Interior heat not working.
Thread Starter
Instructor
Joined: Dec 2009
Posts: 109
Likes: 0
From: Nassau co. NY
Interior heat not working.
Hi all,
Here is what we have... The in-line heater valve is in the open position and it functions when vacuum is applied (closes), The heat/a/c control worked when tested out of the car a few months ago (vacuum is applied to proper hoses when selector changed, and car temp gauge is running at about 190 degrees (it is about 40 deg today). I think the temp selector is working. I checked it when we put the car together, but I have not verified it all together.
We still get just cool air coming out the heater ducts. The strange thing is, when I reach my hand up to the heater hose in between the valve and heater core, It is cool. There is no vacuum at the line to the valve, and even when I unplugged the vacuum line, no change..still cool.
Has anyone had any problems like this? I am ready to pull off the heater hoses from the engine and see if there is blockage. The heater core was completely free and clear (I blew it through and the heater hoses are completely new).
thanks for any assistance,
Greg.
Here is what we have... The in-line heater valve is in the open position and it functions when vacuum is applied (closes), The heat/a/c control worked when tested out of the car a few months ago (vacuum is applied to proper hoses when selector changed, and car temp gauge is running at about 190 degrees (it is about 40 deg today). I think the temp selector is working. I checked it when we put the car together, but I have not verified it all together.
We still get just cool air coming out the heater ducts. The strange thing is, when I reach my hand up to the heater hose in between the valve and heater core, It is cool. There is no vacuum at the line to the valve, and even when I unplugged the vacuum line, no change..still cool.
Has anyone had any problems like this? I am ready to pull off the heater hoses from the engine and see if there is blockage. The heater core was completely free and clear (I blew it through and the heater hoses are completely new).
thanks for any assistance,
Greg.
Thread Starter
Instructor
Joined: Dec 2009
Posts: 109
Likes: 0
From: Nassau co. NY
Greg.
Melting Slicks
Joined: Mar 2005
Posts: 2,838
Likes: 10
From: Austin TX
You've probably already inspected, but many simply bypass the heater core by connecting the ends of the two hoses. This is done to reduce cabin heat in the summer or to delay repairing a leaky heater core.
Or, maybe there's another add-on shut-off valve that somebody custom installed to reduce cabin heat.
Double check.
Or, maybe there's another add-on shut-off valve that somebody custom installed to reduce cabin heat.
Double check.
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Safety Car
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From: Southeast, Tennessee
St. Jude Donor '09 thru '26
based upon the fact that you say the hose from the engine to the valve isn't hot, i would suggest that perhaps it is blocked in some way (or kinked to stop the flow of water). that hose (regardless of valve position should be the same temp the water in the engine block. the lack of a thermostat in 40 degree weather would also contribute to that hose being less than real hot.
Last edited by srs244; Dec 3, 2010 at 02:00 PM.
Thread Starter
Instructor
Joined: Dec 2009
Posts: 109
Likes: 0
From: Nassau co. NY
based upon the fact that you say the hose from the engine to the valve isn't hot, i would suggest that perhaps it is blocked in some way (or kinked to stop the flow of water). that hose (regardless of valve position should be the same temp the water in the engine block. the lack of a thermostat in 40 degree weather would also contribute to that hose being less than real hot.
Thanks everyone,
You all make very valid points, but , I should mention, Everything has been dissassembled and gone through or replaced. The valve was in the open position and tested with a mityvac and operated correctly when vacuum was applied (causing valve to close). The heater hoses are brand new and not kinked anywhere. It has a new AC 180 thermostat and temp according to guage is around 210, but with an infrared point and shoot, it says 185-190 at the thermostat housing.
I guess the next move will be to pull of the hose and check for flow.
Thanks all,
Greg.
Le Mans Master
Joined: Oct 2006
Posts: 7,123
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From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
You might also pull both hoses off the heater core and hook the garden hose to one side. Also a possibility the core is plugged up internally. (I hate to say that, but....)
Thread Starter
Instructor
Joined: Dec 2009
Posts: 109
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From: Nassau co. NY
I am just wondering, in the attached picture, the manifold fitting is the output, while the other green circled fitting on the side of the water pump is where the return is?? Is the yellow circled plug only for a temp sending unit and not a return?
Tomorrow I will pull off the return hose at the pump and see if I still get anitfreeze coming out while running...I doubt it or I would have heat. I noticed when I pulled the hose off the manifold fitting, there seemed to be air coming out before the antifreeze. with the angle of the fitting pointing upward, how do you bleed the air out of the hose? I though it just got flushed out and eventually made its way to the radiator and bled out on it;s own.
Greg.
Last edited by 69VetteAngel; Dec 4, 2010 at 10:28 PM. Reason: forgot picture attach
