On board Air Compressor Freezing?

[CBari]

I am not sure exactly what is going on but looking for some experience and guidance. My factory pac-break compressor that was mounted in the engine bay spit the bit after about 3 years back this summer. The reed valves appeared to have rusted in two so I replaced the compressor with a larger duty viair 400c compressor which I mounted to the frame rails underneath the drivers rear seat and added a 5 gal tank underneath the truck between the transfer-case and the fuel tank. I left the pressure switch and the pacbrake solenoid valve on the old compressor and just disconnected the power. Thought was that this would keep those valves warm and I wouldn't have any freezing issues. What happens is that if the truck sits out in the cold or driving in the cold and the pressure drops enough from use to trigger the compressor it kicks on as it should but sounds louder and runs for ever like it isn't building and pressure. I can flip switch to the power on the compressor and shut it off and after the truck sits inside at night or it warms above freezing outside I can turn it back on and all is fine. So obviously something is freezing up but what and how do I prevent it. I have in the intake for the compressor run up between the outside sheet metal and the inside of the bed. I thought this would be a dry spot but I guess it could be getting some moisture from the spray of the tires. I also have a drain on the 5 gal tank and very little moisture comes out of it when I drain it.

 

[mpaulson]

I'm having issues as well with the cold. I just installed my 5 gallon tank and ping tanks this past weekend and my compressor is mounted in the truck box as well as the full Pac brake valve set up with the compressor vent off valve and the bag control solenoids. Yesterday when I fired up the compressor it pressured up to the 150 psi like it is supposed to and then cut out and the relief valve did it's venting but stuck open a bit and the tank pressure dropped to 70 psi before the valve closed off!!!!@### Then the compressor had to do it all over again. Then latter while playing around with the bag pressures, the inflate valve was stuck in the open position a little and the bags were slowly inflating while the switch was off. I had to play with the switch a bit to get it to seal up and stop creeping. My compressor and valves are mounted in the box on the wall in front of the wheel well and I have a canopy on the truck, so they are not getting any moisture. I wonder if a guy should get a little bit of air tool oil in the line to lube the valves a little to help them from having ice bonding to the parts? It was ONLY -38 degrees yesterday.

 

[JJPage]

Moisture/humidity is present in the air you are compressing, just think where the supply air is coming from...that moisture will freeze and cause valves and diaphrams to stick or not seal. I used to dump alcohol(products are available that will not harm sys) into the gladhands regularly in the winter months, it would travel through the system and prevent freezing issues. You need to provide yourself an access port to do the same.

 

[mpaulson]

I just called Pac brake and asked but the tech guy isn't in till tomorrow. The sales guy hadn't heard of this happening before. So I'll call them tomorrow and see what they say about this issue as well as suggestions for adding oil or alcohol to help this issue.

 

[JJPage]

I just called Pac brake and asked but the tech guy isn't in till tomorrow. The sales guy hadn't heard of this happening before. So I'll call them tomorrow and see what they say about this issue as well as suggestions for adding oil or alcohol to help this issue.

You may want to PM Jelag on this forum, he distributed them(pacbrake) for years.

 

[Gonzo 1066]

I had some issues with the cylinder on my exhaust brake freezing shut. Got some semi brake line antifreeze (alcohol) and put about a quart in my 3 gallon air tank. Problem solved.

 

[mpaulson]

I had some issues with the cylinder on my exhaust brake freezing shut. Got some semi brake line antifreeze (alcohol) and put about a quart in my 3 gallon air tank. Problem solved.

The antifreeze wouldn't get into the valves in my case since the air compressor only has about a 8" copper line that goes straight into the valve block, so the valves would never get a dose of it. It obviously works in your case for items that are down stream from the tank, but wouldn't the liquid just sit at the bottom of the tank and not get into the lines going out of the tank? Just my logical thinking here. Or does it mist or vaporize in the tank so that it gets into the lines?