Steam Mains – How many do I need?

Oakvu

I live in a 110 year old home with a one-pipe steam system. I have 3 mains running from the boiler. The original main runs 10’x 25’x 15’x 25’ and feeds 6 radiators (4 1st floor & 2 2nd floor). The 2nd main runs 18’ and feeds 4 radiators (2 1st floor & 2 2nd floor). The 3rd main only runs about 5’ from the boiler before splitting to feed 2 radiators (1 1st floor & 1 – 2nd floor).

The original & 2nd mains have Main Vents at the end on T’s.

It usually takes about 25 minutes to have heat in all the radiators on a cold start. The Main Vents were replaced last year.

Can I increase the efficiency of the system by adding more Main Vents? Do I add them at the ends/turns on the original mains to get the steam to move faster thru the system?
It takes the original main the longest to heat.

The system is a good balance, but it seems I should be able to get the steam to the radiators faster.

Thanks.

Steamhead (in transit)

The original main

looks like it's 75 feet long. What is the pipe diameter in that main?

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Oakvu

The diameter of the original main is 3".

Steamhead (in transit)

That's a lot of air

you need three Gorton #2 vents on the end of that main. Nothing less will do. If no one in your area carries Gortons, you can get them online from State Supply or PEX Supply.

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Oakvu

Hoffman vs Gorton

On this original main, I have a Hoffman 75 Steam Main Vent and a Hoffman #4 Quick Vent. Should I replace the Hoffman vents with 3 Gorton #2's or should I just add 2 Gortons to what I already have? How does the Hoffman 75 compare to the Gorton #2? I just replaced these Hoffmans last year.

The 2nd main also has the Hoffman 75 & the Hoffman #4. This main is about 18' in length & 2.5" in diameter. Are these vents sufficient for this main?

Steamhead, I really appreciate your help.

Steamhead (in transit)

it would take 3.5 Hoffman #75 vents

to equal one Gorton #2. Install the Gortons and keep the Hoffmans for spares.

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Oakvu

Install of Vents

Do you install the 3 vents directly to the main with 3 separate drillings into the main or do you install them on a T(this is how the vents are now)?

If directly to the main, how far apart?

Jamie Hall

on a T

above the main -- and the leg of the T should join the main not at the end, but 10 or 15 inches or so back...