Massey 8570

[haefs]

Im having problems with the AC in my 8570 combine the pump is running it has freeon in it but neither line coming to the cab gets cold could the expansion valve be stuck shut or should I look at the temperature control

 

[used red MN]

This post is a few days old if you are actually using or need to use it you have probably went seeking help elsewhere. Do you have a set of A/C gauges? I suppose not or you would have probably given high and low pressure readings. Without the pressures we are guessing at best. An expansion valve is more likely to stick at a point it is to far open then to be stuck shut. It is the point where the high pressure liquid refrigerant is released into the lower pressure area beyond the expansion that gives the cooling. This takes place in the evaporator which is the coil in the cab the air blows through. Again not knowing the pressures we are all in the dark. Usually even cheapo methods of adding Freon give you a gauge. About the only way to take the farmer approach to repairing an A/C is to attempt to add Freon. When adding at a fast idle get a pressure of between 15 and 60 PSI on the low side where you add charge. Then raise the rpm to near full throttle and the pressure goes below or above this range and it is not cooling any at all you have a problem. I suppose the expansion valve is the most likely culprit. FYI, if you open an A/C system in the humidity of summer and you do not vacuum the system to evacuate the moisture you are asking for trouble.