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TADTS or is there something wrong. When the fans are on, hot air comes out of my vents with the temperature dialed all the way to cold.

Anyone have this with their one?
 

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Make sure the recirculation (something like that) button is pressed. Yeahhhh also the other button two. Yeaaahhh so pretty much just make sure both those little small circular buttons are lit. Mine did the same. Afterward it blows really cold. I dont know whats wrong with everyone elses Elise but my AC works well.
 

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Is your question specific to when the A/C is on?? If so, I have not idea...

If you are talking about when the A/C is turned off, then I have a thought as I experience this as well....This is only my own personal, unauthorized response, but I think it has something to do with the location of the fresh air inlets and proximity of the radiator. Possibly there's a positive pressure build-up in the front of the car that allows the air to be warmed a bit by the bottom portion of the radiator and that air makes it's way in through the vents even though your temp dial is turn fully blue.. While this reasoning may not entirely be accurate, I'm pretty sure its a TADTS

In this photo, you can see the two vertically oriented mesh-coverd vents in the lower portion of the photograph:



Cheers!

- Allen.
 

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Discussion Starter #4
So from looking at the service manual, there isn't a heater per-se as the hot air comes from the radiator. There is a flap in the system which controls the mix of cold and hot air so it's possible that isn't not closed fully in the "cold" position.

Can anyone else confirm whether hot air should come from the vents when the temperature adjustment knob is in the fully cold position?
 

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Some Possibilities;
1) Low refrigerant
2) Inoperative compressor
3) Boken or slipping drive belt
4) Defective thermostat
Michael
TADTS or is there something wrong. When the fans are on, hot air comes out of my vents with the temperature dialed all the way to cold.

Anyone have this with their one?
 

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So from looking at the service manual, there isn't a heater per-se as the hot air comes from the radiator. There is a flap in the system which controls the mix of cold and hot air so it's possible that isn't not closed fully in the "cold" position.

Can anyone else confirm whether hot air should come from the vents when the temperature adjustment knob is in the fully cold position?
You shouldn't get hot air from the vents with the temperature control knob on cold. That being said, there always seems to be some warm air coming from the vents if you are not using the A/C and just have the temp. set to cold. You may have a stuck flap that is allowing the outside air to pass through the heater core instead of diverting it around as you mentioned. How hot is the air coming from your vents? Can you put a thermometer in the vent and get an actual reading?
 

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From what I was told from my dealer you pretty much have the worse case scenario. If i remember correctly it means that the heater box needs to be replaced because some gears either stripped or broke and the flapper inside of it is not working. He told me this when I brought mine in for the resistor repair. to replace the entire heater box the dealer quote me a few buncks under $2000.00-eek--eek--eek-

I really hope it is something else, but it doesn't sound like it. Keep us informed.
 

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Remove the left front access panel.
Pull off large flexble duct from top of HVAC box
You should be able to see the two flapper valves and determine if they are operating correctly.
 

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Discussion Starter #9
Thanks -I'll take a look at those flapper valves.

So would this also be related to my AC not blowing cold?

Sounds like I need a new heater box. Luckily I've a year left on the warranty.

Luke
 

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There could be many reasons that you don't have cold air blow out of the vents.
As was stated before, if those valves are stuck open then the air is flowing over the heater matrix which is always hot. If they are operating correctly then you must look at other possibilities.
Michael
Thanks -I'll take a look at those flapper valves.

So would this also be related to my AC not blowing cold?

Sounds like I need a new heater box. Luckily I've a year left on the warranty.

Luke
 

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If I have the A/C turned off, and no recirculation, mine blows hot IF I'm in traffic or not moving fast. At speed it blows outside temperature. I guess I should check the flaps, but I'm inclined to think the ambient air is being heated by the radiator when there isn't enough airflow. Did you check your flaps? If so, what'd you find out?
 

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Interestingly enough, the recirculation from the footwell intake(s) can not be turned off. When the recirc. is off, air is drawn from both the footwell and nose intakes. When the recirc. button is pressed "on" the action is to close a flapper valve to shut off the flow from the nose intakes.
 

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Hmm, noticed on the way home from a track day on Thurs that I only had heat. Including when I turned the knob to cold, it blew heat. Not just slighter warmer than ambient air- like the heat was on. It certainly seemed different than the last 4 years I've had the car. I did a search, found this thread, and pulled the access panel, pulled the heater hose...
And it looks like the flapper is working. :confused::shrug:

Any ideas why the flapper would appear to be working and it feels like it is blowing the heat the same as when the heat is set to high? It's always been maybe a touch warmer than the outside air but not too much different. Now just using the vent is like using the heater. :confused:
 

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Mine does it too... but using the A/C fixes that...

the A/C works REALLY well here in Phoenix with the "Viper Mods"

Cools off the car lickity split, no sh1t. The Viper RULES!
 

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There are two possible reasons;
a) One or both of the flapper valves are leaking
b) The A/C is inoperative
Michael
Hmm, noticed on the way home from a track day on Thurs that I only had heat. Including when I turned the knob to cold, it blew heat. Not just slighter warmer than ambient air- like the heat was on. It certainly seemed different than the last 4 years I've had the car. I did a search, found this thread, and pulled the access panel, pulled the heater hose...
And it looks like the flapper is working. :confused::shrug:

Any ideas why the flapper would appear to be working and it feels like it is blowing the heat the same as when the heat is set to high? It's always been maybe a touch warmer than the outside air but not too much different. Now just using the vent is like using the heater. :confused:
 

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yes, the basic mods - drill out the block off panel in the pedal box, insulate the air duct tube, and tape off the intake vents (behind the grill i nthe crash structure) in the hotter seasons. make a night and day difference
 

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didnt read the other replies, but check the flap valve for the heater box.. I had the same problem after using the heater once at night!.. It was miserable the next day in Houston heat..
 

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From what I was told from my dealer you pretty much have the worse case scenario. If i remember correctly it means that the heater box needs to be replaced because some gears either stripped or broke and the flapper inside of it is not working. He told me this when I brought mine in for the resistor repair. to replace the entire heater box the dealer quote me a few buncks under $2000.00-eek--eek--eek-

I really hope it is something else, but it doesn't sound like it. Keep us informed.

I had this problem on my car under warranty. They replaced the box on my car.

Chris
 

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Yes, I visually confirmed the flap valve in the heater core/condenser box moves back and forth with the knob. Yesterday with it being cooler out it didn't seem bad, but if it's 70 or so out it feels like the air blowing out is 100 or so. To hold your hand with fingers in the vent, it is definately well heated air. It is not uncomfortable to hold my hand out the window, it is uncomfortable to hold my hand directly to the vent. It certainly isn't just ambient air. Maybe my problem is somewhat intermittent but I don't understand mechanically how that is possible. I think the flapper even though it is moving is probably just "leaking". That is the only place I can identify that would be the source of my issue.

Pehaps this is a stupid question. If I drill out the block off plate in the car (did it on a friends car but not my own) does air always now blow through there? (guess I can just velcro it back on) Also if I tape off the vents at the front, now where does it take in air to get into the cabin? doesn't the air go from there into the heater box were the flapper valve is and then either across the heater core or AC condenser?

I will try to remember to pick up some insulation for the small streach of flexible hose as well. That actually makes a difference eh? Anybody have a small section to send me, or do I have to buy like 20 feet at the hardware store?
 
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