No heat in sleeper

That's why I placed webasto in my sleeper. Have it on when warm up the truck, when during sleeping hours.

 

I have volvo 2008 and it's not blowing heat at idle but heat when rolling. Please I need help. Am owner op

 

Found the issue it was the cabin air filter dirty as #### when I pulled it out and tried it it was blowing cold as new

 

Can you show a picture where this is and how to do that? Thanks.

 

That post was from 2013. That individual hasn’t been here since 2015.

 

Can anyone help with that issue? I have no heat in my bunk for my 2011 peterbilt 386. The coolant lines underneath are hot. I first lost the ac then now the heat stopped. The fan does work.