Evaporator freezing up
 

I have a 2004 V6 EX coupe and on a recent road trip noticed that the amount of air from the vents progressively got worse and worse. It was still very cold, but even turning up the fan did not significantly increase the volume of air. While at a rest stop with the engine off, I noticed that the amount of condensate dripping from under the car was *much* more than usual. Upon starting the car and turning the A/C back on, I once again had good airflow, but the same issue slowly returned. So it's obvious the evap is freezing up.

I'm usually able to feel the compressor cycle while driving and I believe I still can, but it wasn't when I opened the hood and had a look. The compressor does turn off when I turn the A/C off, so I'd say the relay is ok. When the A/C is on, the air is VERY cold, more than I remember it ever being, so would this likely mean:

-the R134 level is ok, and
-the compressor is simply not cycling?

Would this likely point to the evap temperature sensor? Incidentally, I did try to do the HVAC diagnostic but didn't have any luck.

(HVAC Code(s) - Honda Accord Forum - Honda Accord Enthusiast Forums)

I tried what is in both posts 1 and 2, but it didn't seem to display codes like explained. Not that this necessarily would point to the A/C's issue. Has anyone had luck trying this?

Re: Evaporator freezing up
 

Update: The compressor is cycling. I checked it in better lighting. No problems on the way home from work, but it's not nearly enough time to know.

Re: Evaporator freezing up
 

Sounds like time to get a set of gauges and get the high and low side readings...there is a bit more to it as you will need to know the temps when taking the readings.

A low charge in the AC system could show as the issue you are describing but you need to get the readings - high and low - before doing anything.

Re: Evaporator freezing up
 

I'm familiar with residential condensers freezing when low on freon,not sure on automotive applications.Another thing to check would be the cabin filter to make sure it isn't restricting airflow.

Re: Evaporator freezing up
 

I have read that low charge can cause this, but I don't understand how. I'm not doubting it, it just seems counter intuitive. Apart from it seemingly cooling even better when having a low charge, the big thing that gets me is regardless, why wouldn't the evap temp sensor cut the compressor off before it freezes?

Has anyone used the Harbor Freight gauges (http://www.harborfreight.com/ac-r134...t-60806.html)? I haven't messed with A/C repair before, but have fixed numerous other things so this can't be difficult.

Re: Evaporator freezing up
 

"All the science I don't understand, it's just my job five days a week" - great song IMHO.

Anyway, the "harbor freight" gauges are pretty good.

You'll want to do some reading on automotive AC systems and how to understand what the the pressures are "telling" you and factors that can throw them off.

Re: Evaporator freezing up
 

Hello, i have the same problem as you, how did you resolved your car problem? Mi honda pilot it freezes after 30 minutes driving in highway, air restricted after the AC is turn off then after 10 minutes turn on it works any help will be appreciated

Re: Evaporator freezing up
 

Oh wow, I haven't been to this forum in years.

I no longer have that car and never resolved it, but this type of thing happens when the refrigerant is low. This happened to my residential A/C too and was resolved by recharging it.