Single Pipe Steam Main Pitching

Pete_18

I'm just a homeowner as well that just spent multiple months working through my neglected 1903 1-pipe steam system, but I'd personally leave your mains alone. The dead men that ran those pipes generally knew what they were doing.

Are your mains vented? If so, with what kind? You should see the vent right before it drops down towards the floor at the end.

Are your mains insulated?

Have you checked your pressuretrol to ensure that it says .5 on the front and 1 on the differential when you open it up?

What types of problems are you having? Unequal heat? No heat on certain radiators? Radiator hissing? High fuel bills?

[Deleted User]

Single Pipe Steam Main Pitching

I bought an old house (90 years) with a single pipe steam system. I am trying to understand this system and get the heat working efficiently.

I have two main steam pipes in the basement, which are connected at their ends by a loop that runs along the floor to the main boiler.

I read on this site that the steam pipes should be slanted 1 inch for every 10 feet. I don't know if that means the pipes of the risers or the main.

Both mains slightly slope away from the furnace, not towards it. It appears to me that the condensate is draining down the loop rather than back down the main to the furnace. There is no water hammering of any sort

My question: Should I be concerned? And should I be concerned enough to call a professional to slope the main pipes towards the furnace? Would the heating system operate better?

Regards,
Mike
Long Island

[Deleted User]

Hi Pete,

This heating system has been an adventure in learning. The former owner had the old insulation removed from the pipes, so I reinsulated. Then, I replaced the main vent air valves. What a huge difference. One was jammed shut.

I did all that you suggested as well.

It seems that the previous owner recently had the copper pipe loops at the end of the mains added or replaced. I know they are new by the copper used and how they are secured to walls.

The house doesn't appear to have settled at all..no cracks in the plaster or other signs of settling. Though the steel straps hold the main pipes to the floor beams could have stretched changing the pitch.

I visited the local plumbing supply and an old timer said make sure your pipes haven't sloped the opposite way as a result of the house settling. So I checked, hence my question.

It appears to me that the condensate is draining down the loop rather than back down the steam main to the furnace. There is no water hammering.

My concern is whether or not it is draining in the correct direction and if the loop will eventually clog with debris over time.

Also, the one main, which is the longest and more steeply sloped away from the furnace, takes a lot more time for the steam to make it through compared to the other main.

I am trying to find out if I had the pipes pitched towards the furnace, would it facilitate steam moving through the pipe quicker and would I be preventing a future problem.

Hope you are having good luck with your new (old) home.

Regards,
Mike

John S.

Mike,

It sounds like you have a perfectly normal one pipe parallel flow system. This system is considered superior in design to that of a counterflow system.

The longest main will heat up slower than the short assuming you have the same capacity vent on each main. There's simply more volume of air to exhaust.

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

Pete_18

pipe pitch

It has been quite an experience, but with everyone's help I think I'm finally getting to the point where my steam system is working properly. It doesn't whine all night long with banging and hissing anymore, it actually heats up the whole house, etc. It amazes me that the former owners left the house at 55 degrees for 25-30 years and suffered, but without this group, I'd probably still be suffering too.

My one complaint still is that I'm wasting a lot of fuel, but I'm not sure I can fix that without more insulation in the house and a better boiler (mine is a gigantic beast from 1979-1980).

I think the main point of having the right pitch on the mains is that if it's not pitched right, the condensation could flow the wrong way and as a result, will stop the steam in its tracks. Someone who knows more than I do will need to chime in specifically on that. I would think you'd be hearing some type of water hammer though if it was really bad.

What type of vent(s) did you put on your long main? How long are your mains and what size are the pipes? If you provide this information, one of the experts will probably chime in and let you know what vents/how many you really need. One thing worth trying as a test is taking the vent off the long main and seeing if it heats up any faster. If it heats up significantly faster, this is a sign that a better vent / more vents could help.

My long main definitely takes a little longer to heat up, but I find that with good vents on the radiators that I can adjust based on size and location, the house is actually heating fairly balanced now.

Did they use copper on your mains or once it drops down to the return? Everything I've read from the experts on the board says that copper is terrible on the mains, but I too ended up with a piece of copper on my returns because they obviously didn't want to pay for it to be done right or couldn't find a plumber that knew what to do.

P.S. If you have 1-pipe steam, that thing that boils water and makes steam is a boiler. I too used to think that everything that made heat was a furnace.

Steamhead (in transit)

Mike, it sounds like

the longer main needs more venting. Measure the length and diameter of each main and tell us what vents are on them. We can tell you what you need.

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"