Influence of hot tool parameters on heat recovery in a space-heating and ventilation system

A study has been carried out on heat recovery from air that ventilates a hot tool in a tool shop. The recovered heat is used to preheat air for space heating of this tool shop. Software has been used to analyze the heat-recovery efficiency and thermal comfort (TC) when the size and temperature of the hot tool are varied. An increase in hot tool size of 10% yields an energy loss of up to 2% and temperatures of the tool-shop space that are 6% higher than the TC temperature. This energy loss can be avoided if we tune the heat-recovery system (HRS) to reach TC as before. A 10% decrease of hot tool size yields at most 5% in energy saving and a tool-shop-space temperature 6% lower than the TC temperature. Further HRS tuning to provide TC will reduce energy saving. Higher or lower tool temperatures do not appreciably change the energy expenditure.