Right. So the first compressor didn't work but machinemart kindly exchanged it. So instead of an ex display one I got a boxed one... result. But I left one of my fittings on the old one.... Gotta pick that up from machinemart tomorrow to test the system but it's in its place. The abac has adjustable differential pressure where as the new littler one doesn't so it's gonna be interesting trying to get them synched...