Commercial Energy Systems

Two Pipe Systems


Two pipe systems consist of a network of insulated pipes; one pipe supplies water chilled by a central chiller and the second pipe returns it to the chiller. With water-changeover, chilled water is circulated during the cooling season and hot water during the heating season. The problems occur during the mid-seasons where cooling can be required part of the time and heating part of the time and no heating or cooling the rest of the time. Due to the operating difficulties of changeover there will be times where tenants cannot get heating and cooling when they want it.

two pipe system

Two pipe systems without water-changeover circulate chilled water only and provide heat where it is needed by electric strip heat at the terminal units. In some cases, hot water is circulated during the coldest part of the heating season to reduce operating cost.

Links to Related Topics

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Central Plant System
Central (or Built-Up) System
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All-Air Rooftop
Air-Water Central Systems
All Water Central Systems
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