EVALUATING RADIANT HEATER PERFORMANCE USING CHICK THERMAL PREFERENCE AND SPATIAL ANALYSIS

Radiant heaters are the most common method of providing supplemental heat in broiler houses, but little is known about how efficiently they create a suitable thermal environment for brooding chicks. This study investigates the net usable area (NUA), or the total floor area within the range of radiant flux preferred by chicks, for six round radiant heaters with a nominally rated power output of 11.72 kW. NUA was calculated for all heaters at three manufacturer specified heights 1.52, 1.83, and 1.98 m and at a distance 0.3 m below manufacturer specified height (1.22 m). NUA ranged from 11.6 +/- 0.7 m(2) to 59.4 +/- 19.7 m(2) and increased with heater mounting elevation. Results indicate that radiant heaters from different manufacturers with the same power output do not produce the same NUA. NUA was also shown to be higher at 8 d than 1 d for all heaters and was attributed to the decrease in chick preference for level of radiant flux during the first week of brooding. NUA gross radiant coefficient (GRC), or the proportion of the heat energy in the fuel that reached the floor and was within the thermal comfort range of the chicks, did not exceed 0.37 for any heater and decreased with heater elevation. Operating a heater below the manufacturer specified mounting elevations led to reduced NUA and an overall less efficient use of fuel.

Automated summary

This study investigated the efficiency of radiant heaters from different manufacturers in providing a suitable warm environment for brooding chicks, finding that heaters with the same power output do not necessarily produce the same net usable area (NUA). Additionally, chicks were shown to decrease their preference for radiant flux levels during the first week of brooding, resulting in higher NUA at 8 days compared to 1 day.