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Other parts of the world with district heating don't leak steam. Is it just because they use (liquid) water and not steam? The water is still plenty hot enough

Other parts of the world with district heating don't leak steam. Is it just because they use (liquid) water and not steam? The water is still plenty hot enough for steam to form in leaks, so there's perhaps some factor that makes leaks more tolerable in steam systems? Different corrosion concerns perhaps, air leaking in is less corrosive?

wongarsu 4y ago
Our smallish city has district heating with hot water, and no steam rising from the streets.
tedunangst 4y ago
I think it's an American thing. Our pipes are just that much freer. New York and Philadelphia systems leak steam, too.
mangecoeur 4y ago
Steam based systems are just obsolete, steam under pressure leaks easily unless you do plenty of maintenance. Most district heating systems use liquid water in a closed loop. In fact most operators today are looking to further reduce temperatures to reduce losses and improve efficiency. You only let this much steam escape if you really dont care about saving energy/money
- bobthepanda 4y ago
  The issue is generally for these large historic systems, the capital cost of replacement is larger than the savings. Because the streets of New York had many utilities laid out very early, there’s poor mapping and everything underground is haphazard, and disrupting somebody else’s utility system will get them to sue you.
  - mangecoeur 4y ago
    Well it's more a infrastructure policy issue than a technical one. Steam systems are so wasteful its hard to lose money upgrading them. As you say though, if you have different utilities under different ownership, some state owned and some not, it's more a problem of managing the upgrade as part of a long term infrastructure program if its not coordinated through a central utility provider.
    - bobthepanda 4y ago
      That, and that even if there was a central utility, documentation was not a priority at the turn of the 20th century, and so the locations of infrastructure are either not even mapped or incorrect.

wongarsu 4y ago

Our smallish city has district heating with hot water, and no steam rising from the streets.

tedunangst 4y ago

I think it's an American thing. Our pipes are just that much freer. New York and Philadelphia systems leak steam, too.

mangecoeur 4y ago

Steam based systems are just obsolete, steam under pressure leaks easily unless you do plenty of maintenance. Most district heating systems use liquid water in a closed loop. In fact most operators today are looking to further reduce temperatures to reduce losses and improve efficiency. You only let this much steam escape if you really dont care about saving energy/money

bobthepanda 4y ago
The issue is generally for these large historic systems, the capital cost of replacement is larger than the savings. Because the streets of New York had many utilities laid out very early, there’s poor mapping and everything underground is haphazard, and disrupting somebody else’s utility system will get them to sue you.
- mangecoeur 4y ago
  Well it's more a infrastructure policy issue than a technical one. Steam systems are so wasteful its hard to lose money upgrading them. As you say though, if you have different utilities under different ownership, some state owned and some not, it's more a problem of managing the upgrade as part of a long term infrastructure program if its not coordinated through a central utility provider.
  - bobthepanda 4y ago
    That, and that even if there was a central utility, documentation was not a priority at the turn of the 20th century, and so the locations of infrastructure are either not even mapped or incorrect.