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I found that my heater just was not working like it should. The blower works fine, the vacuum pump was not constantly running, and I could hear the flap move going from recirculating air to fresh air. I could feel a very slight amount of air coming out of the windscreen and floor vents but it was very hot air. Moving the dial did not make a difference.

So, I assumed the lotus position and started probing around under the passenger side dash for a problem. I didn't think I would find a loose vacuum hose but checked them anyway. Eventually I found the issue.

There are 2 valves that are activated by a plastic arm that rotates when you rotate the dial. One activates the solenoid for the fresh air flap and one activates the flap for heat. The one for the heat had slid up in the holder so that the plunger wasn't being push in far enough. I was able to push it back into the holder and it is working again. If it sides back up I will look at doing something to secure it better. I imagine that the other valve could have the same issue so if you are having problems with the fresh air flap, that couple be something to check.
 

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Cal H
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So, I assumed the lotus position and started probing around under the passenger side dash for a problem. I didn't think I would find a loose vacuum hose but checked them anyway. Eventually I found the issue.
Techspy
You have to assume the Lotus postion in your car as you have an passenger air bag. otherwise in earlier cars we are in a fairly comfortable seated position as we have good access it through the glove box removing the liner a few minutes. If you can take the stereo out, you can access it through there too. It is not advised to push the valves around too much as over time the plastic does age and become brittle.The fragile push on fitting may snap off. If you do that the valves cost $20 in 2002 not sure what they cost now or what the availability is but I got mine from Ray at rd ent. I seem to recall the valve body has a dimple in it that corresponds to an indent in the saddle clamp to help it remain in position so you may have to loosen one of the set screws to safely move it. Even when the set screws on clamp is loose use caution moving valve body while the vac lines attached as you may put a lot of strain on the plunger valve body and if they snap it is not of a type of plastic that can be glued. While in some case the valve has indeed shifted in the clamp as movement as little as 1/16" may alter the functional use of the vent flaps it is more likely that the white plastic tips of the of the plunger has worn or been compressed over a period time. I have done a quick fix in heaters of others by removing the white plastic tip and putting in a shim material inside of the tip and putting it back on the plunger
 

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I too have a heating problem. I will check those out . Great pics.
 

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I have a similar problem in my S4,when you turn the heat on it only comes out of the defrost vents all other vents blow cold air and oddly enough the air condition actually works very well.So tomorrow I will assume the lotus position and see what I see thanks for the tip

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I have a similar problem in my S4,when you turn the heat on it only comes out of the defrost vents all other vents blow cold air and oddly enough the air condition actually works very well.So tomorrow I will assume the lotus position and see what I see thanks for the tip

Sent from AutoGuide.com Free App
Remember.. heat does NOT come out the dash vents regardless of where the rotary switches are.. Yeah, sillly Brits
 

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Wingless Wonder
1988 Esprit Turbo
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Remember.. heat does NOT come out the dash vents regardless of where the rotary switches are.. Yeah, sillly Brits
Not so silly. ;)

"Eliges" always route coolant through the heater matrix, forcing the A/C to cool pre-heated air. :facepalm

So, The Esprit designers were GENIUSES because the heated air doesn't flow through the face-level vents! (Yes, you CAN dehumidify moist air through the defrost/floor with the vents closed.)


:clap:



There is an Elise mod involving a Ford Ranger coolant valve so the driver can make the A/C more effective on the Elise.
 

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Wingless Wonder
1988 Esprit Turbo
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Is It's supposed to be like that? If so are you saying it probably is working like it should
^^^ yes, that's the way it was designed.

Section PD of the Lotus Service Notes shows the airflow path(s).
 
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