Heatwaves in Ireland (a.k.a. nice warm weather for once) are mostly welcome. I would have thought that in Germany the word 'heatwave" - the title of this work - has a more negative connotation, but someone in Dortmund just bought a large print of this work. 
https://www.artheroes.com/en/shopartwork/Heatwave-I/1245894/132
@WesternExposure Maybe they live in a cold corner of Dortmund? 
It could also show an insight into a blast furnace in the Ruhr area.
I think the painting has a wonderful intensity and composition - and I would look at it independently of the title.
@NatureMC Good point. Maybe a retired steel worker.