Danfoss VLT HVAC Design Guide

2.7.19 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 chiller's 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.
2.7.20 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.
VLT
®
HVAC Drive Design Guide 2 Introduction to VLT HVAC Drive
MG.11.B9.02 - VLT
®
is a registered Danfoss trademark 29
2

Danfoss VLT HVAC Specifications

General

Enclosure Rating	IP20, IP21, IP54, IP55, IP66
Storage Temperature Range	-25°C to +70°C
Output Voltage Range	0-100% of supply voltage
Communication Protocols	Modbus RTU, BACnet, Ethernet/IP, Profibus DP
Ambient Temperature Range	-10°C to +50°C (without derating)
Relative Humidity	5% to 95% non-condensing
Altitude	Up to 1000 m without derating
Cooling Method	Air cooled
Application	HVAC systems, Pumps, Fans, Compressors
Voltage Range	200-240 V, 380-500 V, 525-600 V
Frequency Range	0 Hz to 590 Hz