Air conditioning intermittently blowing warm air

intermittent

#1

We have a 2010 honda Odyssey and we are experiencing some air conditioning problems. The ac went out on us about 6 months ago so we had the compressor replaced. A few weeks after that the ac would intermittently start blowing warm air. We took it back to the shop and they noted that the compressor was shutting off for some reason. They replaced the compressor again, but we are still experiencing the same problem. It will just start blowing warm air for about 15-20 minutes then it will start blowing cold again. This will happen about once every 2-3 days. We replaced the relay, but that didn’t help. They have checked for leaks, recharged the compressor and checked the freon and still nothing. We’re are pretty much at wits end and are getting desperate.


#2

Next time it does it, check and see if the compressor is running. If it is, it could be the blend door. If it’s not running the it could be the high or low pressure switch.


#3

If there are 2 fans by the radiator, check that they both turn on when you engage the ac, if not my best guess you have a bad fan, and because the cooling system cannot keep up ut shuts down the AC. My gues is it happens when you come to a stop, driving slowly, like in a fast food pickup lane. It could also be the system not holding pressure, due to a pressure leak or bad radiator cap. See if you can replicate the situations under which it happens.


#4

When this happens, turn off the air conditioner for five to ten minutes and then turn it back on. If it starts pumping out cool air, the problem may be that the evaporator coil is icing up and blocking the air flow. Have the serviceman check the refrigerant pressures.


#5

Well the latest is that they replaced the hi/low pressure switch. One week later it started blowing warm air again. This will happen for anywhere from 5 minutes to 30 minutes and then it will start blowing cold again.


#6

Well the latest is that they replaced the hi/low pressure switch. One week later it started blowing warm air again. This will happen for anywhere from 5 minutes to 30 minutes and then it will start blowing cold again.


#7

When it blows warm air you need to check to see if the compressor and fans are running.


#8

The problem might be with the expansion valve.

http://www.rockauto.com/catalog/moreinfo.php?pk=1003222&cc=1444550

If the expansion valve is malfunctioning when it gets hot and sticks, the high side line pressure will build to a point where it causes the high pressure switch to cut power to the compressor. Then once the expansion valve cools back down it functions again.

Any time I hear a Honda having AC problems like you describe, and the rest of system seems to be in order, the expansion valve is the first thing I suspect.

Tester