Defroster Efficiency

New 10/04/2004

As the temperatures keep dropping in Michigan, I've noticed my
defroster is not keeping up. It got down to 38 last night and the
defrosters just could not keep up. Front was on just defroster set at
90 with fan at 100% and rear was on, but this does nothing to clear up
the windows. I'm constantly rolling down the windows to clear the
condensation off so I can see. I'm guessing the seals around the
doors aren't what they used to be and the car is not as sealed as it
was once.

Any tell tale signs I should be looking for and ways to conquer this dilemma?

--
Matthew Ponke

_____________________________________________________________________________

Is your A/C compressor working OK? When it was hot did the
system cool well?

Or could the heater core be leaking anti-freeze? This
should be noticeable as a sweet smell of anti-freeze in the
car. You may not notice a drop in fluid level for some
time though.

Finally, is there any heat? If there is no heat, then check
the air control flap or other controls on the HVAC, but even
with no heat, the A/C should take care of moisture on the
windows.

I doubt it has anything to do with the seals on the
doors/windows. More air circulating inside would help
rather than hurt the condensation problem!

Don Mallinson

_____________________________________________________________________________

Looks like you're A/C system is not supplying dehumidified air. Was the A/C
working OK in the warmer weather?

With the car running on Defrost, go out and see if the A/C compressor is
engaged/engaging.

Do you smell coolant? The other slight possibility is that the heater core
is leaking.

The cold spell is only for a few days....supposed to be back in the low '70s
later in the week (per the WDIV weather last night)! It can't get cold
yet.....I have a new lawn going in within the next week or two!! Conversed
with a SHO guy in the UP who said that snow will come any day now, but at
least the Detroit area has another month or two before that happens!

Ron Porter

_____________________________________________________________________________

The AC compressor does kick out occasionally because of the spacer
shim still being on the clutch, so maybe I should try that.

I don't smell any anti-freeze in the car.

The heat works great and I've never had a cooling problem. Maybe I
don't completely understand the defroster system, but its blowing out
very warm/hot air no problem, it just seems the windows just do not
change.

Like I said, it was 38 last night according to the football, and
during a good hour and a half drive, the front & rear windshields were
clear yet the windows were as foggy as if the car had been sitting
over night.

I didn't think I'd have to worry about the AC clutch shim during winter!
Matt

______________________________________________________________________________

It's worth noting (IMHO) that hot air is NOT necessarily better for defogging windows. In fact, the hotter the air, the more moisture it can hold. All that warm, moist air inside a car with 38 degree windows will cause plenty of condensation problems.

I have little to no issues with condensation running on defroster, auto, or vent in the winter with the car set around 70-72 degrees. I see cars all the time in the winter with 6 fogged windows dirinv down the interstate, and I rarely have problems.

If my windows really start to fog in the winter on the interstate, I'll crack the sunroof and the driver's rear window to circulate cold, dry air, then resume with the thermostat set a degree or two cooler.

I have ALWAYS had more problems with condensation with high heat settings than with low, in VW's, Audis, and SHOs.

-John Breen III

_____________________________________________________________________________

Check your Blend Door Actuator.

Rene Carlos Cruz

______________________________________________________________________________

Change your cabin air filter. Did the trick for me.

Mike

____________________________________________________________________________

See Cabin Air Filter for instructions.

U.L.

Contact Information