Solutions for windshield fogging in cold weather?

[acensor]

And I'm sure all of you in cold climates know that unlike regular cars we are hesitant to turn on the heater to drive fogging and even heavvy condensation off the front windshield.

Turning on the air conditioning is often quite effective in clearing the window and does use less battery and the heater, but not much fun when it's already cold in the car, and still significant battery cost if on a longer drive without a lot of Rr margin.

I have tried Rain-X anti-fog stuff.
Results are equivocal, and kind of weird. Sometimes it helps a great deal of the times the rain X part of the window seems to fog even more.
And when it is not cold the rain X seems to show a light .....not terrible , but annoying.... Bit of hazy streaking when driving into the sun.

I experimented a little bit with trying to meticulously clean the glass before applying the rain X.with putting on lighter layers of the rain X or heavier layers, etc.
As I say with equivocal results.

I can say that treating with rain X is often better than nothing in terms of anti-fog, but not really happy with it,and yesterday found myself having to turn on the heater as The only way to get decent vision.

Hey, any thoughts more solutions?

 

[jray3]

My back seat is usually full of mouth-breathers, so I just keep the air flowing over the windshield, and if it's wet out, as it usually is around Seattle, I keep that compressor running on the lowest fan setting and neutral temperature. That drops out the moisture before it hits the glass. Main thing is an ounce of prevention- never getting to the point of trying to overcome heavy condensation on the glass.

 

[NeilBlanchard]

It would be awesome if someone could try installing a direct heating defroster kit to the windshield!

This would save a lot of energy, and work more quickly than the stock defroster.

 

[fjpod]

Even with 2 or 3 people in the car, I am usually successful keeping the windows clear by simply running the fan on low with no heat or AC. Fresh Air, not recirculated.

 

[jsantala]

I've stuffed an old pair of kids' pantyhose with silica cat litter. It absorbs moisture quite nicely. Best if spread across the dash.

See https://www.dropbox.com/s/oc6515cz37m0pc5/2014-12-12%2009.18.02.jpg?dl=0

 

[Barbagris]

My 2c:

Detergent/soap. Applied inside the windshield until clear.

Test on half windshield:

Worth a try ... it's cheap!

 

[acensor]

Even with 2 or 3 people in the car, I am usually successful keeping the windows clear by simply running the fan on low with no heat or AC. Fresh Air, not recirculated.

Why fresh (outside) air? Shouldn't that depend on how cold and how damp that outside air IS?

 

[acensor]

My 2c:

Detergent/soap. Applied inside the windshield until clear.

Worth a try ... it's cheap!

Thought of that. Is a traditional solution (pardon the pun).

Did you make a very dilute solution of dish detergent? How dilute?
Wiped on lightly with clean rag?

 

[Don]

Even with 2 or 3 people in the car, I am usually successful keeping the windows clear by simply running the fan on low with no heat or AC. Fresh Air, not recirculated.

Why fresh (outside) air? Shouldn't that depend on how cold and how damp that outside air IS?

That method works best for me too. I think using the windshield setting with outside air on low fan blowing across the inside of the glass equalizes the temperature and prevents the warmer, more moist inside air from condensing on the glass. Anyway, whatever the 'science' of it actually is, it works!

Don

 

[PV1]

I always leave fresh air go to the windshield with the fan off when it's just me, but I have to turn the fan on one click at least when there's other people. I may start trying with the heat on one click, because with no heat the car gets cold fast. I'd love to find a solution that doesn't require letting the cold in. I may try the soap solution.

Piece of advice, don't use the stock washer fluid when it's below freezing. That stuff turns to instant ice.

 

[peterdambier]

Hot and wet wife. As soon as she comes in her side of the car starts fogging.

In summer that is no problem, opening the windows a little bit does it. In winter when it is cold and wet outside that turns into desaster. Getting down from the mountains to the Rhine Valley is like hitting a brick wall. Suddenly all windows turn opaque. Warm and wet inside but cold outside, condensation ...

A/C is the best remedy. Heat only helps a little bit but we need it nevertheless if we dont want want to die from freezing.

Downhill heat, A/C and maximum fan is not a problem because we need to kill energy from regen to be able to do breaking.

Our way home is another problem. Insulating doors, back and the front lid did help a lot.

We have seen a lot of gassers today facing the same problem. The drivers kept their windows open to be able to see.

Not exactly "frette" but quiet cold nevertheless. -12 Celsius or 10 Fahrenheit last night. I am glad I left a cable dangeling out of the window and a 2 kW heater and fan inside. I use the cable for both charging and heating. Changing the plug to the heater will unfreeze my mains cable lying in the snow :lol:

Charging in the snow is a mess but plugging in my cable and half an hour later digging "Snowwhite" out of the snow is almost fun. Other drivers have a lot more trouble and are no faster. Yet another half an hour and the car is nice and warm.

I have cut a peace of foam tubing that is normally used to insulate heat pipes. Open a slit and put it over the window. Stick your cable out and close the window again. Looks like the car was made that way. For charging I put the snout with the J1772 out as well and stick it into the charge port. The brick stays warm and dry inside the car. When finished charging I run the heater for a short time until I can open the window to pull the J1772 cable inside and close again but I unplug the mains cable of coarse.

