Checking/cleaning air intake for A/C and heat?

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SubDominant

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I have been on a search and destroy mission in my Burb. Destroy all mouse nests!! Remove all mouse turds!!

I have disassembled the ducting and heater box from inside under the dash (including defrost ducting). I am going to do a deep clean on all parts and replace the core. Good thing so far is no nests or turds inside any of the ducting or heater core. But I am wondering about the fesh air intake for the blower. Is there a way to check/inspect the inlet? I am not sure where it is so I am asking the forum for help. I would hate to get this back together and then just blow a bunch of crud into my newly cleaned duct work - and especially into the lungs of my passengers (read wife).

Thanks for all of your help!
 

Craig 85

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Here's a picture of the cab. Air enters at the yellow arrow and flows down the inner firewall to the round circle where the blower motor/squirrel cage is. On an A/C truck in Max mode, it will pull air from the passenger kit panel.

Air flow then follows the red arrow into the engine compartment and through the heater box or heater A/C combo. From there it enters the inside of the cab and goes into the yellow box in photo #2.

FYI, the pictures are for an A/C cab and in photo #2 the part of the heater box in the background, should lay on top of the piece in the foreground.

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SubDominant

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Here's a picture of the cab. Air enters at the yellow arrow and flows down the inner firewall to the round circle where the blower motor/squirrel cage is. On an A/C truck in Max mode, it will pull air from the passenger kit panel.

Air flow then follows the red arrow into the engine compartment and through the heater box or heater A/C combo. From there it enters the inside of the cab and goes into the yellow box in photo #2.

FYI, the pictures are for an A/C cab and in photo #2 the part of the heater box in the background, should lay on top of the piece in the foreground.

Thanks for this! :happy107: So what I am gathering is that I should remove the blower motor to see if any nesting material is gathered at the inlet? I am hoping I do not have to remove the passenger fender.

And if anyone is wondering why I want to clean the ducting take a look at this thread:
https://www.gmsquarebody.com/threads/need-help-on-cleaning-cowl.30077/#post-588219
 
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Craig 85

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You can remove the kick panel on the passenger side and access most of that area. The vent door is attached to the kick panel.

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Scott91370

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In the first picture you can pull the blower motor which is in the round hole at the back side of the arrow. This will allow you to reach inside the box as well.
 

SubDominant

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You can remove the kick panel on the passenger side and access most of that area. The vent door is attached to the kick panel.

Kick panel removed and inspected. Looks real clean surprisingly. Pics to come later. Thanks!
 

SubDominant

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In the first picture you can pull the blower motor which is in the round hole at the back side of the arrow. This will allow you to reach inside the box as well.

Yup. This is next on my list.
 

austinado16

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Excellent explanation and photos! A few weeks ago, I discovered my vacuum hose to the fresh air flap inside that hollow firewall area, had broken, pulled out of the firewall, and was laying in around the wiring that goes to he glove box light. No idea how it got broken, how long ago it happened, or how it got pulled out of the firewall, but it was info like what's posted above, that helped me to fix it.
 

SubDominant

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Pics of inside the kick panel
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SubDominant

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Moved on to the blower:
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A look inside the air box and not too bad. Don't think that's mouse turds in there. No nesting material at all. Just some debris. And look, the nut for my blower cage!
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Vacuumed what I could, hosed off the blower cage and put it back together.
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Bower works. Next is figuring out if my AC actually works, cleaning the ducting and putting it all back together.
 

tomtom1954

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If your truck sits alot or is stored, put some cheap dryer sheets from a dollar store around your truck. Mice hate them. I even have them folded and stuffed in the vents. i left some sticking out so I can pull them out.
 

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