The goodness of a polynomial model for heat losses of a receiver tube from a parabolic through collector has been analyzed. This model was first proposed for receiver indoor tests by NREL. More than 50 commercial receiver tubes from the main international manufacturers were tested by CENER and Ciemat-PSA and the adjustment of the measured heat losses points to this model was checked. This study aims to validate the model proposed in the future international standard IEC 62862-3-2 and the Spanish standard UNE.