[idk2018]

During the hot , humid weather, I am noticing my exterior windshield has condensation I can only wipe away with the wipers where it returns like rain drops. I have turned off air re circulation , tried defog, and nothing appears to work. Windshield is clean, not spotless. I think it doesn't appear after I treat the windshiled with a decent glass cleaner called Invisible glass.Thoughts?

 

[Fivedoor]

The climate control is blowing cold air on the windshield, chilling it down below the dew point of the hot moist air outside the car, and the moisture in the air is condensing on the windshield.

Keith

 

[Enzeder]

What Keith said. The AC is TOO effective I've had this on other cars too. I haven't measured it, but I would bet the air coming out the vents onto the windshield is ~40°F (maybe less because it's close to the evaporator). The dew point here in swampy Baltimore is ~75°F so the AC can overwhelm the ambient air's ability to keep the windshield above that dew point. I'm not an aerodynamicist, so take this with a grain of salt, but I think the cowl area (base of the windshield) on most cars is a stagnant area for air - I think that's why the bottom part will condense but it doesn't creep all the way up.

I will note that this seems to be handled differently in the Bolt than my old car. In the old car it would only happen when the windshield defrost button was selected - if left in the default setting (Auto), the blend doors would only send a smaller fraction of the cold air to the windshield.

 

[idk2018]

@Fivedoor & @Enzeder thanks for your input. I am hoping my picture actually shows up because the link doesn't appear to work,so trying upload. Today,I had the a/c cranked,it was really humid at 90% [northeast],and the windshield didn't have condensation spread over it,just a little when I parked inside a garage after freeway driving. Bolt EV sat in garages,not air conditioned when I parked. I am puzzled to say the least because dew point is dew point, yet I have no idea when the condensation will reappear under the same humid, hot conditions.

If I didn't wipe the condensation with my wiper,I think it would keep spreading upwards to cover about 60% of the windshield. I read somewhere a coolant leak can cause the exterior condensation.

I am incredibly happy with our Bolt EV's A/C, while the ICE have to save on fuel by opening a window,we can enjoy a cool cabin

 

[Fivedoor]

You probably have auto defog turned on, so the car decides when to direct air to the windshield. When it does you get the condensation on the outside of the windshield, when the car doesn't direct cold air to the windshield you don't get the condensation.

Keith

 

[PhilBo]

What Keith (Fivedoor) said.
Under Personalization Menu> Vehicle> Auto Defog:Select Off or On.
According to the manual: "The system will monitor high humidity inside the vehicle. When high humidity is detected, the climate control system may adjust to outside air supply and turn on the air conditioner or the heater. The fan speed may slightly increase to help prevent fogging. When high humidity is no longer detected, the system will return to its prior operation."

"Auto Defog: When set to On, the front defog will automatically come on when the vehicle is started. Select Off or On."

 

[PhilBo]

"I read somewhere a coolant leak can cause the exterior condensation."
I believe what you're referring to is when the heater core of an ICE car has a coolant leak, the antifreeze mist is blown along with the warm air by the fan. The coolant leaves behind a greasy, cloudy film that is difficult to wipe away without some sort of detergent solution. Also, there is usually a chemical smell present and the film will be on the inside of the windshield not the outside. Keep us updated.

 

[Enzeder]

"I read somewhere a coolant leak can cause the exterior condensation."
I believe what you're referring to is when the heater core of an ICE car has a coolant leak, the antifreeze mist is blown along with the warm air by the fan. The coolant leaves behind a greasy, cloudy film that is difficult to wipe away without some sort of detergent solution. Also, there is usually a chemical smell present and the film will be on the inside of the windshield not the outside. Keep us updated.

Yup. And the smell from the coolant is usually described as "sickly sweet" due to the additives like anti-freeze, corrosion inhibitors, etc.

 

[PhilBo]

Enzedr: You are correct, sir. It is the coolant's sweet aroma and flavor that is appealing (and deadly poisonous) to animals.

 

[GregBrew]

During the hot , humid weather, I am noticing my exterior windshield has condensation I can only wipe away with the wipers where it returns like rain drops. I have turned off air re circulation , tried defog, and nothing appears to work. Windshield is clean, not spotless. I think it doesn't appear after I treat the windshiled with a decent glass cleaner called Invisible glass.Thoughts?

I'll often initially run the A/C through the defrost vents to cool the dash area so it doesn't radiate heat onto my face. The external condensation is a side-effect of this practice. This happens on every A/C equipped car I've ever owned.

 

[Hugh]

During the hot , humid weather, I am noticing my exterior windshield has condensation I can only wipe away with the wipers where it returns like rain drops. I have turned off air re circulation , tried defog, and nothing appears to work. Windshield is clean, not spotless. I think it doesn't appear after I treat the windshiled with a decent glass cleaner called Invisible glass.Thoughts?

I don't encounter this often but when I do, I simply turn the heat up and direct the air to the windshield. Once clear, I lower the temperature and direct airflow in direction(s) that don't include the windshield.

 

[idk2018]

You're using the heat in 90F temperatures? I have tried using the defrost,no difference on the exterior windshield. I am trying to take the advice of other Bolt owners's tips by trying to keep the exterior windshield's temperature equal to,or near the interior.Also parking in shade during the hot days.It hasn't been as bad when I am able to do so. I agree with OP about the Bolt EV maybe having too good A/C ! This is my first BEV,so I am thinking it's part of the efficiency. Accidentally turned on my heated steering wheel one day,it quickly heated up so I know it will work when needed.