Cold Weather Operations; About Cold Weather Operation; Protection Against Coil Freezing - Baltimore Aircoil Company Trillium Series Operating And Maintenance Instructions Manual

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COLD WEATHER OPERATIONS

About cold weather operation

BAC cooling equipment can be operated in sub freezing ambient conditions provided the proper measures are
taken. Listed below are general guidelines which should be followed to minimize the possibility of coil freeze-up.
As these guidelines may not include all aspects of the anticipated operation scheme, system designer and
operator must thoroughly review the system, location of the equipment, controls and accessories to ensure reliable
operation at all times.

Protection against coil freezing

The best protection is the use of glycol or other anti freeze solutions in appropriate concentrations. The use of such
solutions influences the thermal performance of the cooler and this should be taken into account, when selecting
the model(s). The table below indicates the freeze protection range for various ethylene glycol concentrations (%
by volume).
Glycol systems require specific inhibitors compatible with the materials of construction they come into
contact with. These inhibitors generally come pre-mixed with the glycol additive for the cooling circuit.
If the process load is extremely light or shut off, it may be necessary to apply an auxiliary heat load during freezing
conditions. Consult your local BAC Balticare representative for advice.
A full coil drain of the heat exchangers is not possible and as such, this method cannot be relied upon to
protect fluid coolers operating under ambient temperatures that could drop below freezing point, from
damage to the coil.
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W W W . B A L T I M O R E A I R C O I L . E U
% Ethylene
20%
30%
40%
50%
Freeze protection of ethylene glycol solutions
Freeze protection
-10°C
-16°C
-25°C
-39°C
4 Cold weather operations
4 Cold weather operations