Pupils using the Orchard Centre complained it was too warm. Investigation found boiler running and radiators on, but windows open. Boiler is a simple Baxi controlled by a portable thermostat. Found thermostat date and time wrong - corrected. Found time programmes wrong - corrected to match desired occupancy. Found heating set point set way too high - reduced to 18C. Found heating in manual ON mode - reset to Auto mode. Turned heating OFF for summer run heating not needed. Locked thermostat controls to reduce possibility of pupil tampering. Ordered tamperproof locking cover for thermostat to further reduce risk of tampering.