have a 2010 F150 4x4 and the a/c blow cold until yesterday. As I was walking by it something blow out from under my truck and I seen it was freon .Do theses trucks have blow off valve to relief the a/c pressure valve its to high and why would it do this and were is in locate ? NOw my a/c is blowing hot air

 

probably blew a line. If it came from under the truck I would like maybe something on the compressor.

 

I agree. Start looking for cracks, leaks, etc.

 

I would put a couple of cans of 134a with dye in it, then look for the leak.

 

Look for obvious leaks, blown lines, etc first.

 

I don't think it is a blown line because .the compressor still kicks in and out and with the gauges .I have 25psi on the low side and every once in a while.After you drive is it will blow some more out.

 

Well that info would have been nice in your OP. Anything else you would like to add?

 

Is the a blow off valve on them? and no that is all the info

 

Yes they have a relief valve on the compressor. Yours maybe malfunctioning. Or you have a blockage on the high side creating enough pressure to overcome the relief setting

 

rymax101 do you know were I can find that valve
or should I take it to a dealer?