Danfoss VLT 6000 HVAC Series Design Manual page 21

Condenser pumps
Condenser Water pumps are primarily used to circulate water through the condenser section of water cooled
chillers and their associated cooling tower. The condenser water absorbs the heat from the chillers condenser
section and releases it into the atmosphere in the cooling tower. These systems are used to provide the most
efficient means of creating chilled water, they are as much as 20% more efficient than air cooled chillers.
The VLT solution
Frequency converters can be added to condenser water pumps instead of balancing the pumps with a throttling
valve or trimming the pump impeller.
Using a frequency converter instead of a throttling valve simply saves the energy that would have been absorbed
by the valve. This can amount to savings of 15-20% or more. Trimming the pump impeller is irreversible, thus if
the conditions change and higher flow is required the impeller must be replaced.
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MG.61.B5.02 - VLT is a registered Danfoss trademark
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VLT 6000 HVAC Series
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