Transiently accreting neutron stars in low mass X-ray binaries are generally believed to be heated up by nuclear reactions in accreted matter during hydrostatic compression .
Detailed modeling of these reactions is required for the correct interpretation of observations .
In this paper , we construct a simplified reaction network , which can be easily implemented and depends mainly on atomic mass tables as nuclear physics input .
We show that it reproduces results of the detailed network by Lau et al .
( 2018 ) very well , if one applies the same mass model .
However , the composition and the heating power are shown to be sensitive to the mass table used and treatment of mass tables boundary , if one applies several of them in one simulation .
In particular , the impurity parameter Q _ { \mathrm { imp } } at density \rho = 2 \times 10 ^ { 12 } g cm ^ { -3 } can differ for a factor of few , and even increase with density increase .
The profile of integrated heat realize shown to be well confined between results by Fantina et al .
( 2018 ) and Lau et al .
( 2018 ) .