my brand new used service truck has a boss series 35 hydraulic compressor on it. When I turn on the compressor the idle will speed up and it will build 150 psi but never sounds like it shuts off and truck doesn’t idle down unless I shut off the compressor. Contacted boss and he said There was nothing wrong as it is a rotary screw compressor and that’s what they do. Previously I had vanguard compressors which only idled the truck up when it was building air and then returned to low idle. Anybody have any insight on this? I really hate to have the truck idled way up the whole time the compressor is on and it’s a pain to turn it on and off every time I need air.
Looks like that's the way that it's designed. You should be able to install a switch on the chassis somewhere to get around that. My autocrane screw compressor is the same. From here https://www.google.com/url?sa=t&sou...Vaw0-vaqEWfHbZTGMvjgg9BMG&cshid=1558061194497
All the rotary compressors I've been around were stationary types, and they run all the time. They just have a valve like a large unloader valve when no air is needed in the tanks. Rotary moves a lot of air, but you have to live with it running all the time.
How about a pressure switch in either the compressor on/off switch (might cause more PTO clutch wear than usual) or in the engine high idle wire (if it exists and not being done by CANBUS or something) (if the compressor can handle being run at low RPM when idle)
The compressor running all the time wouldn’t bother me if I could add a pressure switch or something so the truck didn’t run idled up and burning unnecessary fuel. I’ve always had maintainer beds which had the compressor on/off switch inside the front compartment with all the light switches. This one has the compressor switch on my crane controller which is handy because I can keep it next to me and not make a bunch of trips to shut it off. It also has a high/low idle switch but it only works on the crane part and won’t idle the truck down when the compressor is on.