140.960-IOM (JUN 2016)
Page 46
IDCF & IDC3 EVAPORATIVE CONDENSERS
MAINTENANCE
WATER LEVEL CONTROL
There are two types of water level controls used on IDCF and
IDC3 units:
• Mechanical makeup valve assembly
• Optional electric water level control package
Mechanical Makeup Valve Assembly
A float-operated mechanical water makeup assembly is fur-
nished as standard equipment on the unit. The standard makeup
assembly consists of a corrosion resistant makeup valve con-
nected to a float arm assembly actuated by a polystyrene-filled
plastic float. The float is mounted on an all-thread rod held in
place by wing nuts. The water basin operating water level can
be adjusted by repositioning the float and all-thread rod using
the wing nuts provided.
NOTICE
If the unit has been ordered with the optional electric wa-
ter level control package or is intended for remote sump
application, a mechanical water makeup valve will not be
provided.
Inspection and Maintenance
• Inspect the make-up valve assembly monthly and adjust if
necessary.
• Inspect the valve annually for leakage. Replace the valve
seat if necessary.
• Maintain the make-up water supply pressure between 15
psig and 50 psig for proper operation. A pressure regulator
valve (provided by others) is recommended for pressures
over 50 psig.
• Set the initial basin water level by adjusting the wing nuts,
so that the make-up valve is completely closed when the
water level in the water basin is at the operating level as
stated in Table 3.
• If the thermal load is less than the design load at the time
of unit start-up, the procedure may produce operating
levels greater than those shown in Table 3. If operating
levels are higher than specified, readjust the float in order
to attain the recommended operating level.
• Closely monitor the water level in the water basin and
adjust the level if necessary during the first 24 hours of
operation.
• Operating at the recommended water level will ensure that
the unit basin contains sufficient water volume to prevent
air entrainment in the circulating pump during system
start-up and provides sufficient excess basin capacity to
accept the total system pull-down volume.
Optional Electric Water Level Control Package
As an option, an electric water level control package is avail-
able in lieu of the mechanical makeup assembly. The package
consists of a probe-type liquid level control assembly and a
slow-closing solenoid valve. Stainless steel electrodes, factory-
set at predetermined lengths, extend from an electrode holder
into the water basin.
Inspection and Maintenance
• Clean the stainless steel electrodes periodically to prevent
accumulations of scale, corrosion, sludge or biological
growth, which could interfere with the electrical circuit.
• The water level is maintained at the recommended
operating level regardless of the system thermal load.
Therefore, it is not recommended that the operating level
be adjusted.
• During the start-up of units equipped with the electric
water level control package, bypass the control unit in
order to fill the unit to the overflow connection.
LED Status Codes
•
LED on steady
: Indicates normal operation.
•
Steady one second flashing:
Indicates dirty probes,
reading in the capacitance mode. The unit will still operate
but will give the following status code of 1 second on, 1
second off (steady 1 second flashing). This status code
continues until the probes are cleaned and the power has
been reset. Note: No other status codes will be displayed
until the dirty probes are cleaned.
•
Two flashes and off for 5 seconds:
Indicates make-up
valve ran for more than 1 hour. The unit will continue to fill,
with the following status code of 1 second on, 1 second off,
1 second on and then off for 5 seconds before repeating.
This status will continue until power has been reset.
Possible causes: leaking tank, obstructed fill / defective
valve or reduced flow rate.
•
Three flashes and off for 5 seconds:
Indicates shorted
probes or highly conductive water. The unit will continue
to operate but will give the following status code of 1
second on, 1 second off, 1 second on, 1 second off, 1
second on and then off for 5 seconds before repeating.
This status will continue until the water is diluted or the
short is removed from the probes and power is reset.
•
Four flashes and off for 5 seconds:
Indicates black
probe (P6) reads covered, but white probe (P5) does not
read covered (white should also be covered because it
is longer than the black). This will cause the fill solenoid
valve to short cycle and lead to premature failure of the
fill valve. The unit will short cycle and give the status code
of 1 second on, 1 second off, 1 second on, 1 second off,
1 second on, 1 second off, 1 second on and then off for 5
seconds before repeating. The unit will continue to short
cycle until the condition has been corrected (clean white
probe) and the power reset.
•
LED does not come on after power up or resetting
power:
Indicates unit inoperative.
SYSTEM CLEANING
Coil Cleaning
Both the inside and outside of the heat exchange coil may require
occasional cleaning. The chemicals used must be compatible
with the materials being treated. For example, the standard coil
outside is galvanized steel. The inside of the coil is black carbon
steel. For finned coils, the coil cleaning must be careful not to
damage the fins (outside of the coils) and the coils themselves.
For specific recommendations on coil cleaning, contact a quali-
fied consultant.
