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Old 03-25-2008, 01:56 PM   #1
jamon8
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heat blowing cold

boy am I glad the temps are up here in S IL

all of a sudden my heat is blowing cold

any ideas
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Old 03-25-2008, 02:37 PM   #2
69rut
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Re: heat blowing cold

Here are some ideas:
Heater core blocked, this could be internal or external

Fan motor not working, fan broken

Thermostat stuck open

Heater control valve closed

Cab duct work not in proper position
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Old 03-25-2008, 02:39 PM   #3
special-K
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Re: heat blowing cold

Low on coolant?
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Old 03-25-2008, 03:50 PM   #4
lks dcvn
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Re: heat blowing cold

Just a guess, but there could be leaves, pine needles, rodents, etc. living in your heater box...

Mine works well enough in my beater, but I will be taking the cowl off - cleaning that stuff out (putting a fiberglass screen under the cowl opening) and putting it back on...

Then I will be removing the box under the hood and making sure that everything is clear (no junk in there) and then giving it another run...

I have been told that the heaters in these trucks sometimes work too well...

When I turn on my blower in the cab - I get an assortment of leaves, etc. that comes out of the ductwork (top of the dash and below) so I know that there is stuff in there...just hasn't been warm (and dry enough) to do it yet.

The other options are also valid.

Good luck.
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Old 03-26-2008, 03:10 PM   #5
jamon8
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Re: heat blowing cold

thanks guys for the quick replies

all of a sudden the heat started to work yesterday

I am going to check the coolant level today and the cowl
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