Heat on even when temp set at 60F
#1
11-28-2016, 02:53 PM
Heat on even when temp set at 60F
Hi,
I bought a 200,000 mile '08 G35 sedan from my friend and I love it. The car looks and drives great given the miles and age.
I have a minor problem: with A/C off, temp set at 60F, getting outside air, I feel the air flowing through the system is considerably warmer than the outside air. It's as if the heater valve would not close. My A/C is fine, the heater works fine (blows hot air when I set it to 70+F). It is just as if the heat were always on even if I set the temp to 60.
This is a minor problem but I'd like to fix it if possible. I live in Texas, so if the heater never shuts, it is making the A/C work that much harder during our brutal summer.
Is there a heater shutoff valve or some other issue with these cars?
Thank you,
dudlo
I bought a 200,000 mile '08 G35 sedan from my friend and I love it. The car looks and drives great given the miles and age.
I have a minor problem: with A/C off, temp set at 60F, getting outside air, I feel the air flowing through the system is considerably warmer than the outside air. It's as if the heater valve would not close. My A/C is fine, the heater works fine (blows hot air when I set it to 70+F). It is just as if the heat were always on even if I set the temp to 60.
This is a minor problem but I'd like to fix it if possible. I live in Texas, so if the heater never shuts, it is making the A/C work that much harder during our brutal summer.
Is there a heater shutoff valve or some other issue with these cars?
Thank you,
dudlo
#3
11-28-2016, 05:37 PM
#4
11-28-2016, 09:44 PM
I'm trying to understand exactly what you're referring to.
What I think you're saying is that you have the fan on without the A/C on and have outside air coming in instead of the recirculate option?
If that's the case what you explain sounds about right. I'm not sure why freon would matter in your case if the compressor is off since the A/C button is not activated. If I just have the fan on drawing in outside air it pulls in heat from the engine bay which can be pretty warm.
In fact if I am riding along when it's a nice cool day outside I get warm air coming in if I don't have it set to recirculate. At that point the display doesn't show the temp it's set at since the system is off. If I hit the down button to lower the temp all the way down to 60 (if I had it set to 70 and turned it off, if I hit the down temp arrow 10 times it takes the temp down to 60 even though the system is off) the air does get less warm but it's by no means cool. If I turn on recirculate it eliminates that.
If my A/C is on it's always on auto. This is one of the best auto A/C systems I've ever used. If you do use the auto option just keep in mind that the system takes into account the outside temp that shows on the dash thermometer. So when you and I have those 100% humidity and 95 degree days having it set to 70 is going to be colder than if it was 30 degrees outside.
What I think you're saying is that you have the fan on without the A/C on and have outside air coming in instead of the recirculate option?
If that's the case what you explain sounds about right. I'm not sure why freon would matter in your case if the compressor is off since the A/C button is not activated. If I just have the fan on drawing in outside air it pulls in heat from the engine bay which can be pretty warm.
In fact if I am riding along when it's a nice cool day outside I get warm air coming in if I don't have it set to recirculate. At that point the display doesn't show the temp it's set at since the system is off. If I hit the down button to lower the temp all the way down to 60 (if I had it set to 70 and turned it off, if I hit the down temp arrow 10 times it takes the temp down to 60 even though the system is off) the air does get less warm but it's by no means cool. If I turn on recirculate it eliminates that.
If my A/C is on it's always on auto. This is one of the best auto A/C systems I've ever used. If you do use the auto option just keep in mind that the system takes into account the outside temp that shows on the dash thermometer. So when you and I have those 100% humidity and 95 degree days having it set to 70 is going to be colder than if it was 30 degrees outside.
The following users liked this post:
dudlo (12-04-2016)
#5
12-04-2016, 10:21 AM
twitch,
Thank you for your response, you hit the nail on the head:
- this has nothing to do with A/C. The A/C is working just fine. But I like to turn it off on the days the temperature drops below 70F.
- with the A/C off, I set to outside (not recirc). If the outside temp is 60F, I expect the 60F air to blow in. But it is warmer than that (even if my temp is set to the lowest 60F).
I jut checked the service manual. It could be that the "air mix door" is not opening/closing correctly. It is the guy that diverts air to go through heater core. The door works: I get warm air when temp is set to 75 and really hot air when I set the temp to 90. However, it is not closing all the way (when I set the temp to 60).
I had a similar problem with my Volvo 850. The problem was the plastic lever/link that connected motor to the door - it would slip, leaving the door open at all times. This was a know sore spot with these cars; I was just fishing to see if a similar problem is known for G35. Or if there were an easy fix.
Unfortunately, the manual shows that the system is contained in the monstrous "heating and cooling unit assembly". So even if there were some simple mechanical problem, it would be really hard to get to it.
For now, I'll shut up and either run the A/C at all times or open the window. I know, first world problem.
Thank you for your help,
dudlo
Thank you for your response, you hit the nail on the head:
- this has nothing to do with A/C. The A/C is working just fine. But I like to turn it off on the days the temperature drops below 70F.
- with the A/C off, I set to outside (not recirc). If the outside temp is 60F, I expect the 60F air to blow in. But it is warmer than that (even if my temp is set to the lowest 60F).
I jut checked the service manual. It could be that the "air mix door" is not opening/closing correctly. It is the guy that diverts air to go through heater core. The door works: I get warm air when temp is set to 75 and really hot air when I set the temp to 90. However, it is not closing all the way (when I set the temp to 60).
I had a similar problem with my Volvo 850. The problem was the plastic lever/link that connected motor to the door - it would slip, leaving the door open at all times. This was a know sore spot with these cars; I was just fishing to see if a similar problem is known for G35. Or if there were an easy fix.
Unfortunately, the manual shows that the system is contained in the monstrous "heating and cooling unit assembly". So even if there were some simple mechanical problem, it would be really hard to get to it.
For now, I'll shut up and either run the A/C at all times or open the window. I know, first world problem.
Thank you for your help,
dudlo
#6
04-11-2017, 03:07 PM
I had this problem last summer (2015) on my 08MT. I was getting air but even with the setting at 60F, it wasn't cold. Freon wasn't the problem.
Took my car to local mechanic and the work he did was:
- replaced AC compressor and dryer assembly
Parts&labor + tax = $1050
The solution worked and my AC is back to normal. Hope that helps.
Took my car to local mechanic and the work he did was:
- replaced AC compressor and dryer assembly
Parts&labor + tax = $1050
The solution worked and my AC is back to normal. Hope that helps.
#7
04-11-2017, 08:24 PM
I also believe it would be the blend door, in the vast vent channels in modern cars, even if the temp setting is at 60* ( with A/C off) you should get the same air temp as outside, since I run around with mine all the time like that, with windows down. something is not telling so called door to close, all the way or open....