Troubleshooting - Greenheck HRE-20 Installation, operationand Maintenance Manual

TROUBLESHOOTING FOR EVAPORATIVE MODULE
Symptom
Insufficient water
volume or recirculation
pump not operating
Irregular water
distribution on cooling
media
Scale and mineral
deposit formation on
face of media
Water Carry-Over
Inadequate cooling
Excessive water
discharge into drain
Poor performance
after cooling pad
replacement
Solution
A . Check water level in base pan . The
level should be at 1 inch .
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 .
D . Clogged or worn out pump .
E . Clogged header .
F . Water flow adjustment device
Water distribution header, orifices or media partially blocked or plugged .
Remove evaporative cooler from unit .
Disassemble and clean distribution header, orifices and media .
A . Increase bleed rate .
B . Increase water flow rate . Media is self-cleaning with flow rate of
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 . Check water flow across the face of the media . Irregular water distribution
must be corrected (see above)
D . 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 550 fpm . Decrease fan rpm and airflow .
C . Localized face velocities exceeding 550 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 airflow .
C . Check outside wet-bulb temperature . High wet-bulb temperatures can
decrease performance .
D . Check water flow rate over media . Flow rate should be
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 1 inch .
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 .
/
1
1
2
Entering Air
C
Header
Detail
/ to 2
1
1
2
to 2 gpm per
°
45
Leaving Air
°
15
15