Using Interval Timers to Control Evaporative Cooling Pads

This helps me understand better in getting best result in tunnel ventilation.

Better understanding of ventilation management for a poultry house under high temperature & high external humidity conditions with energy (electricity) input conservation.

When you install / use a regular House Climate controller an interval timer is included and automatically decide the length from the ON and OFF time from the waterpumps. For example when you program a total cycle of 5 minutes the Controller will “”calculate” the ON and OFF time being depending on the difference between the Temperature setpoint and the actual in-house temperature. For example: when the temperature inside gets 2 degrees higher as the setpoint than the waterpump will be ON 1 minute and 4 minutes OFF. When inside 2,5 degrees higher as setpoint ( because outside temperature gets higher) after the completion from the 5 minutes*) cycle the waterpump will be ON for 2 minutes etc. etc.. This will continue until the in-house temperature is close to the Setpoint. The PAD-cooling waterpump should never operate continuous adding to much water to the PAD,s increasing the Humidity too fast-too high. At a (too) high humidity inside the house, starting around 70 to 75% the PAD-cooling is loosing his effect and more ventilation ( air velocity) will be needed to cool the BIrds through the “Wind-chill effect”. *) The length of the mentioned cycle from 5 minutes can be adjusted which depends on the house dimensions, PAD-cooling surface , the total Fan capacity and the specification of PAD-cooling system.

My experience has shown that intermittent pump shutdown has two downside effects. If the pads are not clean you may not be getting the water saturation needed and depending on the water supply you may get excessive calcium or scale build up on the pads reducing efficiency.