Notices
Series I Tech Garage The place to discuss anything technical about the RX-8 that doesn't fit into any of the categories below.

Heating/Ventilation question

Thread Tools
 
Search this Thread
 
Rate Thread
 
Old 12-22-2008, 09:32 AM
  #1  
RX-Heaven
Thread Starter
iTrader: (6)
 
mazdaverx7's Avatar
 
Join Date: Sep 2008
Location: Vermilion Ohio
Posts: 2,083
Received 175 Likes on 142 Posts
Heating/Ventilation question

on my 05 RX-8 Sport, when i'm using the heat and want the air directed at my feet and press the mode button and direct it that way, i also get air coming out of the defrost vents as well. so i have feet and defrost when i only want feet heat. so i consulted my owners manual first and foremost and it indicated that thats the proper way the air should be being directed in the feet setting. now why do you guys think that is? i realy think that its not a great idea. i for one dont always want defrost when i'm trying to heat my feet. i finally found something i really dont like about my RX-8. its tolerable but mildly annoying. are ay subsequent years different?
Old 12-22-2008, 10:26 AM
  #2  
Zoom Zoom....
 
Silver06's Avatar
 
Join Date: Aug 2007
Location: Western Canada, eh?
Posts: 770
Likes: 0
Received 3 Likes on 3 Posts
You're correct.

The way the system is designed, there is always a little 'leakage' of system air coming out of the defog vents when the selector is on floor position (and vice versa).

If the uncommanded air volume is excessive, you could have a problem with the airflow mode actuator on the driver's side of the blower.

If I were to guess, I'd say the idea is to avoid a huge temperature mismatch between the cabin air, and the windshield glass - could cause fogging under some conditions.

However, this 'feature' seems does seem to be one of those odd design eccentricities of the RX-8 (and Japanese cars in general). Not too many folk consider this a big deal...
Old 12-22-2008, 10:29 AM
  #3  
RX-Heaven
Thread Starter
iTrader: (6)
 
mazdaverx7's Avatar
 
Join Date: Sep 2008
Location: Vermilion Ohio
Posts: 2,083
Received 175 Likes on 142 Posts
its not a huge deal but i guess i'm too used to my RX-7's.... the heat temperature isnt really really warm..more of just a warm air unlike what i'm used to in my 7's with their eye drying heat. engine temps are great. i may look into replaceing the thermostat. i might call the dealer today and order a new one..
Old 12-22-2008, 10:41 AM
  #4  
Zoom Zoom....
 
Silver06's Avatar
 
Join Date: Aug 2007
Location: Western Canada, eh?
Posts: 770
Likes: 0
Received 3 Likes on 3 Posts
Originally Posted by mazdaverx7
its not a huge deal but i guess i'm too used to my RX-7's.... the heat temperature isnt really really warm..more of just a warm air unlike what i'm used to in my 7's with their eye drying heat. engine temps are great. i may look into replaceing the thermostat. i might call the dealer today and order a new one..
mazdaverx7

You obviously have an aftermarket temperature gauge if you know that your engine temps are 'great' (the factory temp. gauge is a 3 position 'dummy' gauge, after all).

If the engine temps are 'great', then why would you think of changing the thermostat?


In answer to your question, though:

There is a known issue with bad solder joints on the circuit board in the temperature controller. This results in no-heat, or erratic less-heat conditions.

Here is the thread (It is a STICKY in the DIY forum) with testing and repair instructions: https://www.rx8club.com/series-i-do-yourself-forum-73/diy-no-heat-repair-heater-control-158200/
Old 12-22-2008, 10:57 AM
  #5  
RX-Heaven
Thread Starter
iTrader: (6)
 
