Post on 09-Jan-2017
A publication of
Avoid icing on your counterflow cooling tower this winter. Follow these 12 rules for operating
your cooling tower in winter.
Rule #1
Complete a Fall Inspection
Rule #1
1. distribution headers
Inspect…
1. distribution headers 2. laterals
Inspect…
1. distribution headers 2. laterals 3. nozzles
**Ensure nozzles are clean and intact to provide even water distribution over tower fill. This will help to prevent icing.
Inspect…
Rule #2
Protect air-inlet opening
Rule #2
falls below 55 degrees, start implementing cold weather operations.
This begins with protecting the air inlet opening / louver area (if installed).
When water temperature…
falls below 55 degrees, start implementing cold weather operations.
This begins with protecting the air inlet opening / louver area (if installed).
When water temperature…
The most effective way to protect the air inlet opening, is to install tarpaulins on the windward side of the tower.
Rule #3
High heat load & water circulation rate
Rule #3
needs to be maintained at the highest possible level.
Once the air inlet opening is protected, all other components are protected if there is a substantial amount of plant heat load.
Plant heat load…
Circulating water flow should also be maintained at the highest possible rate by operating all usable pumps. This is to ensure a full warm water wash of the internal components.
Rule #4
What if there is no heat load?
Rule #4
the circulating water should be bypassed directly to the cold water basin.
If your tower is not equipped with a bypass capability, then shut down your tower completely.
If there is no heat load…
the circulating water should be bypassed directly to the cold water basin.
If your tower is not equipped with a bypass capability, then shut down your tower completely.
If there is no heat load…
See our Winter Shutdown Checklist procedure to ensure a proper shutdown during winter.
Rule #5
Complete visual inspections
Rule #5
under winter operations,
complete a visual
inspection of the tower
every 2 - 4 hours
depending on if the
ambient temperature is
within the rage of 20 -
40 degrees or below 20
degrees.
While running your tower…
While running your tower…
20 - 40
inspect every 4 hours
under winter operations,
complete a visual
inspection of the tower
every 2 - 4 hours
depending on if the
ambient temperature is
within the rage of 20 -
40 degrees or below 20
degrees.
While running your tower…
< 20inspect every
2 hours
under winter operations,
complete a visual
inspection of the tower
every 2 - 4 hours
depending on if the
ambient temperature is
within the rage of 20 -
40 degrees or below 20
degrees.
Rule #6
Maintain cold water temperature by regulating airflow
Rule #6
fans can be cycled from
full speed to half speed or
be completely turned off.
This is the most effective way to maintain cold water temperature and control ice formation.
To regulate airflow…
The cold return water should NOT
drop below 55 degrees
Fahrenheit.55fans can be cycled from
full speed to half speed or
be completely turned off.
This is the most effective way to maintain cold water temperature and control ice formation.
To regulate airflow…
Rule #7
When reverse fan operations are necessary
Rule #7
is still occurring, switch to
reverse fan operations.
Reverse mode should be
monitored continuously
and should only be used
for severe ice buildup
with systems that are
capable of this option.
If significant ice build up…
Rule #8
When shutting fans down
Rule #8
from rotating in the normal direction, allow at least 2 minutes before starting in reverse direction.
When fans are shut off…
{2 min.
Rule #9
Check the fan blades
Rule #9
for any ice buildup. If
your fan blades are free
from ice buildup, you
can now begin reverse
direction.
Check fan blades…
for any ice buildup. If
your fan blades are free
from ice buildup, you
can now begin reverse
direction.
Check fan blades…
**Even if the fans are still wind milling in the
forward direction, they can be reversed. Minimal
torque will be applied to the mechanical system.
Rule #10
Reverse operation timeline
Rule #10
ONLY for a maximum of
20 - 30 min.
Operate in reverse direction…
20 – 30 minutes{
Rule #11
Competing reverse fan operations
Rule #11
When reverse operation is complete… let the fan come to a complete stop before re-starting.
let the fan come to a complete stop before re-starting.
When reverse operation is complete…
Now with the fans shut off, flow water for 15 min to prevent ice
buildup in the plenum area. Again, visually check the fan
blades for ice buildup.
Rule #12
Never physically remove ice from structure!
Rule #12
Or try to physically strip the framework of the ice.
NEVER remove ice…
any ice buildup on the perimeter columns or the bottom of the fill.
**It is important to inspect this every 2-4 hours to prevent ice build up this heavy. (see photo to right)
Monitor frequently…
Remember:Melting will leave components in good condition where as physical removal of ice will generally cause
more damage.
Learn more about cooling tower winter operations: