does mesh resolution affect heat conduction in solids? or just flow...

i have an electronic enclosure with a heat source, and a heat sink and fan. it seems like when i turn the mesh settings up, the heat cut plots show the same temperature, maybe a variance by 5°C. but the flow trajectories are a lot better, you can see their movement through the heat sink fins a lot better.

So I am wondering, if i just want to look at heat cut plots, will i gain any more accuracy using a higher mesh setting?