$$COP = a_0 + a_1 (\overline{T}_w - \overline{T_a}) + a_2 (\overline{T}_w - \overline{T}_a)^2 + a_3 (\overline{T}_{wet} - \overline{T}_{dp})$$

$$Power = p_0 + p_1 \overline{T}_w + p_2 \overline{T}_w^2 + p_3 \overline{T}_a$$