BAC Trillium Series Operating And Maintenance Instructions

ADIABATIC PRE-COOLING MEDIA
About Adiabatic Pre-Cooling
Airborne debris is caught in the adiabatic pre-cooling media. They act as an air filter and as such protect the heat
exchanger coil from rapid and excessive fouling. During adiabatic operation the media is 'rinsed' by water
overfeed. The debris, that is rinsed from the media, will drain together with the excess water.
The pre-cooling media can be removed during cold seasons, as soon as it is guaranteed that the ambient
temperature will no longer exceed the dry-to-adiabatic switch point. This will extend the service lifetime of the
media. It will however increase the speed of fouling of the dry heat exchanger coil.
At least every quarter an inspection of the adiabatic pre-cooler media is recommended, also during mid-season and
winter season when usually no adiabatic cycles would be needed.
The inspection should focus on:
• Signs of excessive fouling and scaling of the media
• Full and even wetting of the face area
Float switches
• Check that the float switches can move freely
Fouling
If excessive dirt and debris has accumulated on the pre-cooling media, it is recommended to rinse the media.
Refer to "Adiabatic pre-cooling media" on page24 for the recommended procedure for cleaning and rinsing of the
media.
Scaling
Scaling will deposit on the pre-cooling media, every time that the pre-cooling media dries at the end of each
adiabatic cycle. The rate of scaling will depend upon:
• The number of adiabatic starts and stops per day
• The water quality
• The water flow over the adiabatic pre-cooler
The expected service lifetime of the pre-cooling media is 5 to 7 years if basic housekeeping practices and these
operating and maintenance guidelines are followed.
If excessive scaling is accumulating too fast on the pre-cooling media, the following checks and adjustments need
to be made:
• Check and adjust number of adiabatic starts and stops:
refer to "Checks and adjustments" on page15, section "Adiabatic Controller Set-Point".
• Check and adjust water quality:
refer to section "About water care" on page8
• Check and adjust water flow distributed over Adiabatic Pre-Cooler:
refer to section "About water care" on page8.
HEAT EXCHANGER COIL
The finned heat exchanger coil is susceptible to corrosion and entrapment of airborne particulates (coil fouling).
The speed of coil fouling can be reduced, and the service lifetime of the finned coil can be extended, if the pre-
cooling media is kept in place also during cold seasons, to act as air filter.
The heat exchanger coil requires periodic cleaning to maintain the highest operating efficiency possible under the
environmental conditions in which the dry unit operates. Regularly scheduled coil cleaning makes a significant
contribution to extending equipment lifetime and is an excellent source of energy conservation.
W W W . B A L T I M O R E A I R C O I L . E U
18

BAC Trillium Series Specifications

General

Brand	BAC
Model	Trillium Series
Category	Air Conditioner
Language	English