OK, OK, so I don't own my Blazer anymore, but I trust the opinions of my guys in here still, so that's why I am asking this here.

So as many of you know, I have a 1997 Dodge Grand Caravan now. I have an issue that is puzzling me that hopefully you guys can help me out on.

When I turn the defrost on, a very strange smell occurs. I would describe it as, not a burning smell, but also, not a wet smell. It sort of smells like something was wet, but at the same time, it smells like something burning. I know, it's an odd smell to describe so that's the best I can do on a description. This only occurs when the defrost is on, and NEVER when the regular heat is turned on. If I turn it to combo the defrost and heat on the floor, the smell occurs, and when it is defrost on it's own.

Any ideas? I'm stumped.

 

Needs new A/C Filter Drier/Accumulator. Whatever they're called nowdays. The defroster setting uses the AC system to dry the air. Sounds Moldy.

 

It does sound like it's in the evaporator core area, because it's recycled air in defrost mode. You'll probably smell it if you use the A/C as well. (Although I'm sure that you won't need the A/C for a few months yet)
There are some products that you can buy that you spray into the intake duct (near the right side of the firewall), while the heater fan is running. There are deodorizers and products to kill the mould also.
I haven't used them for years, you could check with your local parts store or and auto A/C shop.
That might work. If it doesn't, then you'll have to access and possibly have to remove the evaporator core to clean or replace it.

The accumulator is a closed system that contains refrigerant, refrigerant oil and a dessicant (to remove internal moisture),and will not cause any smell in the vehicle.

 

Thanks guys!