Installed New Wet Return, same old problem...

Jack_2

I recently installed a new wet return line (same size as old pipe) in a one-pipe steam system. This return line is attached to a longer main (appx. 40 ft. long) of a 2 header boiler (Weil-McClain). Just beyond where the wet return is attached to this main, a new larger main air vent was installed on a six inch nipple to hasten the steam to the furthest radiator in the house. This worked great for about 1 week. Then the old problem returned where this radiator always seems to get flooded (with resulting water hammer)intially when boiler is at start cycle. I don't think this is condensate since the amount of water escaping the air vent is fairly large. I also noticed that steam and sometimes fresh colored water is escaping from the new main vent after the boiler runs about a half hour. The water level in the gauge glass is appx. 1 inch from the bottom when the boiler is on. What are the possibilties here? If the boiler is generating wet steam (which is what I suspect) why would it work perfectly for 1 week after the new wet line was installed? Is it also possible that water from the wet return is backing up in to the main line thereby pushing it into the smaller branch to which the radiator is hooked up to? Thanx in advance for your responses.

Dale

My guess

I think the supply main isn't pitched all the way down from the boiler to the end. I think you are trapping water (Condensate) in the supply and it worked for awhile until the low spot filled up again. Make sure there is continous pitch between the supply high point at the boiler and the end of main vent.

Unknown

And the piping near the boiler

has to be up to the manufacturers reccommendation . Do you have the installation maunual , and does the piping match what it says ? Any way to post a picture of the piping ?

jweglarz@hotmail.com

make sure the 40' main is still insulated also level rad toward pipe to help get condensate out/and yes sounds like wet steam /squick may help and keep pressure low does sound like water is backing out of the boiler to get that much water in the system have a hartford loop or check valve?

Jack_2

Yes, I do have a spec Hartford Loop. No check valve though. And the main supply line seems to be pitched correctly. Does the boiler have to be skimmed after a wet line is installed? Someone told me that there might be oil and pipe threading material in the system and therefore the boiler has to cleaned again to get this stuff out. Does anyone know how to skimm a Weil-McClain boiler? I understand that chemicals cannot be used for this type. Thanx again for your responses.