How to install a heater core in a 2012 Volvo S60 You can also try flushing it. Mine was pretty clogged, even tried soaking it in lime away. Had to replace.
It only had heat for first couple of seconds, then it was cold, my heater core was pretty clogged up. I did try flushing it twice, the second time was with lime away, With this it only barely improved. Also if you try flushing it, and it is restricted, you know for sure it's blocked up. Good Luck.
