A/C freezing up on long trips
A/C freezing up on long trips
I have a 2010 4.0 V-6 and the a/c will start to freeze up when I take it on a trip of 50 miles or more. Around town it usually works very good, almost too good. When I cut it off the amount of condensation under the truck is unbelievable. The amount of coolant seem right and since it's still under warranty I take it to the dealer and they can't or won't figure it out.
Any ideas out there?
Any ideas out there?
If it is Under wty. Take it to dealer. Car AC units should have a temp sensor that drops voltage to clutch on compressor when it reaches temp set point. However if the cabin is not getting too cold I would suspect some sort of a restriction in the high side of the refrigeration circuit.
Odds are the evaporator is dirty and needs a rinse.
MAX recirculates are in the cabin, it is designed to cool quickly. For longer periods regular AC should be used as it draws in fresh air.
Using regular AC it should allow hotter air and keep it from freezing. Another thing to try is keep the fan speed up, if you get cold mix in some heat. Again this is only available in regular ac.
MAX recirculates are in the cabin, it is designed to cool quickly. For longer periods regular AC should be used as it draws in fresh air.
Using regular AC it should allow hotter air and keep it from freezing. Another thing to try is keep the fan speed up, if you get cold mix in some heat. Again this is only available in regular ac.
If a switch is bad it would be the high pressure not cutting off the compressor. The low pressure turns the compressor on when the pressure drops or when the accumulator is running low on compressed gas.
Whatever the issue we can only guess as we cant touch the truck.
Whatever the issue we can only guess as we cant touch the truck.
You're most likely just a little low on refrigerant. Less refrigerant = less pressure, lower temp of the coil causing more condensation to freeze to the ac coil.
Low pressure switch shuts off the compressor, high pressure switch turns it back on. Could be a faulty low pressure switch as well causing the temp of the coil to drop as well.
They should be able to find out the problem fairly easy just by putting a set of gauges on the system and seeing what pressures it's running at.
Low pressure switch shuts off the compressor, high pressure switch turns it back on. Could be a faulty low pressure switch as well causing the temp of the coil to drop as well.
They should be able to find out the problem fairly easy just by putting a set of gauges on the system and seeing what pressures it's running at.
I had this problem on an 89 Ranger. There was a switch near the firewall (maybe on it) that could be adjusted to cycle the A/C to keep it from freeing up. I don't know if it was sensing high or low pressure to kick the A/C compressor out. I was able to adjust it so the A/C would not ice up and block the air flow. I don't know what the equivalent is on newer Rangers but I suspect it is not adjustable.
On the last trip I took to Kansas in April, I had a similar problem with my 02 Ranger coming back home after having the A/C serviced there. I don't know if it got overcharged but it didn't do this before I had it serviced, it just did not cool quite as good as it should. I have not looked into it because I found when it freezes up, I just have to turn the A/C compressor off for a minute or two, the ice melts and the air starts blowing again for another hour or so.
I have also found recently that my 02 Ranger A/C compressor sometimes will not kick in if I turn it on while driving down the road. If I turn it on at idle will kick in. I don't understand that but I may have a A/C relay that is acting up. Maybe that has something to do with it freezing up too. The A/C relay went out under warranty and was replaced by the dealer. I may try replacing the relay.
On the last trip I took to Kansas in April, I had a similar problem with my 02 Ranger coming back home after having the A/C serviced there. I don't know if it got overcharged but it didn't do this before I had it serviced, it just did not cool quite as good as it should. I have not looked into it because I found when it freezes up, I just have to turn the A/C compressor off for a minute or two, the ice melts and the air starts blowing again for another hour or so.
I have also found recently that my 02 Ranger A/C compressor sometimes will not kick in if I turn it on while driving down the road. If I turn it on at idle will kick in. I don't understand that but I may have a A/C relay that is acting up. Maybe that has something to do with it freezing up too. The A/C relay went out under warranty and was replaced by the dealer. I may try replacing the relay.
Just brought it home from the dealer, it's supposed to be 98* here tomorrow so it will get a workout. If it's fixed I'll reveal the answer. It better be they burned up 3/4s of a tank of gas test driving it.
You guys did hit all around it.
You guys did hit all around it.
Second day, temperature in Memphis was 99* yesterday and 97* today, no troubles, a/c workin' like a champ and I put 75 miles on the truck yesterday and at least a 100 on it today.
Ford said it was the compressor's cycling switch.
A big plus today was gas at $3.38 a gal. in Hernando, Mississippi.
Ford said it was the compressor's cycling switch.
A big plus today was gas at $3.38 a gal. in Hernando, Mississippi.
AC, refrigerators and freezers all work the same way
You compress a fluid/gas which gets it HOT, i.e. AC compressor
Then you uncompress it, which makes it cool down FAST
The faster it uncompresses the colder it gets
When system is low on "freon" it uncompresses too fast, not enough fluid to prevent it from uncompressing fast
If there is any moisture in the outside air then that moisture will start to freeze on the Evaporator and its tubes blocking air flow into the cab
Lower level of "freon" also causes system to run cooler in general
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