Author Topic: Interior gets super hot even with the heat/blower off  (Read 426 times)

79transmass

  • Active Forum Member
  • *
  • Posts: 39
Interior gets super hot even with the heat/blower off
« on: May 13, 2018, 04:50:46 PM »
79 trans am, olds 403, stock. When driving on a decent day/night say 60 degrees or so out you can still feel a very noticeable amount of heat around your legs in the interior. The blower doesnt work currently so its not blowing heat but idk whats allowing all this heat in. Is it just the design of these cars? Do they just have poor insulation in the floors/firewalls? Any ideas or does anyone have any similar issues? In the summer its insanely hot to be in the car even with windows down

Jack

  • Oracle Forum Member
  • *
  • Posts: 9697
  • 1971 Esprit TA Clone W72 1972 Formula 68 350 HO
Re: Interior gets super hot even with the heat/blower off
« Reply #1 on: May 13, 2018, 05:35:28 PM »
The heater core is inside the car and hot coolant is passing through the cabin. Mine is bypassed.




Regards, Jack

Box

  • Oracle Forum Member
  • *
  • Posts: 5878
  • (>*.*)>#<(*.*<)
Re: Interior gets super hot even with the heat/blower off
« Reply #2 on: May 13, 2018, 07:48:29 PM »
Yup, coolant is always going through the core.  If you live where you use the car year round and you still use the heat you can put a valve in the route to the heater core, so then you can kill flow during the summer and then restore flow during the winter.  If it's only used when it's hot outside then just bypass it completely if you want.

1996 Pontiac Firebird Formula hardtop 6-speed

79transmass

  • Active Forum Member
  • *
  • Posts: 39
Re: Interior gets super hot even with the heat/blower off
« Reply #3 on: May 14, 2018, 12:45:33 PM »
Ahhh yes that makes sense. If I wanna bypass it where is a good place to put a valve? Also, any input on what valve specifically?

Box

  • Oracle Forum Member
  • *
  • Posts: 5878
  • (>*.*)>#<(*.*<)
Re: Interior gets super hot even with the heat/blower off
« Reply #4 on: May 14, 2018, 10:15:56 PM »
I just saw where you said the blower isn't working, so can just loop the out into the in versus having it go into the heater core for now.  If you want to do a valve on the out to the heater core, they're called shut off valves or heater core shut off valves to find automotive specific ones.

1996 Pontiac Firebird Formula hardtop 6-speed

Re: Interior gets super hot even with the heat/blower off
« Reply #4 on: May 14, 2018, 10:15:56 PM »

Dandy77

  • Active Forum Member
  • *
  • Posts: 442
Re: Interior gets super hot even with the heat/blower off
« Reply #5 on: May 16, 2018, 09:47:19 PM »
Jack what did you use to by pass? I am looking for a set up so I can by pass in the summer but not in the winter. Preferably electric set up.

Aus78Formula

  • Oracle Forum Member
  • *
  • Posts: 8392
Re: Interior gets super hot even with the heat/blower off
« Reply #6 on: May 16, 2018, 10:26:18 PM »
Aa per other link, use a vacuum valve and run it into one of the heater controls as also vacuum controlled. That way you can simply forget it.

Dandy77

  • Active Forum Member
  • *
  • Posts: 442
Re: Interior gets super hot even with the heat/blower off
« Reply #7 on: May 17, 2018, 07:03:40 AM »
Forgot to mention, non AC car.

Aus78Formula

  • Oracle Forum Member
  • *
  • Posts: 8392
Re: Interior gets super hot even with the heat/blower off
« Reply #8 on: May 17, 2018, 07:49:44 AM »
Aah ignore that then, one major issue is lack of working fan for air flow. That is designed to be constant and recognised as a requirement from new.

Re: Interior gets super hot even with the heat/blower off
« Reply #8 on: May 17, 2018, 07:49:44 AM »
You can help support TAC!