Greenheck Fan HRE-20 - Manual (Page 9)

Symptom Solution
Leaving Air Entering Air
45 °
15 °
Insufficient water
volume or recirculation
pump not operating
Irregular water
distribution on cooling
media
Scale and mineral
deposit formation on
face of media
Excessive water
discharge into drain
Water Carry-Over
Poor performance after
cooling pad
replacement
Inadequate cooling
A. Check water level in base pan. The level should be at 2 inches.
B. Check the pump filter at the inlet. Clean the filter if clogged or dirty.
C. If pump is not operating, check wiring for loose connections and proper
voltage.
Water distribution header, orifices or media partially blocked or plugged.
Remove evaporative cooler from unit.
Disassemble and clean distribution header, orifices and media.
A. Check water flow across the face of the media. Irregular water distribution
must be corrected (see above)
B. Increase water flow rate. Media is self cleaning with flow rate of 1 1 ⁄
2
to 2
gpm per square foot of media top area. Generally this flow rate prevents
dissolved solvents from collecting on the media. To prevent further trouble,
flush and clean the system more frequently.
C. If this condition persists, chemicals may need to be added. Water pH
should be maintained between 6 and 8.
A. Irregular water distribution on face of media (see above).
B. Average face velocity exceeds 650 fpm. Decrease fan rpm and airflow.
C. Localized face velocities exceeding 650 fpm. Air filters or media face area
is partially blocked. Clean or replace air filters and media.
D. Check the overflow for blockage.
A. Irregular water distribution over face of media (see above).
B. Check for uniform air flow.
C. Check outside wet-bulb temperature. High wet-bulb temperatures can
decrease performance.
D. Check water flow rate over media. Flow rate should be 1 1 ⁄
2
to 2 gpm per
square foot of media top area.
A. Check the water bleed off rate and make sure that it is not excessive.
B. Check water level in base pan. The level should be at 2 inches.
Pad installed backwards. To get the
performance from the cooling pads,
they must be installed properly. The
pads are manufactured with 15/45
degree flute angles. The pads must
always be installed with the steeper
flute angle sloping down toward the
entering air side. See figure on right.
TROUBLE SHOOTING FOR EVAPORATIVE MODULE
9