Tech / General Engine Is your car making a strange sound or won't start? Thinking of adding power with a new combination? Need other technical information or engine specific advice? Don't see another board for your problem? Post it here!

Why does coolant run through the HVAC?

Thread Tools
 
Search this Thread
 
Old 07-13-2014, 07:15 PM
  #1  
Member
Thread Starter
 
Renier's Avatar
 
Join Date: Sep 2013
Location: The Netherlands
Posts: 184
Likes: 0
Received 0 Likes on 0 Posts
Car: '89 Camaro RS
Why does coolant run through the HVAC?

Well, I was wondering why coolant runs through the HVAC? I just managed to get my HVAC operational again by replacing the fuse, but my coolant supply from the engine to the HVAC is blocked off, the coolant is directly reintroduced into the engine instead with a single hose running to and from the engine instead of through the HVAC. Am I at risk of breaking something in the HVAC or will my HVAC work less properly due to this?

Thanks in advance, guys!
Old 07-13-2014, 07:24 PM
  #2  
Supreme Member

iTrader: (20)
 
Orr89RocZ's Avatar
 
Join Date: Sep 2003
Location: Pittsburgh PA
Posts: 25,749
Received 369 Likes on 298 Posts
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: Strange 12 bolt 3.42
Re: Why does coolant run through the HVAC?

Lol the hot coolant is how the hvac generates heat for the fan to blow. Thats why in the winter, you have to wait til car heats up before hot air is blown
Old 07-13-2014, 07:54 PM
  #3  
Junior Member
iTrader: (3)
 
KILLemALL's Avatar
 
Join Date: Oct 2012
Posts: 37
Likes: 0
Received 0 Likes on 0 Posts
Car: 77 Y82
Engine: W72
Transmission: Super T-10
Axle/Gears: 3.23
Re: Why does coolant run through the HVAC?

You won't hurt anything if your heater core is bypassed,you just won't have heat to the cockpit

Last edited by KILLemALL; 07-13-2014 at 07:57 PM.
Old 07-13-2014, 07:55 PM
  #4  
Senior Member

iTrader: (3)
 
Lurbie's Avatar
 
Join Date: Jul 2011
Location: Davison, MI
Posts: 744
Received 5 Likes on 5 Posts
Car: 89 Camaro
Engine: 383-Holley Terminator EFI
Transmission: 700R4 Pro-Built Street/Strip kit
Axle/Gears: Strange S60 3.55:1
Re: Why does coolant run through the HVAC?

What Orr said is correct. This is how the heater works. It is likely that someone bypassed the heater core because it was leaking and they didn't want to replace it. If you decide you want or need heat in your vehicle, be ready to check for leaks as soon as you hook the hoses up to the heater core. It is always a possibility that the PO (previous owner) disconnected the heater core for some other reason, but on a street car I can't think of a good reason to do so.
Old 07-14-2014, 03:28 AM
  #5  
Member
Thread Starter
 
Renier's Avatar
 
Join Date: Sep 2013
Location: The Netherlands
Posts: 184
Likes: 0
Received 0 Likes on 0 Posts
Car: '89 Camaro RS
Re: Why does coolant run through the HVAC?

Alright, makes sense. Thanks a bunch, guys!
Old 07-14-2014, 12:20 PM
  #6  
Supreme Member
 
rusty vango's Avatar
 
Join Date: Jun 2011
Location: knoxville tn
Posts: 2,036
Likes: 0
Received 5 Likes on 5 Posts
Car: 86 IROC
Engine: 5.0 TPI
Transmission: 700-R-4
Axle/Gears: 2.73 open
Re: Why does coolant run through the HVAC?

be advised, that if your heater core IS leaking. you cant buy a real deal core anymore. all the parts houses only sell aluminum or worse PLASTIC!! you can remove your original one and have it repaired at your local radiator shop.
Old 07-16-2014, 05:54 PM
  #7  
Member

 
draco's Avatar
 
Join Date: May 2006
Location: Parkersburg WV
Posts: 418
Received 1 Like on 1 Post
Car: 1992 Camaro RS 25th Anni.
Engine: 5.0l TBI
Transmission: 700R4 Automatic
Axle/Gears: 3.73 Gov lock
Re: Why does coolant run through the HVAC?

also be advised that a leaking core may allow coolant onto//into your pcm
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
1992 Trans Am
History / Originality
27
05-10-2023 07:19 PM
Casey Meyers
Interior Parts for Sale
8
03-02-2016 10:46 AM
TheExaminer
Cooling
26
08-26-2015 04:59 PM
eightsixseven
Tech / General Engine
1
08-14-2015 03:09 PM



Quick Reply: Why does coolant run through the HVAC?



All times are GMT -5. The time now is 11:00 PM.