Models of heat production of broilers are used to design the thermal equipment to optimize climate control. The reference models are now around fifteen years old. Daily values of heat productions are deduced from the live weight of broilers and do not integrate the diversity of livestock systems and the genetic progress's evolution. Animal welfare and environmental issues now require simulations at an hourly time step or even shorter. Our objective is to propose an hourly model of heat, carbon dioxide and water vapor productions incorporating the zootechnical parameters specific of a commercial batch of broilers. To update the reference equations, we measured the heat fluxes of two lots of 4580 chickens, during 33 days, in conditions similar to commercial farming. Both breeding rooms were equipped with sensors for continuous recording of hygrometry, temperature, CO2 concentration, lighting duration, ventilation rate and heating. The usual zootechnical data enabled us to calculate the balance of water and carbon mass. We propose a new model design for heat production. The main parameters of the allometric relationship are calibrated with the nocturnal phases because of the observed stability of fluxes. Over the total duration of the batch, within a 24-hour cycle, heat outputs can vary between -1 W animal-1 and + 50 % of the night heat output. Since we cannot explain the kinetics during the daytime periods, we propose to border the total heat production. The value of energy conversion to CO2 has been updated to 0,197 L CO2 h-1 W-1. When indoor temperature remains near the temperature setpoint, diurnal evaporation increases when indoor hygrometry decreases.