Author Topic: Switching from an A/C HVAC control unit to a non-A/C HVAC inut.  (Read 1790 times)

Offline cosmic_3000

  • New Users
  • Posts: 2
  • Newbie
Hello All,

I've got a 78 K10 that originally came with A/C equipped. Since then the A/C components in the engine compartment have been removed (except the evaporator). Which means I have a control unit in the dash does has all the settings for A/C, but they don't do anything.

My question is, can I install a non-A/C control unit and work just fine? One that has the simple heater/defrost settings? Will it plug and play?

Thank You

Offline zieg85

  • Global Moderator
  • Senior Member
  • ****
  • Posts: 7543
    • 73-87 GM squarebody extended cab and conversions up to 91 R/V series
Re: Switching from an A/C HVAC control unit to a non-A/C HVAC inut.
« Reply #1 on: March 10, 2020, 08:22:06 PM »
The AC controls vacuum motors vent, floor, dash while the non-AC is all cable.  May be possible to convert but I am not sure how you would go about that.
 
Carl 
1985 C20 Scottsdale 7.4L 4 speed 3.21
1986 C10 under construction
https://www.facebook.com/groups/248658382003506/

Offline VileZambonie

  • Global Moderator
  • Senior Member
  • *****
  • Posts: 19022
Re: Switching from an A/C HVAC control unit to a non-A/C HVAC inut.
« Reply #2 on: March 11, 2020, 03:58:27 PM »
What you should do is put all of the AC components back in place. Nevertheless, the control unit you have is made to operate the distribution system installed. Leave it as is, there is no reason to change it.
,                           ___ 
                         /  _ _ _\_
              ⌠¯¯¯¯¯'   [☼===☼]
              `()_);-;()_)--o--)_)

74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10

Offline bake315

  • Frequent Member
  • **
  • Posts: 397
Re: Switching from an A/C HVAC control unit to a non-A/C HVAC inut.
« Reply #3 on: March 16, 2020, 06:45:53 PM »
Hello All,

I've got a 78 K10 that originally came with A/C equipped. Since then the A/C components in the engine compartment have been removed (except the evaporator). Which means I have a control unit in the dash does has all the settings for A/C, but they don't do anything.

My question is, can I install a non-A/C control unit and work just fine? One that has the simple heater/defrost settings? Will it plug and play?

Thank You

Are you trying to delete the evaporator from the engine compartment?  If that is the case, I have to imagine that there are others who have done that, and left everything else intact.
• '73 Cheyenne Super C20 454/400 http://forum.73-87chevytrucks.com/smforum/index.php?topic=7672.0
• ’79 Scottsdale K10 350/NP208/SM465 “Oscar” http://forum.73-87chevytrucks.com/smforum/index.php?topic=37885.0
• ’87 Custom Deluxe R30 350/400 “Felix”

Offline JohnnyPopper

  • Senior Member
  • ****
  • Posts: 2557
  • Old Goof
Re: Switching from an A/C HVAC control unit to a non-A/C HVAC inut.
« Reply #4 on: March 16, 2020, 08:21:37 PM »
Unless you're going to restore it (as suggested and I agree) it will work for heat and defrost just fine.

Just ignore the 'other features'.

Why did they strip it out? Never mind...  ::)
1957 Apache 3100 235 Inline 6, 3 on the tree
1973 C-20, 3+3 454 4BBL TH400  Water Injection
1978 K-10, 350 4BBL TH350 NP203 M.M. Part time Kit/Hubs
1980 C-10 under construction