a/c dash and panel functions

[willard]

Correct me if I'm wrong but in an AC car there's no fresh air (without ac) venting setting? When HEAT is applied the fresh air goes thru heater core and gets minimal heating even when the lever is in far left position and is directed somewhere... but not thru front vents in dash. Then when you apply MAX AC or AC you get fresh air but climatized and only  thru front vents.

By which orifices the HEAT mode blows air? Certainly not thru front vents that are only blowing cold in (max) A/C mode.


The answer is probably somewhere here but the SEARCH engine doesn't work.

[ShelbyDogg]

For the vent setting you push in the A/C button then pull it back out.  This leaves the fan on and turns off the compressor.  Didn't you read the owner's manual?

Heat blows out of the bottom vent. are your actuators not applying vacuum to the correct pods?

[willard]

Hmm I checked the actuators some time ago and all worked (seemed to). So I thought the valve is the culprit but now I know that it is false.
Maybe the guy assembling the unit after the resto  mismatched the vacuum lines.

Thanks for the tip on venting

[willard]

Well... checke the actuators and all work properly, the box hass been rebuilt with new gaskets and seals. And I still get some heat in A/C, HEAT and even max A/C mode.
I tested both water valves (my old one, and NOS ebay one, I paid $150 for  ) and while SHUT OFF I blown thru all pipes. 3 of them are free flowing, one of them is closed (outlet to the heater I guess). 
Is it normal and you jsut roll down the windows in the summer? venting with fresh air from AC vents would be "cool"

[ShelbyDogg]

I use my vents all the time since my big-block, black interior, big header car, has a hot interior all the time even when the weather is nice outside.  I realized with my convertible that now all the heat is out of the car.

You can still get heat in A/C mode. There should not be any hot water coming through the valve when it is closed all the way.

[willard]

The valve is a bypass type - when shut off it directs water back to the pump, however it doesn not completely isolate heater from cooling water - the return hose from heater has a connection with the hose to the pump . I wish someone has a good valve and can check it blowing thru...

EDIT
Went to garage to check the valve again: when closed no fluid passes thru smaller orifices. The heat must be transfered to the heater via convection?
Which hose larger or smaller is pumping the cooling fluid to the heater? maybe my hoses are mixed?

[willard]

Ok, did a test: started cold engine and waited till the radiator gets warm. Valve shut off. I noticed both hoses to the valve are hot, while the two to the heater are cold. Within 2-3 minutes the RETURN hose (pass side one) from heater tovalve got warmer and warmer while the inlet hose from valve to heater was still cold. 2 minutes more and both valve-heater hoses were mild warm and valve-WP hoses real hot.
So the valve works ok - it blocks the inlet hose but the heat is being transfered via the return hose...

Anyone plugged the valve (I guess the enter from heater return) to stop heat transfer ? Car is 100% stock and I dont want to put another crude valve in the engine bay.

[ShelbyDogg]

I have a couple of valves but I just moved and can't find them to test them. are you sure the return hose is on the correct water pump line? One has more pressure than the other. The correct lines for a 70 water pump had a small hose and a larger hose to match the valve.

As soon as you block it off, you'll need heat. I just used my heater last Sunday AM, Sept 18 in Indiana on a cold morning.  Nice to have heat when you want it even if it is barely moved to the right.

[willard]

I have 2 nipples in the WP housing - larger dia (from valve) in the front and smaller (to the valve via smaller hose) in the back. Picture shows the front one and the smaller one is behind the alt bracket, but you can see the NPT plug just to the right. I guess this is ok ;/