Control system for animal house ventilation - has programmer with five minute cycle and high and low limit thermostats giving alternative control sequences

摘要

The system has a programmer with a maximum cycle time of five minutes with a choice of two different sequences. A high limit thermostat completes the ventilation cycle automatically if necessary and a low limit thermostat stops it. A thermostat with two or more detectors initiates the reversal of the direction of ventilation to accelerate the start of reverse flow if the temperature within the house continues to rise. The control is supplied through a multi tap transformer. The ventilation fans are reversible and have electrically operated inlet and discharge shutters. There is also a hygrostatically controlled humidifier. The system gives accurate control of the rate of air change whilst maintaing an even temperature and prevents overheating in summer.