Greenheck Fan HEAT RECOVERY UNIT WITH EVAPORATIVE COOLING HRE-20 - Manual (Page 16)

16
Regularly scheduled maintenance is the key to peak
performance, minimized cost, and extended life of
the evaporative cooler . The following is a checklist of
items that need to be looked at on a regular basis .
1 . The media should be checked for mineral and
foreign material deposits that have built up . If
these items are left on the media, the life and
performance of the unit will be greatly reduced .
Also, there are risks of water carryover when
this type of condition exists . When signs of
mineral build-up are noticed, you should increase
the bleed off rate . If this does not solve the
problem, chemicals may need to be added to
the water . The evaporative pads tend to be self-
cleaning . Depending on water quality and system
maintenance, the useful life of the pads should
be 3 to 5 years .
2 . The media should be periodically brushed lightly
with a soft bristle brush in an up and down
motion (never brush side-to-side) while flushing
with water . This will also aid in reducing the
amount of foreign material build-up .
3 . The water should be shut off and all the lines
drained when the temperature drops below 50ºF .
4 . When the evaporative cooler is going to be used
for the first time each season, it is recommended
that the media be flushed with clean water for a
period of 2 minutes (see Evap Module Start-Up) .
5 . At the beginning of each cooling season, the
upright recirculating pump should have the
shaft oiled and spun to eliminate the potential of
seizing and pump burn out .
6 . If the cooling media was removed from the
unit, check to make sure that is not installed
backwards . If the media is installed backwards,
there will be large amounts of water carry
over downstream of the evaporative cooler .
Continuous operation in this manner may cause
serious damage and void the warranty .
7 . At the end of each cooling season the
evaporative cooler should be thoroughly
cleaned . A dispersant and biocide (consult water
treatment consultant for suitable materials and
dosage levels) should be recirculated for 12 to 24
hours prior to performing the following steps:
a) Disconnect power to unit .
b) Shut off all water to the unit
c) Open evaporative cooling section door
d) Flush distribution headers and media for 20
minutes
e) Turn off pumps and drain all water distribution
piping, headers, etc .
f) Dry media completely by running blowers .
g) Brush media as described in Paragraph 2 and
perform steps d and e again .
h) Clean all remaining components (i .e . sump,
pump, etc .) of any mineral deposits or foreign
materials
i) Replace all worn or non-functioning parts
j) Reassemble the cooling unit .
k) Close cooling section door .
l) Turn the main disconnect ‘ON’, leaving the
cooling switch in the ‘OFF’ position .
8 . If the evaporative cooler will be turned off during
the cooling season for an extended period of
time, it is recommended that the media be dried
out . This can be accomplished by allowing the
blowers to continue to run for 1-2 hours . Doing
so, will prevent organic build-up on the media
and subsequent odors getting into the space .
9 . Media should be permitted to dry once per week
by allowing the blowers to run for 1-2 hours .
10 . A flush cycle should be performed weekly for one
hour with the fans off .
To remove media, disconnect water line to evap
header as shown below . Then slide media section
out of unit . Sump will remain in unit . If media is wet,
turn off water supply, then turn on unit and allow air
to flow thru media for 10 -20 minutes . This will dry the
media out and make it lighter and easier to handle .
EVAPORATIVE COOLING MAINTENANCE
IMPORTANT
Replacement media should be from the same
manufacturer and be the same size as the original
media provided with the unit .