions or foreign material in the air circuit.
The drive may be adjusted for different static pres-
sures. If such an adjustment is made, check that the
motor current draw does not exceed the motor
nameplate current by more than 10%.
UNIT
EVAPORATOR
CONDENSER
CFM
CFM
1 Ton
400
700
1-1/2 Ton
600
850
2 Ton
800
1600
3 Ton
1200
2000
4 Ton
1600
2500
5 Ton
2000
3300
6 Ton
2400
3800
8 Ton
3200
4250
10 Ton
4000
6000
12 Ton
4800
6000
15 Ton
6000
7500
Figure 20:
Fan Capacities
On units with three-phase fan motors, check
for proper blower rotation at start-up. If they
run backwards, interchange two of the in-
coming power leads.
BLOWER MOTORS
All blower motors are equipped with thermal over-
load protectors.
CAUTION: Open disconnects to unit, as mo-
tor will start when automatic thermal over-
load resets.
BLOWER SPEED ADJUSTMENT
Blower speed may be changed by adjusting the vari-
able diameter sheave provided on the blower drive
motor. Sheave may be adjusted by removing the
belt and loosening the setscrew located in the hub
of the outer flange. With the setscrew loosened, the
flange may be turned clockwise to increase blower
speed and counter-clockwise to reduce blower
speed.
CAUTION: Setscrew must be positioned di-
rectly above a flat section of the threaded
sheave shaft before tightening to hold adjust-
ment.
CAUTION: Reduction of airflow through
excessive external air friction losses, lowered
blower speed operation with dirty filters, or
obstructed air flow may result in excessive
condensation at air outlets, short cycling, or
total unit shutdown due to evaporator coil
icing.
NOTE: Verify that the motor current draw
does not exceed the motor nameplate cur-
rent by more than 10%.
BLOWER MOTOR LUBRICA
BLOWER MOTOR LUBRICA
BLOWER MOTOR LUBRICA
BLOWER MOTOR LUBRICA
BLOWER MOTOR LUBRICATION
TION
TION
TION
TION
Motor manufacturers indicate that motors never need
relubrication, but if units run continuously, it is rec-
ommend that they be re-lubricated every 5500 hours
(7-8 months). If unit motors are run in a cyclical
manner, lubrication is recommended every 5 years.
Summary of Contents for 4CA1901
Page 2: ...2 FORM CIM 0203 ...
