\documentclass[border=3mm]{standalone} \usepackage{luacoolprop} \pgfplotsset{compat=1.18} \begin{document} \begin{tikzpicture} \begin{axis}[lcp fluid=R134a,width=13cm,height=8cm,xlabel={$h/\mathrm{kJ\,kg^{-1}}$},ylabel={$p/\mathrm{bar}$},ymode=log,grid=both,auto node placement] \LCPAddPHIsotherms[ temperature values={-30,0,30,60,90,120}, labels=true, isotherm label sloped=true, isotherm label every=1, isotherm color=orange!80!black] \LCPAddPHQuality[ quality values={0,0.1,0.3,0.5,0.7,0.9,1}, labels=true, quality label sloped=true, quality label every=1, quality color=teal!65!black, quality boundary color=teal!90!black] \end{axis} \end{tikzpicture} \end{document} .