2007 S80 heater not working

[Wetlander]

Greetings - after the diagnosis mentioned in my Dec 17, 2019 post, I went ahead and swapped out the heater core in the S80 and voila - I now have heat. After unhooking the old core, I turned it over to drain it and a bunch of sediment came out with the coolant, thus confirming there was a blockage in the core. Once I find the time, I hope to post a description of the process I followed for replacing the heater core. It's not a job for the fainthearted, but it saved me a lot of money. Anyway, I don't have any advice for you thelwthelw, but I wish you luck in fixing your problem.