A study of energy retrofit by combined heat pipe heat exchanger with cold condensate was carried out and results are presented in this paper. The parameters of study including inlet water temperature, water flow rate, primary air velocity, and exhaust air velocity on systems performance are experimentally investigated. Experiment results indicate that for a small condensate flow rate, both the latent heat of exhaust air and sensible heat of condensate can simultaneously be utilized for cooling and dehumidifying primary air, which is expected to be efficient for energy retrofit in central air conditioning systems.
Practical application: Cold condensate from Heating, Ventilating, and Air-Conditioning (HVAC) plants are usually discharged or drained off. Reuse of cold condensate not only reduces wastage of water, it also fully utilizes energy and improves overall efficiency of HVAC plants. The installation and capital cost for heat pipe heat exchanger are reasonable. The physical space required is also affordable. Its practical value is useful.
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