I own a 2005 Volvo V70 2.4. This past winter I did not have hot air coming out of my vents, it was warm, but not warm enough on those below zero mornings. Thermostat was replaced at that time. Heat was warmer, but not what it should have been. This summer began with the A/C functioning normally with cold air. Shortly thereafter, I turned on the A/C and I no longer could control the blower motor speed. It would only come out at full blast, the little green LED lights never lit up (even after hours of driving and constant turning on/off of the ignition). Then one day, rather than frigid air, it turned into hot, stagnant air coming out of the vents at full blast. Talk about uncomfortable on those 80° days. Also the air that comes out when I turn on the defroster is hot and creates a thick film on the inside of the windshield that makes it impossible to see on a sunny day. What I want to know is if I am going to have to replace the whole climate system, or if I could have a leaky pipe or faulty wire somewhere within the whole system. I am seeing a Volvo mechanic next week, but I just wanted to know if anyone out there had experienced something similar in their Volvo.

 

The thick film sounds like you might have a leak in the heater core. But sounds like the climate system is on the fritz.