mazdaverx7's Avatar
 
Join Date: Sep 2008
Location: Vermilion Ohio
Posts: 2,083
Received 175 Likes on 142 Posts
thank you for the link and info. no aftermarket gauge, just stock. i was basing my assumption on that gauge. according to that, the temp needle stays where it should and other than that i have no fact to support my engine temps other that the fact that it doesnt overheat or underheat(basing it on the oem gauge). no pressurization of the cooling system into either housing and no overheating due to corroded housings or bad coolant seals or o-rings. at any rate, no loss of coolant and no excessive or under normal engine temps. heat is warm but not as good in previous rotary powered cars.
Old 12-22-2008, 01:53 PM
  #6  
RX-Heaven
Thread Starter
iTrader: (6)
 
mazdaverx7's Avatar
 
Join Date: Sep 2008
Location: Vermilion Ohio
Posts: 2,083
Received 175 Likes on 142 Posts
after a longer drive in the car today and with an ambiant temp of 18 degrees, the heat worked very well and was extremely adequate. i guess i had just not turned it up enough on the fan speed...
Old 12-22-2008, 03:59 PM
  #7  
The devil made me do it
iTrader: (1)
 
DeViLbOi's Avatar
 
Join Date: Jul 2007
Location: Colorado Springs, CO
Posts: 3,708
Likes: 0
Received 2 Likes on 2 Posts
It does take a little bit for the thermostat to open I have found. When it does finally open...you will stay warm.
Old 12-22-2008, 04:40 PM
  #8  
RX-Heaven
Thread Starter
iTrader: (6)
 
mazdaverx7's Avatar
 
Join Date: Sep 2008
Location: Vermilion Ohio
Posts: 2,083
Received 175 Likes on 142 Posts
the 8 really doesnt like this cold ohio weather on first startup. the heat has been realy good today. maybe it was my fault for not dirving the car longer distances. i've put just over 200 miles on the car since i bought it.. i need mooe stick time behind the wheel to explroe the car. its a hard car to stay out of.
Old 12-22-2008, 04:55 PM
  #9  
The devil made me do it
iTrader: (1)
 
DeViLbOi's Avatar
 
Join Date: Jul 2007
Location: Colorado Springs, CO
Posts: 3,708
Likes: 0
Received 2 Likes on 2 Posts
Come hang with us in the spring after we all bring our cars back out. We'll get you goin just fine. :P
Old 12-22-2008, 07:51 PM
  #10  
RX-Heaven
Thread Starter
iTrader: (6)
 
mazdaverx7's Avatar
 
Join Date: Sep 2008
Location: Vermilion Ohio
Posts: 2,083
Received 175 Likes on 142 Posts
i normally wouldnt drive the 8 in the winter but i just bought it and you know how tough it is to stay out of anyways. i'll hang with you guys..you're a bit over an hour away from me.

i would have the 8 in the garage but i'm restoring another 7 and doing a GSL-SE engine swap into it, which isn't at all too plug and play. after that's finished, the 8 will go in the garage. http://www.rx7club.com/showthread.php?t=796342
Old 12-22-2008, 07:53 PM
  #11  
RX-Heaven
Thread Starter
iTrader: (6)
 
mazdaverx7's Avatar
 
Join Date: Sep 2008
Location: Vermilion Ohio
Posts: 2,083
Received 175 Likes on 142 Posts
and don't worry my friend, i'm no stranger to the rotary

my BB 88 TII and my 88 10AE:


85 S:
link to its restoration: http://www.rx7club.com/showthread.php?t=751475


80 Leather Sport:


85 GS i bought wrecked:


85 GS i'm converting to to an 85 EGI setup:








Old 12-22-2008, 08:05 PM
  #12  
The devil made me do it
iTrader: (1)
 
DeViLbOi's Avatar
 
Join Date: Jul 2007
Location: Colorado Springs, CO
Posts: 3,708
Likes: 0
Received 2 Likes on 2 Posts
I grew up 20 minutes east of you in North Ridgeville. We have a 7 person in my other club that autox's with the rest of the guys. We really should move this over to the Cleveland/Akron thread though. I really don't want to **** on your thread about heating ducts and how fukt up they are. :P
Old 12-22-2008, 08:05 PM
  #13  
Grasshopper
iTrader: (1)
 
Jon316G's Avatar
 
Join Date: Dec 2006
Location: Streetsboro, OH
Posts: 6,779
Likes: 0
Received 44 Likes on 33 Posts
Originally Posted by DeViLbOi
It does take a little bit for the thermostat to open I have found. When it does finally open...you will stay warm.
I'll get us back on topic...

