User Manual

6
2 Basics
Air conditioning plants do not always enjoy the best of reputations. The reasons
mainly concern plant hygiene, partly incorrect plant design, often high energy
consumption as well, especially with older plants or certain designs. Nevertheless,
air conditioning plants perform important tasks and have an established place in
modern building control. A great deal of progress has been made in recent times,
especially with regard to plant hygiene, energy management, and plant equipment.
However, strategies for controlling air conditioning plants have hardly changed over
the past few years. For example, energy recovery is typically controlled according
to enthalpy, i.e. separate temperature and humidity control loops with their own
energy-neutral zones but without inter-harmonization. This method does not always
guarantee optimal behavior and generally is deficient with regard to dynamics.
This is where our Economizer tx2 comes in: Systematic exploitation of comfort
limits inter-harmonization of setpoints, process control, and energy recovery mode.
3 Economizer tx2
3.1 Overview
An air conditioning plant ready for operation with energy recovery serves as our
starting point. This air conditioning plant is tasked with providing adequate comfort
conditions (use-adjusted room conditions) at the lowest possible operating costs.
Minimizing operating costs, however, may not be at the expense of comfort.
The following aggregates can be used as air handling units:
– Hot water heating coil
– Chilled water cooling coil
– Steam humidifier, washer, spray humidifier
– Plate heat exchanger, rotating ERC, or mixed air dampers