Water Make Up Valve; Pressurized Water Distribution Systems - EVAPCO ESW Series Operation And Maintenance Instruction

ADJUSTMENT
WINGNUTS
FLOAT ARM

Water Make Up Valve

MAKE-UP
FLOAT BALL
VALVE
A mechanical float valve assembly is provided as standard equipment on the
evaporative cooling unit (unless the unit has been ordered with an optional
electronic water level control package or the unit is arranged for remote
sump operation). The make up valve is easily accessible from outside the unit
through the access door or removable air inlet louver. The make up valve is a
bronze valve connected to a float arm assembly and is activated by a large
foam filled plastic float. The float is mounted on an all-thread rod held in
place by wing nuts. The water level in the basin is adjusted by repositioning
the float and all-thread using the wing nuts. Refer to Figure 15 for details. The
bottom center of the float should be set at 1" below the middle of the
overflow. At its highest point, float arm should be parallel to the water level.
The make up valve assembly should be inspected monthly and adjusted as
required. The valve should be inspected annually for leakage and if
Figure 15 – Mechanical Water Make Up Valve
necessary, the valve seat should be replaced. The make up water pressure for
the mechanical valve should be maintained between 20 and 50 PSIG.

Pressurized Water Distribution Systems

Check the water distribution system monthly to make sure it is operating properly. Always check the spray system with the pump on and
the fans off. On forced draft models, remove one or two eliminator sections from the top of the unit and observe the operation of the
water distribution system. On induced draft models, lifting handles are provided along the top layer of eliminators. Eliminators can be
easily removed from the access door and the distribution system observed. The diffusers are essentially non-clogging and should seldom
need cleaning or maintenance.
If the water diffusers are not functioning properly, it is a sign that the pan or system strainer has not been working properly and that foreign
matter or dirt has accumulated in the water distribution pipes. The nozzles can be cleared by taking a small pointed probe and moving it
rapidly back and forth in the diffuser opening.
If an extreme build-up of dirt or foreign matter occurs, remove the end cap in each branch to flush the debris from the header pipe. The
branches or header can be removed for cleaning, but do so only if necessary. Check the strainer in the pan to make sure it is in good
condition and positioned properly so that cavitation or air entrainment does not occur.
All Evaporative Condensers and Closed Circuit Coolers, except the ESWA/4 Closed Circuit Cooler, are supplied with ZMII ® spray
nozzles as standard. The ZMII ® spray nozzles do not need to be oriented a specific way to achieve proper coil coverage. Figure 16 shows
the standard orientation of the ZMII ® spray nozzles.
Figure 16 – ZMII ®
Spray Nozzle Orientation
All Coil Products except the ESWA/4
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