It is common to see water cooled chilled water central plants provided with water side economizer. These economizer loops allows the cooling tower to become the primary source of cooling on low ambient outdoor conditions. The condenser water open loop and the chilled water closed loop are kept separate by a plate and frame heat exchanger (HX). In most cases the HX is connected in parallel with the chiller(s) on both sides, at the condenser loop (cold side) and at the chilled water loop (hot side). Depending on the building cooling load and outdoor wet bulb, the energy management system (EMS) automatically makes a change to enable the economizer or to use the chiller equipment. In order to differentiate these two modes of operation, during the process where the cooling tower is the primary source of cooling it is normally referred as “free cooling mode” otherwise it is referred to as “mechanical cooling mode”.

The Chil-Pak® Continuous Economizer Loop™ enables building owners to reduce their OPEX by taking maximum advantage of the outdoor wet-bulb temperatures. The strategic piping arrangement allows for an optimized combination of partial free cooling and complementary mechanical cooling. The Continuous Economizer Loop™ system is uniquely designed to improve energy efficiency by taking advantage of wet bulb temperatures as soon as they are low enough to make condenser water that is lower in temperature than the chilled water return. The Continuous Economizer Loop™ does not wait until the wet bulb is low enough to carry 100% of the load as is typically required on a traditional parallel system. The innovative design of The Continuous Economizer Loop™ system extends the number of hours of free cooling energy and it costs only a fraction more than a the parallel system.

Another advantage of The Continuous Economizer Loop™ is that it allows a smooth transition when the system cycles between full mechanical cooling, partial economizer mode, and total economizer mode.

The Chil-Pak® unit can also be equipped with a graphics interface device (GID) touch screen, which will display in real time, cooling load values in tons performed by the chiller equipment and tons performed by the economizer. The graphic interface device also records and displays the ton-hours of free-cooling and ton-hours of total mechanical cooling.

If equipped with the optional electrical energy meter, the GID will also display real time total KW/Ton and will record the KW/Ton in parallel with the economizer system metering.

The system can be furnished with a Web based remote monitoring system or with a telephone modem so that the Chil-Pak® team can monitor The Continuous Economizer Loop™ performance and energy savings from anywhere in the world.

As energy optimization strategies are considered it is important to note that The Continuous Economizer Loop™ automatically implements The Low Load Controller™ at no additional cost.