Remember... the thermostat opens based on engine/coolant temp.
At roughly 180F the thermostat starts to open and should be fully open at roughly 200F.
If its taking longer (meaning its not fully open by roughly 200F) then you may have a defective thermostat.
It simply opens by melting wax within the cylinder (which is why it starts opening at 180F).
Old 12-22-2008, 08:23 PM
  #14  
RX-Heaven
Thread Starter
iTrader: (6)
 
mazdaverx7's Avatar
 
Join Date: Sep 2008
Location: Vermilion Ohio
Posts: 2,083
Received 175 Likes on 142 Posts
thaks for the info. i noticed that the heat really stars kicking in hot when the engine temp gauge shows the needle close to the half way point, which i can ASSUME is CLOSE to normal operating temp. being that i have been driving the car for longer distances and cranking the heat, i notice how warm it gets....i believe that everything is in working order. i still do not care for the defrost being on when i only want the heat blowing on my feet. other than that my complaint about the lack of heat is all but squashed.
Old 12-22-2008, 08:24 PM
  #15  
RX-Heaven
Thread Starter
iTrader: (6)
 
mazdaverx7's Avatar
 
Join Date: Sep 2008
Location: Vermilion Ohio
Posts: 2,083
Received 175 Likes on 142 Posts
Originally Posted by DeViLbOi
I grew up 20 minutes east of you in North Ridgeville. We have a 7 person in my other club that autox's with the rest of the guys. We really should move this over to the Cleveland/Akron thread though. I really don't want to **** on your thread about heating ducts and how fukt up they are. :P
i'll have to start browsing in the Cleveland/Akron forum and see what you guys are up to in there!
Old 12-22-2008, 08:25 PM
  #16  
The devil made me do it
iTrader: (1)
 
DeViLbOi's Avatar
 
Join Date: Jul 2007
Location: Colorado Springs, CO
Posts: 3,708
Likes: 0
Received 2 Likes on 2 Posts
Thanks Jon...I meant as in it takes longer than other cars I have owned. Doesn't make much sense to me based on how hot a rotary runs...but it is what I experienced.
Old 12-22-2008, 08:27 PM
  #17  
The devil made me do it
iTrader: (1)
 
DeViLbOi's Avatar
 
Join Date: Jul 2007
Location: Colorado Springs, CO
Posts: 3,708
Likes: 0
Received 2 Likes on 2 Posts
Just know that the coolant temp gauge is not all that accurate. If I remember correctly it only knows 3 positions. Cold...normal...and "Oh **** Oh ****...you boiled the coolant"
Old 12-22-2008, 08:46 PM
  #18  
RX-Heaven
Thread Starter
iTrader: (6)
 
mazdaverx7's Avatar
 
Join Date: Sep 2008
Location: Vermilion Ohio
Posts: 2,083
Received 175 Likes on 142 Posts
thats also good info regarding the gauge. i know its not a linear gauge but i was hoping it was more accurate than only a three position gauge...
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Evan Gray
Series I Trouble Shooting
4
11-24-2015 01:00 AM
nferguson88
RX-8 Parts For Sale/Wanted
1
10-06-2015 12:45 PM
urbanvoodoo
RX-8 Discussion
2
09-30-2015 12:41 AM
pjwermuth
RX-8 Discussion
5
09-28-2015 11:36 PM
kody59
RX-8 Discussion
3
09-28-2015 03:43 PM



You have already rated this thread Rating: Thread Rating: 0 votes,  average.

Quick Reply: Heating/Ventilation question



All times are GMT -5. The time now is 07:45 PM.