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King Valves for Blow downs...Worth It?

Hello all, I'm planning to repipe my boiler in the spring.  I'm wondering if King valves are worth it for blow downs.

Does the cost of the king valves on the risers and the mains and isolation valves for the safety devices justify the cost and complexity?

It's a well maintained residential boiler and is skimmed and drained regularly and it's always pretty clean.  Will a true blowdown with king valves be worth it?

Comments

  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 15,455
    Probably not, but they are nice to have
  • JUGHNE
    JUGHNE Member Posts: 11,042
    edited January 2021
    Everyone of them I have come across will not operate, even after only 20 years.
    If operated every year probably would be OK.
    I imagine they need to be steam rated $$$.

    And no safety devices should have any isolation valves on them for obvious reasons.
    Return line valves would be handy for flushing.
  • ethicalpaul
    ethicalpaul Member Posts: 5,695
    I put them on my supply risers but that was only to be able to test one or the other riser. Totally unnecessary.

    On the main is OK if you want to build pressure in the boiler for whatever reason (like to test your controls, or for blowdown) but you also need one on the return otherwise the pressure will push the water out the back.

    Funny story, I didn't put one on my main yet, so if I close the 3 I do have, then the pressure goes from the return up the equalizer to the main and pushes all my boiler water immediately into the main. You learn not to do that pretty quickly LOL

    Brass or even SS ball valves aren't that expensive and I think they will stay operational for many years even without exercise.
    NJ Steam Homeowner. See my sight glass boiler videos: https://bit.ly/3sZW1el
  • mattmia2
    mattmia2 Member Posts: 9,575
    Maybe if you do it you should invest the extra bit in a flanged valve or some flanges or unions so you can take it out to free it up or replace it when it doesn't work.
  • Ron Jr._3
    Ron Jr._3 Member Posts: 603
    If the King valves are there just to test pressuretrol settings , I'd just invest in a 2nd pressuretrol . 
  • ethicalpaul
    ethicalpaul Member Posts: 5,695
    That can be one of their purposes. Is your thinking that having two pressuretrols means you never have to test them again? You must be a building superintendent :wink:
    NJ Steam Homeowner. See my sight glass boiler videos: https://bit.ly/3sZW1el
    Neild5
  • ChrisJ
    ChrisJ Member Posts: 15,592
    That can be one of their purposes. Is your thinking that having two pressuretrols means you never have to test them again? You must be a building superintendent :wink:
    He installs boilers in some of the most cramped closets I've ever seen.

    He deals with customers all day long.



    For me, I rarely use my king valves.  I find a wand does a far better job at washing things out once a year.
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • New England SteamWorks
    New England SteamWorks Member Posts: 1,505
    We find them incomparable when performing annual maintenance, and well worth the cost and expense.
    New England SteamWorks
    Service, Installation, & Restoration of Steam Heating Systems
    newenglandsteamworks.com
  • ChrisJ
    ChrisJ Member Posts: 15,592
    We find them incomparable when performing annual maintenance, and well worth the cost and expense.
    You feel a wand doesn't work as good?
    Single pipe quasi-vapor system. Typical operating pressure 0.14 - 0.43 oz. EcoSteam ES-20 Advanced Control for Residential Steam boilers. Rectorseal Steamaster water treatment
  • JUGHNE
    JUGHNE Member Posts: 11,042

    We find them incomparable when performing annual maintenance, and well worth the cost and expense.

    Key words annual and maintenance assure that they will continue to operate, unlike all that I have come across.

    Maybe they do the wand also.

  • GregWeiss
    GregWeiss Member Posts: 30
    They leak