Warm A/C when Idle

[scorpionsix]

Hello All,

I have a question regarding A/C Temperatures during Idle in warm climates (Phoenix, Arizona). I have a 2005 Prius with 63K miles and the A/C works GREAT when commuting 30 miles one way in the HOV lane. However when driving in the city from light to light, I notice that the A/C warms up almost like it isn't working.

Has anyone experienced this and if so is it normal? I am considering taking it too the dealer, but wanted to consult with other owners first.

Thanks!

[richard schumacher]

Not normal. Does it get cold if you set the temp lower? If not then it's off to the dealer.

[scorpionsix]

Figured as much -- Even when the A/C is set to Auto and Max cold and outside temp(s) are around 90 + or - 10 Degrees the inside cabin temperature feels like a warm 78 degrees (when sitting at a stop light)...

[richard schumacher]

Bummer.

An unfortunately common failure mode is puncture of the A/C radiator by road debris. The undercarriage is rather open. It may be prudent to add some wire mesh or expanded metal for protection.

[racerbob]

Dealer will most likely find a condenser fan that is not working. AC will be ok when moving because there is airflow over the condenser. When you stop, there is no heat transfer. Refrigerant level should be fine if it cools when you start moving. You might want to check to see if the condenser (in front of the radiator) is plugged with insects or rocks/sand. Check for a blown fuse before making the trip to the dealer.

[scorpionsix]

Thanks for the helpful information!

Say it was damage to the AC condenser or radiator, and I purchased the Premium Extended Service warranty - I know this is all speculation, but would you imagine that this would be covered under warranty {or} since it happened while I was driving would I be responsible?

[Patrick Wong]

If the damage was due to a road hazard, I would not expect the warranty to cover the damage. However your auto insurance might cover it as a comprehensive claim.

I think that racerbob is on the right track. Try turning on the A/C when the car is READY, and see if at least one radiator fan (out of two) is running. If neither fan is operating, that proves his guess is correct.

[scorpionsix]

Follow Up:

After getting a clean bill of health from the Dealer, with the exception of the Freon being a little low, the A/C was found to be in good working condition with no leaks.

A week later, I have found that if I turn off the Auto AC, and set the fan speed to medium or lower, I get a much cooler temperature in the warm Phoenix AZ afternoon heat.

I can only assume that when the AC Fan is running at a lower speed it is not working as hard in Auto AC mode?? Temperature wise, the lower the fan speed, the cooler the temperature???

Thanks for all the helpful suggestions!

[jayman]

Originally Posted by scorpionsix

After getting a clean bill of health from the Dealer, with the exception of the Freon being a little low, the A/C was found to be in good working condition with no leaks.

I'd wonder about that diagnosis. My Prius is 4 years old and the A/C is still ice cold.

A very slow leak can be hard to find. The most likely culprit is the condenser, it picks up a lot of road debris

[racerbob]

Also using the recirculate mode will give you colder vent temps.