A/C blows hot after driving for an hour

[cullyhog]

My 06 Vue, V6 A/C starts out fine. After about an hour on the road, the a/c starts slowing getting warmer. It never gets hot but blows cools to warm. It has 35K miles on it. The Saturn dealer replaced a "temp valve"? last year and it has worked well up until last week. They can't find a problem.
Any ideas? The service writer said the compressor is freezing up and to shut it off for 30 minutes then cut it back on! That won't work driving from Atlanta to Florida in 95 degree weather.
thanks

[cullyhog]

Just an update on the A/C. I got the Vue back from the dealer all repaired.
The report said: "Tech installed heat conductor compound on the EX Block Sensor". I've tried to look up an EX Block Sensor and can find no such animal. I guessing they applied Heat Sync compound to a sensor to dissappate heat.
I'll find out next trip.

[far2grumpy]

Originally Posted by cullyhog

Just an update on the A/C. I got the Vue back from the dealer all repaired.
The report said: "Tech installed heat conductor compound on the EX Block Sensor". I've tried to look up an EX Block Sensor and can find no such animal. I guessing they applied Heat Sync compound to a sensor to dissappate heat.
I'll find out next trip.

I browsed through the FSM (up and including 05 Vue) for references to heat conducting compound.

See the attached procedure to replace the compressor thermal protective (TPS) switch. A key step is to apply thermal conductive sealant to the TPS.

Do you suppose the "temp valve" they replaced last year was the compressor TPS switch? And, is it possible they failed to apply thermal conductive sealant as directed?

Incidentally, its in the high 90's in Iowa ... too hot to go outside ... and I'm full of conspiracy theories (I also think Lee Harvey Oswald was not single shooter ).

[far2grumpy]

Just in case you really wanted to see the attachment:

[cullyhog]

I looked up my old ticket and they changed the expansion valve temperature sensor and lubed sensor per bulletin 2001048.
Thanks for your info. They may have done exactly what they said or they put something down to close the ticket. The same tech worked on it both times. I guess time will tell.
You've been a big help. Warranty is about out on the Vue so I guess I better be getting a tech manual.