Hey guys. I am new to this forum. I have a 2008 Chevy Suburban 1500 LT that we have owned for 3 years or so here in Arizona. The past 3 years our AC system has worked as it should.
So about 2 months or so ago when it started getting hot here we began to notice we would lose air flow through the vents when the AC was on. Not knowing what I was dealing with I turned to Google. I replaced the Mode Door Actuator thinking that the door was getting stuck between the different vents making me lose air flow. I had turned the car off once or twice things would reset and I would get air flow again.
I did more reading after the problem persisted and found some TSB's that described a similar problem being cause by low voltage output. I had the battery tested, and even swapped out the alternator to a higher amp. alt. Problem persisted.
I had read that the blower motor itself could be going out, so I threw a blower motor at it. While doing that I inspected the evaporator and saw nothing blocking the evaporator to cause it to freeze up.
One road trip to Tucson I pulled over as soon as air flow diminished and looked under the hood to find the accumulator frozen. Come to find out the evaporator freezes over when the accumulator freezes.
I live in a small town. Choices of services are limited. The shops that have been recommended have looked it over and have supposedly checked pressure and recharged to spec. Accumulator still ices over, but only on road trips going down the highway. Was recommended to replace low pressure cycling switch on the side of the accumulator. I have done that and it is still icing over. I have noticed that the compressor is not cycling. It is either on when it is on... or off when it is off. One shop told me today to raise the temp up on my dial just a little to see if the problem goes away. I did that and drove for about 10-15 miles down the road and it worked normal. I am not sure that was enough time to have it freeze over.
Hopefully all of this makes sense. Please give me ideas on where to look or what to mention to these shops.
So about 2 months or so ago when it started getting hot here we began to notice we would lose air flow through the vents when the AC was on. Not knowing what I was dealing with I turned to Google. I replaced the Mode Door Actuator thinking that the door was getting stuck between the different vents making me lose air flow. I had turned the car off once or twice things would reset and I would get air flow again.
I did more reading after the problem persisted and found some TSB's that described a similar problem being cause by low voltage output. I had the battery tested, and even swapped out the alternator to a higher amp. alt. Problem persisted.
I had read that the blower motor itself could be going out, so I threw a blower motor at it. While doing that I inspected the evaporator and saw nothing blocking the evaporator to cause it to freeze up.
One road trip to Tucson I pulled over as soon as air flow diminished and looked under the hood to find the accumulator frozen. Come to find out the evaporator freezes over when the accumulator freezes.
I live in a small town. Choices of services are limited. The shops that have been recommended have looked it over and have supposedly checked pressure and recharged to spec. Accumulator still ices over, but only on road trips going down the highway. Was recommended to replace low pressure cycling switch on the side of the accumulator. I have done that and it is still icing over. I have noticed that the compressor is not cycling. It is either on when it is on... or off when it is off. One shop told me today to raise the temp up on my dial just a little to see if the problem goes away. I did that and drove for about 10-15 miles down the road and it worked normal. I am not sure that was enough time to have it freeze over.
Hopefully all of this makes sense. Please give me ideas on where to look or what to mention to these shops.
