No Venting on a 2 pipe set up.

mpitt

Good morning everyone I just had a quick question. I've been looking over my steam setup for the past few months since moving into a house in a few things seem to be of interest. I mentioned in the past that my system went set to two PSI plus or minus short cycles continuously on pressure cut in cut out. Perhaps the boiler is a bit oversized after home retrofits but I've noticed that there's no venting on the main lines supplying the convector fin radiators. I'm wondering if this could be contributing to the system pressuring up to easily. The main stack is also 2-in copper that splits to one and a half inch copper feeding either side of the house. Feeds to the radiators look to be about half inch copper but I know all the copper is the heavier duty gauge stuff. I know this isn't ideal but it's what I have. Is the system pressuring up too quickly because it's trying to push the air out one might think? Perhaps this was a previous vent location that has been terminate? 

clammy

You may be better trying to get a pro there to evaluate your system . Copper is not the material of choice for steam systems . Possible aside from main venting it may be time to up date and replace radiator vents if they happen to look ancient and are not venting properly .
It would seem repairs were done due to leaks hence the copper piping was the preferred replacement material . If this is your first home w steam then you should do some research and educate yourself there’s plenty of helpful info on this site which should help you make sure you get the right person in to look at and evaluate your system .
When was the last time the boiler was service ,meaning flushed ,sight glass assembly removed and cleaned ,low water cut off check for proper operation , flushed if mech and if probe type removed and cleaned .
As a quick note if there are not main vents then oviolously whoever did the repairs should be the last person to call . This is a single pipe system correct I ask because the I see a trap at the end of the steam main in a one pipe system it has no place being there which to me means wrong contractor at some point . Peace and good luck clammy

mpitt

Hi for all that it does look like a two pipe system to me no vents on the RADS one pipe in one pipe out there is a separate return line that runs to a condensate tank. I believe the steam trap at the end of the main run it to keep steam in the main line but then allow any additional main line condensate return back to the return line. See the additional picture to see the line off the main into the rad and then separate return line above it. All the rads are fed this way. I also see an area that was terminated at the end of the other side of the main. Potentially where a valve could have been. I could map out the runs and traps it that might help. I blow down the boiler once a week and check the LW cut off at the same time. I've also serviced the burner and changed out the oil/fuel line filter. I've cleaned out the pigtail and sightglass. It's and old boiler but mechanically working well from what I can see. 

Jamie Hall

That one lonesome trap in your photo is functioning as a crossover trap, although it is not piped correctly (no surprise there -- whoever did the repipiing really was kind of clueless). The lower horizontal pipe in that photo is a dry return, and when it gets back to the boiler there should be a nice big vent on it. If there is a similar horizontal main arrangement somewhere else that should have a similar arrangement.

clammy

Well the trap makes sense if you have a condensate pump which is kinda ironic being most residential single and 2 pipe system work usually without a condensate pump unless things have been knuckle headed . Personally I would all in my powers to rid ur self of the condensate pump being it will be expensive to replace and there’s really no need for it as from what I see if piped and set correctly condensate should return to the boiler by gravity .
Being you have a condensate pump I don’t think you will have any main vents being it all vents through the trap and then through the vent over fill on the tank . From the looks of the mains there zero insulation which really doesn’t help get heat to the radiators but it does a nice job of keeping the basement warm .
Peace and good luck clammy
Where u located ?

mpitt

Ok yes, crossover trap separating steam in the main and any leftover condensate to drip down once the crossover valve opens up and returns gravity fed into the dry return line. Also yes now I do see what would be considered a large over to the atmosphere "valve" or air escape one might call it. 

This is the other end of the main line. Similar crossover situation just a different trap. 

If in the future I was replacing the aging boiler perhaps I could loose the condensate tank but would need to add venting I guess.. thanks alot. 

Mike

mpitt

mpitt

I'm on the east coast of Canada. I'm not sure who's done the work so far but out of the couple companies I've talked to when they hear Steam they don't seem enthused