Experimental investigation of a high efficiency electric heater and dehumidifier prototype unit

Abstract

In this paper the principle of operation and preliminary laboratory measurements of a prototype of a high-efficiency electrical air heater unit is presented. Unlike conventional heaters, which apply Joule-heat formed by electrical resistance, the developed device uses thermoelectric modules for heating ambient air. Just like in case of resistance heaters, most of the heat is produced as a result of the internal ohmic resistance of the thermoelectric module (resistance heating), however, in case of appropriate air conditions our device is capable of transforming the latent heat of the air moisture into heat energy. In case of condensation mode, some of the moisture condensates on the cold side of the module while its latent heat is transferred to the hot side of the module where it heats the dried air. In this mode, the heating efficiency of the device (e.g., the ratio of the heat added to air and the consumed electricity) is over unity. Following the idea and basic equations of the operation of this device, the results of the laboratory measurements in a climate test chamber is presented.