Evaporative Cooling - Greenheck ERCH-20 Installation, Operation And Maintenance Manual

Troubleshooting – Evaporative Cooling
Symptom Possible Cause
Water level in sump pan too low.
Pump filter clogged.
Pump not getting power.
Insufficient water
volume or recirculation
pump not operating
Clogged header.
Water flow adjustment device improperly set. Check water flow adjustment clamp for proper setting.
Irregular water
Clogged header.
distribution on cooling
media
Water flow adjustment device improperly set. Check water flow adjustment clamp for proper setting.
Water mineral concentration too high.
Water flow rate too low.
Scale and mineral
deposit formation on
face of media
Header partially clogged.
Poor quality supply water.
Header partially clogged.
Unit moving too much air volume.
Water Carryover
Non-uniform airflow across entering media
face.
Sump overflow drain not operating.
Header partially clogged.
Unit moving too much air volume.
Inadequate cooling
Poor weather conditions for application.
Water flow rate too low.
Bleeder valve improperly adjusted.
Excessive water
discharge into drain
Water level in sump pan too low.
®
Corrective Action
Check water level in sump pan. Water level should be
maintained at greater than one inch.
Check the pump filter at the inlet. Clean the filter if
clogged or dirty.
If pump is not operating, check wiring for loose
connections and proper voltage.
Remove media from unit
and remove media cover
to visually inspect header
assembly. Clear holes
with drill if necessary.
Water distribution header, orifices or media partially
blocked or plugged.
Increase bleed rate.
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.
Check water flow across the face of the media. Irregular
water distribution must be corrected (see above).
If this condition persists, chemicals may need to be
added. Water pH should be maintained between
6 and 8.
Irregular water distribution on face of media (see above).
Average face velocity exceeds 550 fpm. Decrease fan
rpm and airflow.
Localized face velocities exceeding 550 fpm. Air filters
or media face area is partially blocked. Clean or replace
air filters and media.
Check the overflow for blockage.
Irregular water distribution over face of media (see
above).
Average face velocity exceeds 550 fpm. Decrease fan
rpm and airflow.
Check outside wet-bulb temperature. High wet-bulb
temperatures can decrease performance.
Check water flow rate over media. Flow rate should be
1-1/2 to 2 gpm per square foot of media top area.
Check the water bleed off rate and make sure that it is
not excessive.
Check water level in sump pan. The level should be at
one inch.
Energy Recovery Ventilator with Heating and Cooling General Description - NOT model specific
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