2nd Gen Non-Engine/Transmission Air flow

[RClark]

It seems the airflow out of the heater/AC has diminished after 12 yrs.

What usually causes this and how can it be improved without a complete disassembly of the system?

 

[Bob4x4]

Dirt coating the evap and heater core is fairly common

 

[RClark]

Is there a easy way to remove this?

 

[Bob4x4]

Drop the blowers motor out and reach in if you can flex enough to get the big stuff out then blow out the best possible with compressed air

 

[GAmes]

After vacuuming the plenum as best you can you can also spray some non-corrosive cleaner into the heater fins then use low pressure water to rinse it out. If you don't introduce too much water it will drain from the A/C drain.

 

[HHhuntitall]

... . if the drain isn't stopped up from dirt. I usually find excessive pet hair and tree leaves in them when I remove them. The best way to completely unstop it is to remove it..... but that's not an easy chore, in any way, let alone recovering the Freon in the system before disconnecting it, so I'll presume you'll want to do it the way above.

I usually reach up through the fan motor hole, using a shop vac with some stiff plastic bristles. It works ok, then a siphon gun with some clean water to blow the rest out and down to where it will drain..... A plastic zip tire works to unstop the drain repeatedly if it has a lot of dirt in it... ...

Ironically, I just did this to a Peterbilt yesterday morning..... It looked like a small animal had gotten caught up in it..... But on those, the heater core comes out pretty easy, giving you access to the evaporator.....