I have a 1 pipe steam system. There was no main air vent installed, I think it was plugged. Last year, I have a plumber installed a Gorton 1 main air vent where it was plugged as seen here: Here is the main pipe: This is the end of the main pipe and then curve to the left to a raditor and then pic 1. There are 3 risers that feed 2 raditors in the first floor and 4 in the second floor. My question is, by having the main air vent there at the return, does it serve any purpose? I haven't really noticed. Also, will adding another Gorton 1 with a tee there will help? I have a water hammer problem in my master bedroom. I hear the loud bang once the thermostat reaches the set temp or boiler stop firing. Air vent is changed, radiator is pitched, valve is fully open. Also, my bathroom vent and third bedroom hisses loudly. A few days ago, I put in Squick to clean the boiler. I haven't drain it out yet. The water glass gauge is filled half way. Water only move at most 3/4" when the boiler is on. Any ideas what else to check for?

A local contractor was highly recommended and I think I finally hit pay dirt. He measured the rooms and windows and asked about insulation etc. He was raised around boilers etc, his dad worked for burnham so he's not just a sales guy like everyone else i had over was. he also does installs for the triangle tube bigwigs for protoypes and he is very passionate about his work Sorry for such a basic question but is this being cast iron different from other low mass boilers? I have this idea in my head new things are mostly steel? And what is wet base(good/bad/indifferent)? I didnt notice that on the pamphlet until after he left. this guy has this Solaia in his own house with a triangle tube tank and the top of the line tekmar (you guys probably know which one.) just off the top of his head he thinks i'd get the SL4100 but has to crunch the heat loss of course. [url]http://www.boyertownfurnace.com/images/PDF/Solaia.pdf[/url] [url]http://www.boyertownfurnace.com/pages/products-solaia-boilers.htm[/url] I found this flyer on the website but he didnt give me this one... if i'm reading it right, he would use a riello F5 (but i'm not sure) [url]http://www.boyertownfurnace.com/images/PDF/Solaia%20Flyer.pdf[/url] He also recommended the tekmar 260 vs the 256 and said it would save me a lot of money. Ballparked 10% on that plus 10-15% with new boiler and the reillo. He said he only installs riello anymore. He stated he would get rid of my expansion tank on the ceiling and put some sort of bladder control(?) in. He talked in detail about my insulation issues and I informed him i want to seal up the house more. He said he'd keep my existing circulator since it's newer and add 2 more. He feels the lack of heat in my spare bedroom is an infiltration issue since I have over 30 ft of baseboard in there. I feel very good about this guy, he offered to let me come to his house and see / hear this boiler in action. He was also straight up with me and told me due to my layout, i couldnt do a direct vent. The other guys all led me to believe i could. But he did say i could do the fresh air intake if need be (will price it with and without. He mentioned something about primary and secondary but i forget what in relation to. I think we were talking about bypass and he mentioned something about feeding 10% of the hot water back in..i honestly forget..sorry. He said the chimney could be an issue down the road but estimated i only have about 15 ft to reline and he knows someone if I need it down the road. So what are your opinions of this 'eurpoean' setup ? Thank you