Cheers
Peter and Karin

 

[PV1]

Anybody try redirecting the coolant loop for the motor and inverter to the heater core? I've watched on OVMS my motor temperature easily getting up to 70-80 degree Fahrenheit range in the first mile of driving. I've tried watching it all the way to work, but there's a spot where cell coverage hiccups and the module stops communicating for a bit, screwing up my readings.

Anybody know of a wireless thermometer probe that I could tape to the coolant lines?

 

[fjpod]

70 to 80 degree water isn't going to give you any appreciable heat.

 

[PV1]

Yeah, but that's with cold air going through the radiator chilling it at a constant 48 mph on a level road. If the coolant is re-directed to the heater core, bypassing the radiator altogether, there is less heat transfer, so the coolant can get a little warmer, and therefore give you warmer air from the vents. Tooling around the city, my motor can hit 110°+ rather easily. I'm not going to be cooking the cabin with this, but hopefully make the car a little warmer without running the heater.

Either way, it'd be warmer than unheated fresh air coming in. Since some of us (myself included) modify our charging routine so that the car finishes charging about an hour or so before we leave, the charger already has the entire loop preheated.

Having charger and motor temps in CaniOn would be a plus. The car reports them since OVMS has them. I'll see if I can't find a temperature probe at the store and install it on the water line for the time being. I might also try blocking the front grille while watching the temps and driving around.

Now for the disclaimer. Attempting these modifications may cause your i-MiEV's electronics to overheat, causing damage. This mod is only to be performed if you understand the risks and take full responsibility for your actions. I can't be held responsible.

 

[acensor]

Anybody try redirecting the coolant loop for the motor and inverter to the heater core? ......
.....Anybody know of a wireless thermometer probe that I could tape to the coolant lines?

Lots of wired and wireless ones all over the web.
Like this for only $3 :
http://www.ebay.com/itm/Mini-Digital-LCD-Display-Thermometer-Temperature-Temp-Sensor-/280938071097

Even got one at local radio shack once.

 

[PV1]

So, I duct taped a sensor to the coolant pipe leaving the motor and put a piece of foam insulation around it (thin stuff, same as I used for the doors), and I've been watching the temperature while driving and charging.

Driving on level, there isn't much increase in temperature with the radiator unblocked (as there shouldn't be). If I just finished charging or pre-heating, then start driving, the temperature might even drop a few degrees. However, I do notice an increase when driving on hilly roads, but really see an increase on the highway. Coming home last night after 20 miles of 60-65 mph on the highway with an ambient temp of 37 F, the coolant was up to around 70 F. I think it peaked around 80 F while parked, though I'll have to check the thermometer. The interior with pre-heat was around 50 F.

On Saturday with an ambient temp of 0 F, the coolant loop was around 35 F on the highway at 60 mph. Interior temp was 20 F.

If I were to install shutters in front of the radiator or bypass the radiator, that would allow the coolant to reach higher temperatures. The fact that I was able to go 40 F over ambient at 60 mph with full airflow through the radiator leads me to believe that there is an appreciable amount of waste heat available for recovery. I was working on the design for such a system.

https://www.dropbox.com/s/6go1xmz0nkah0v0/i-MiEV%20waste%20heat%20recovery.png?dl=0

Would need to find a way to shut off or disable the electric heater, but allow the water pump to still function with the temp knob in the red. Have an automatic pump kick on if the coolant gets too hot and send it to the radiator to cool it. It would need two temperature settings, a lower setting for summer and a higher setting for winter.

 

[jray3]

If I were to install shutters in front of the radiator or bypass the radiator, that would allow the coolant to reach higher temperatures. The fact that I was able to go 40 F over ambient at 60 mph with full airflow through the radiator leads me to believe that there is an appreciable amount of waste heat available for recovery.

There's a risk of losing sight of the forest for the trees. I'd at least want to consult a chart of motor efficiency losses as temperature climbs. The system described risks not only motor or inverter damage from accidental overheating, but could also create a negative feedback loop by reducing motor and inverter inefficiency in the pursuit of 'free heat'. The net returns could be marginal or even negative.

 

[acensor]

My 2c:

Detergent/soap. Applied inside the windshield until clear.

Test on half windshield:

Worth a try ... it's cheap!

Looks good!

How about some details?
What dilution did you apply?
Wipe on with sponge or what?

 

[Barbagris]

Looks good!

How about some details?
What dilution did you apply?
Wipe on with sponge or what?

The last time, a little dishwashing detergent on a clean cloth and rub until transparent.

But you can try other soaps!

 

[tigger19687]

I am testing the dish-soap now. Rainx-fog wipes didn't really work much.
I did dish-soap, very light coating on Passenger side windshield where the wiper doesn't hit and on the drivers window.

It is going to be rainy tomorrow so I will try it out and see if there is any issues.
Only thing I can see so far is that the sun may give that weird glare off it.


Anyone else get this to work besides Baragris?