AC Issue

[USAF Sarge]

2006 Ford Expedition Limited, AC has been working like a champ with no issues.

Today my wife is running errands, and hears a hissing sound. Turns the radio down, hissing still there. Turns the AC off and the noise goes away. Turns it back on and hissing returns and it's blowing hot. She says it coming from the dash, and sounds like it's in the glovebox/passenger side area. Then again noises seem to move base on where you are sitting. She's not home for me to check.

Any ideals what to look at? Bad compressor? Bad....?

We did get some bad winds in the Florida Panhandle today. Lots of debris blowing around, damages to some houses, not ours thankfully.

So don't know if debris hit something, or if the timing is just coincidental and something failed with no warning.

 

[SafariGoneWrong]

Manual or automatic climate control?

 

[USAF Sarge]

I'm assuming automatic as it looks like this. Picture taken from internet.

 

[USAF Sarge]

Manual or automatic climate control?

Messed up my post when I went to quote you. Hit the wrong button. See post above.

 

[SafariGoneWrong]

Long ago I had an 04 EB with automatic climate control and it would start to make a hissing-like sound with reduced and warm airflow after running for a while. I had to shut it down and wait, restart and it would work correctly. Did that when new. Never did figure it out. I suspected a vacuum control issue but that’s speculation. Of course you will want to put gauges on the high and low side but have to have air flowing across the evaporator to get accurate readings, and that may be a problem based on what you’re seeing and hearing. Also, look for wet, oily deposits near all ac connections along the passenger engine bay, and see if you can see the compressor from the bottom for a visual inspection.

 

[SafariGoneWrong]

I have an 06 XLT now, last 11 years, manual climate control. No issues like the 04 EB.

 

[SafariGoneWrong]

 

[SafariGoneWrong]

That’s for the 06 automatic climate control

 

[USAF Sarge]

Long ago I had an 04 EB with automatic climate control and it would start to make a hissing-like sound with reduced and warm airflow after running for a while. I had to shut it down and wait, restart and it would work correctly. Did that when new. Never did figure it out. I suspected a vacuum control issue but that’s speculation. Of course you will want to put gauges on the high and low side but have to have air flowing across the evaporator to get accurate readings, and that may be a problem based on what you’re seeing and hearing. Also, look for wet, oily deposits near all ac connections along the passenger engine bay, and see if you can see the compressor from the bottom for a visual inspection.

Thank you for the detailed and concise answer and explanation. I'll see about getting my aging backside in the engine compartment and underneath it and see what I can find.

I'll have my go to shop check the pressure, most of the guys there went to school with my kids, and take care of me. Well actually they take care of CINC Household, she was the cool mother when the kids were growing up.

 

[USAF Sarge]

Culprit was a failed Schrader Valve.....The AC has no hiss now and is back to freezing cold which is awesome in this Florida Panhandle heat and humidity.