Most buildings have internal heat gains and losses due to people, passive solar heating, or opening of doors. If only the outdoor temperature is measured, the control cannot compensate for these heat gains/losses and overheating or underheating may occur. Indoor temperature feedback prevents this by shifting the heating curve up or down,
in order to fine adjust the supply water temperature to the heating terminals. Single or multiple tekmar Indoor Sensors or Room Temperature Units (RTU) are required to provide the feedback to the Reset Controls. This function provides more comfort by preventing overheating or underheating.