610.020-IOM (NOV 19)
Page 10
EVAPORATOR AND AIR COOLER
INSTALLATION - OPERATION - MAINTENANCE
The heater rods for the drain pan section are attached
to the underside of the heater sheet which is positioned
below the coil and held in place with clips. All wiring for
heater rods is terminated within a junction box located on
the end tube sheet of the unit.
Wattages for heater elements depend on the room tem-
perature. Check carefully at the time of selection. See
Table 6.
WARNING
Before performing any service work on the equipment,
particularly in the vicinity of the fans or any other mov-
ing part, ensure that the correct electrical precautions
are adhered to. All electrical switchgear for the fans
must be disconnected, locked out and tagged out.
WATER DEFROST
For water defrost to function correctly it is essential that
an adequate supply of suitably warm water (> 55°F [13°C])
is available at the job site. The defrost method consists
of the water being evenly distributed over the coil from a
water distribution pan positioned on top of the coil. Water
flow is required until all frost has been melted off the
finned surface.
Control the flow rate by regulating a balancing valve,
located at the inlet to each unit. See Table 7 for water
flow pipe sizing. Adjust the flow to ensure full coverage of
the coil plan area and take care not to allow the water dis-
tribution pan to overflow. Flow rate requirements for each
unit are indicated on the submittal drawings. During the
setup and commissioning, the defrost operation must be
carefully observed to ensure that the entire coil is cleared
of frost. The time required to clear the coil can vary from 3
mins to 15 mins. Never exceed 15 mins. If this is the case,
there may be inadequate water supply or inlet tempera-
ture may be too low.
All water lines within refrigerated spaces must be insu-
lated and heat traced to prevent these lines freezing. Lines
must also be pitched up to 1/2 in. per linear ft to allow the
water to drain at the completion of the defrost period.
Large volumes of water also require adequately sized
condensate drain lines. See Table 8. Condensate drain lines
must have a minimum inclination of 1/2 in. per linear ft.
Sufficient fall from the drain pan outlet is required before
entering the trap. This enables the static head to over-
come the pressure drop of the water flow through the trap.
Always locate the traps outside the refrigerated space.
Condensate lines must be heat traced and insulated.
Transportation and rigging
PACKING INFORMATION
All FRICK air coolers are crated so they can be removed
from a truck with a forklift or a crane. When lifting any
unit with a forklift it is essential that the forks extend the
full span of the skid and do not make contact with any
portion of the unit.
Units are either plastic wrapped with a heavy duty plastic
wrap and positioned on a skid or have wood crating
around and on top of the unit, also placed on a skid.
When using a crane to lift the unit, use only the desig-
nated lifting points as detailed on the rigging drawing
attached to the unit at the time of shipping. Always ensure
that the lifting points are balanced and evenly spread.
NOTICE
Never lift unit by placing forks in direct contact with
the lower portion of the unit or the drain pan.
Table 7:
Pressure and diameter
Pressure
drop,
psi/100
Pipe diameter, in.
1
1 1/4
1 1/2
2
2 1/2
3
4
5
2
8
17
23
50
89
144
307
553
5
13
26
38
81
146
236
504
906
10
19
28
56
118
213
344
733
1318
15
24
49
69
147
265
428
912
1640
20
28
56
81
172
309
500
1065
1916
30
35
70
101
214
385
622
1326
2385
40
40
81
117
250
450
727
1549
2786
Table 8:
Water flow rates for different pipe diameters
Flow rate from
drain pan (gpm)
15
17
23
50
89
144
307
Pipe diameter
(in.)
2
26
38
81
146
236
504