Volvo Repair: Is it the battery?, many different things, car place

Question
Thank you so much for getting back to me. I ended up jumping the car and then taking it to a car place (not the dealership!). They put a new battery in it and then put a pound of freon and ran dye through the system to check on the air conditioner. On the way home, my air conditioner started great and then petered out. I hear a hose sound blowing when I first start the car sometimes. After the air stops and I start the car, it will sometimes start again and be nice and cold. It is a 1999 V70 so I am baffled about the air. I am going to run it up to them Friday so they can see if the dye showed a leak. What do you think?
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Followup To

Question -
I left my keys in the ignition overnight but did not think anything was turned on. I tried to start my V70 this AM and heard a click and then nothing. My headlights and dashboard indicators all work. Can this still be my battery if my lights and dashboard work?

One other question (sorry). My air conditioning will go off intermittingly. I hear a blowing sound and then it stops sometimes. Because my air conditioning works great sometimes, can this still be a hose or does it sound electrical?Thanks.

Answer -
The lights could be on and the battery can be dead.  They require very little power to operate but the starter requires all the juice the battery can muster.  There are many different things that could be wrong with the other items, I need to know exactly what year the vehicle is though because alot has changed from 1998-2007 in the V70 line.

James

Answer
Well most likely your problem is the evaporator i'm sorry to say.  That is the most expensive, hard to replace item in the air conditioning system.  It is the only thing that really ever goes bad on that car however.  2001 and up its almost always the compressor, 1998-2000 its always evaporators.  The kit is 400-500 dollars and 10 hours of labor to remove the dashboard, climate unit and replace the evaporator.  The hissing blowing sound from the A/C is mostlikely the orifice tube.  It reuglators the high to low pressure in the system.  It has a little filter screen on it that if it tears will make hissing sounds when the system is still pressurizing or right after the car is turned off.  They can replace it very easily when the A/C system is evacuated and it is only a couple dollars for that item.

James