IDC2 EVAPORATIVE CONDENSERS
MAINTENANCE
140.940-IOM (DEC 13)
Page 13
MAINTENANCE
COLD WATER BASIN
The refrigerant to be condensed is circulated inside the tubes of
the unit’s heat exchanger. Heat flows from the refrigerant through
the coil to the spray water outside which is cascading over the
tubes. The spray water collects in the cold water basin, passes
the suction strainer and is pumped back to the distribution sys-
tem. The cold water basin is constructed from galvanized steel.
Water Levels
Model Number
At Overflow
Level (in.)
At Operating
Level (in.)
AllIDC2modelsexcept
IDC2-x-1218-x
11¾”
9”
IDC2-x-1218-x
13½”
10½”
Table 2 - Cold Water Basin Water Levels
•
The makeup valve controls the operating level, which is
maintained at the levels shown in
Table 2
.
•
The operating water level in the cold water basin will vary
with system thermal load (evaporation rate), the bleed rate
employed, and the makeup water supply pressure.
•
Check the operating water level monthly, and readjust the
float when necessary to maintain the recommended operat-
ing level.
Inspection & Maintenance
WARNING
Openings and/or submerged obstructions may exist in the
bottom of the cold water basin. Use caution when walking
inside the equipment.
•
Inspect the cold water basin regularly. Remove trash or debris
accumulated in the basin or on the strainer.
•
Quarterly or more often if necessary, drain, clean, and flush
the entire cold water basin with fresh water. This will remove
the sediment, which can collect in the basin during operation.
If not removed, sediment can become corrosive and cause
deterioration of the protective finish of metallic basins.
•
When flushing the basin, leave the strainer in place to prevent
the sediment from re-entering the system.
•
Remove the strainer after the basin has been flushed.
•
Clean and replace the strainer before refilling the basin with
fresh water.
•
Adjust the float to maintain the design operating level. See
Table 1
.
FAN
The IDC2 Evaporative Condenser uses axial fan(s). Thoroughly
inspect the fan for damaged or deteriorated fan blades and
replace the fan as required.
Inspection & Maintenance
•
If the unit is already in operation, while the fan is running,
check for any unusual noise or vibration.
•
With the fan off and the motor locked out and tagged, check
the general condition of the fan:
- Inspect for any loose or missing bolts in the fan shaft
bushing, the fan hub, and the fan shaft bearing(s).
- Check the fan blades for looseness, first by twisting the
blade by hand, and then by moving the blade tip up and
down. There should be no play or slippage.
- Inspect each blade for excessive scale build-up that could
cause vibration.
- Check each blade in the area of the shank for any signs
of cracking. If cracking is found, the fan motor should be
locked out immediately. Contact Johnson Controls-Frick
or your local Frick Factor for assistance.
•
Tip Clearance
: Check the clearance between the tip of the
blade and the fan cowl. The clearance should be between
1/8” and 1/2”.
•
Drain Holes
: On hollow blades, the drain hole in the blade
tip should be unobstructed. Tip: Use a piece of wire to probe
the hole.
•
Blade Pitch
: Check to ensure that the blades are all at the
same pitch. If uncertain, measure the pitch with an inclinom-
eter. All blades should be /-1/2°.
•
Rotation
: Turn the fan by hand to ensure that it moves freely
with no rough spots, binding or other malfunctions that could
cause vibration or fan motor overload. While rotating the
fan, check the blade tracking. All blades should track within
a 1/2” band at any single point around the cowl.
•
Direction of Rotation
: On initial start-up, or if the fan motor
has been rewired, bump the fan motor and note the direction
of rotation. It should rotate in the direction indicated by the
arrow on the fan cowl.
•
Operation
: On initial start-up, run the fan in the manual
position for several minutes and check for any unusual noises
or vibration.
FAN DRIVE SYSTEM
Fortitude™ Power Train
The Fortitude™ Power Train consists of a solid-backed, multi-
groove, neoprene/polyester belt rated for evaporative condenser
service, and corrosion-resistant sheaves. These components
provide high reliability with low maintenance requirements.
Inspection & Maintenance
Fortitude™
Power Train requires a periodic check of the belt
condition and, when necessary, tension adjustment. The recom-
mended service intervals are as follows:
• Initial Start-Up
:
- No servicing is required prior to initial start-up since
the drive has been tensioned and aligned at the factory.
[IDC2-x-1212-x and IDC2-x-1218-x]
