iWorx® MPU2
505-009, Effective: April 28, 2014
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© 2014 Taco Electronic Solutions, Inc.
Figure 13: Modulated Staging with 2 Stages; 1st Stage Modulating
Economizer Operation
The MPU2 provides support for either two-position or modulated economizer types. You can specify which type of
economizer you are using through a configuration parameter. Both economizer types are enabled based on the avail-
ability of “free cooling” from the outside air. Free cooling can be determined by enthalpy comparisons or dry bulb com-
parison. In order to provide maximum energy savings, the cooling stages are interlocked with the economizer.
Figure 14: Economizer Control