Main Pitch

Annie

I brought in a professional plumber to take a look at adding main vents to my system after discovering I didn't have any.  The guy said that my main is pitched wrong and cannot guarantee that if he were to put in main vents that they would help any.  I am very confused. 

My system doesn't bang at all.  The main is pitched towards the boiler rather than pitched towards the return line (which he says it supposed to be). 

Can someone point me in the right direction?

crash2009

I think we are going to need some pictures

 for this one. On one hand your plumber is correct. On the other hand there is a possibility that you have a counter-flow main.

Annie

Pictures of Main Vent

Hope this gives you a good picture.

Jamie Hall

Either way

Annie, either way is correct for the pitch of mains in a one pipe steam system.  If they pitch away from the boiler, and the condensate is dropped in a pipe at the end and returns to the boiler through a wet return, that is called a parallel flow main.  If they pitch towards, the boiler, they are called counter flow mains, and the condensate just drops to the boiler at the boiler.



In either case, the correct location for the main vents is at the far ends of the mains -- preferably not right at the end, but a little ways -- a few inches -- towards the boiler from the ends.  They should also be mounted on about 6 inch nipples going straight up.