Vertex Puratek RO system not working

[bkelly]

My Ro system is not producing any pressure its the 100 GPD unit the diaphram pump is running but makes a different sort of noise and does not create any pressure to the system. would that be a diaphram problem / anyone know where to get parts . or would it be anything else causing the problem. the prefilter pressure guage showns pressure so looks to be getting water from the house. and the pump is running so getting electricity. it just has a different sound to it and nothing coming out.
thanks