I took my hot & cold pressure washer out of the garage. Has not been used in several years. Seems like the tubing in the chamber where the water is heated is clogged. The pump pushes water into the tubing but nothing comes out. Disconnect hose from pump to heating chamber and water comes out. I am thinking it's steel tubing not SS. So rust. Aside from trying to blow air backwards I do not have any great ideas. Now it's a cold pressure washer. Maybe there it a chemical I can pour in via funnel?