morco boiler not firing up?

i had a similar problem. also changed the pressure switch on a boiler. then found it to that where the water enters the boiler through the filing loop was clogged with black residue inside the boiler not allowing it to reach pressure. look for a blockage is all i can say. look between the filing loop and where the water travels to the pressure sensor check for debris in between the route

kash
January 2013