Central heating fuel economy system - has heat-up time circulated from difference between internal and ambient temperatures

摘要

The system economises fuel in a building central-heating system by cutting out heat-generation during slack periods and cutting it in again in sufficient time before demand resumes. Ambient temperature and also mean internal temperature are taken into account in determining the appropriate moment. The heat-up time is a function of the colling-down time elapsing after cut-out and also of the difference between internal and external temperatures, and of a constant. The latter is arrived at from a base value by measuring the actual time for heating-up and comparing it with the calculated value.