98 5L EB blowing hot air suddenly after three month of use for cooling

[dcdyd]

This suddenly happened. My 98 5L EB has automated climate control. At the beginning of the season, I refilled freon and fixed the blend door in colling position. So the cooling function worked until today when it suddenly start blowing hot air no matter what temprature I set. The last time I used it for cooling was Aug, 25th which was last Saturday.

Today outside temp shot to 92F and I turned the cooling on and found that it blow hot air. After I get home, I opened the front cover and found that the compressor is not engaging at all. I then used air pressure gauge to measure the pressure and found that both low and high pressure is zero - no pressure at all.

Does this mean that all freon leaked in just four days without any symptom. Does this make sense? I would like to understand where I need to start for investigation? Tomorrow it will be 102 here in Minneapolis and looks like that I will be in sauna room when driving back from work to home.

 

[tregare]

if you had to refill the R134a at the beginning of the season (i presume you had no cooling?) then you probably have a leak somewhere.

 

[dcdyd]

At the beginning of the season, the cooling was poor. I found that the low pressure was at about 20 and the compressor was on and off in about 3 seconds. So YES There must be leak somewhere.

But how do I find the leak? Any comments are appreciated.

 

[deweyville65]

With that big/fast of a leak, there will be a massive spot of oil somewhere. Look at your condenser in front of the radiator. A rock could very well have punctured the condenser. Look at all the fittings. It is possible, though not very likely, the evaporator has a leak. I would think you would have smelled or seen oil under the dash if that happened.

 

[SoNic67]

UV leak detector:
http://www.amazon.com/dp/B000IHJXHG...&hvpone=&hvptwo=&hvqmt=&ref=asc_df_B000IHJXHG

 

[tregare]

just remember that if the leak is inside the heater assy uv leak detector probably won't help much. also if you are using uv leak detector you are going to have to charge your ac system up with R134 and get the compressor running for it to do any real good at finding the leak.

 

[benjammin97624]

if there was a leak. and you were to use a uv light to try finding the problem. its unnecessary to have a full charge. there is a dye that the uv light will pick up on. you find an oil or wet spot shine your uv light on it and see if there is a leak or not. best of luck to ya.

 

[dcdyd]

I checked almost everything visually and couldn't find any massive spot of oil. No oil leak on the floor of the garage. The condenser looks good. Actually the condenser is protected by a plastic frame and I couldn't find anything leaking there.

If I fill in R134a with dye, I will need to use a UV leak detector light to see the leak, right?

 

[boominXplorer]

Does your compressor click on and off? If so I would aim toward the blend door.

 

[dcdyd]

The compressor doesn't move at all. I checked the pressure and both high and low are almost zero. The blend door should have no problem because I fixed it at the position for cooling at the beginning of this summer.