This research was conducted in a poultry farm within the poultry fattening project in Sohag Governorate, Egypt. Latitude 26.556 and longitude 31.655, village of Al-Ahawi. This research aims to maximize the utilization of the current cooling system for the broiler poultry houses. The experiment was conducted in station No. 2 using 6 houses at a poultry age 35 days on 3 July 2018 where the mean ambient temperature was 30.5 ^oC and the mean relative humidity was 47.4 %. The operating time of the cooling units under test was 8 hours, from 9:00 am to 5:00 pm. It should be noted that before 9:00 am all the houses were cool under the operating conditions of house4. The data showed that highest temperature increase was achieved at operating house 3 conditions (The cooling units are operated with nozzles arrangement (3) and air speed 2.5 m/s) with a value range of 19.3 : 26.3 ^oC (Avg. = 24.7 ^oC) while the relative humidity ranged from 64.1 to 69.3 % (Avg. = 65.7 %). It is not recommended that the fans run at operating points 3 (Air speed 2.5 m/s) under the same experimental conditions. It is recommended that reduce the number of nozzles inside cooling units from 12 to 8 or 10 nozzles leading to decrease relative humidity under the same experimental conditions. To reduce evaporation rate and rationalization of water consumption by 22 l/hr, cooling units are used under operating conditions of houses 5 or 6 compared to house 4. Operating conditions for houses number 5 and 6 give total energy and cooling efficiency near normal operating conditions (house 4). But rationalization of water is a major reason to urge on change normal operating of the traditional cooling system and move forward to replace those traditional systems with the latest systems.