Results 1 to 12 of 12
  1. #1
    Jeff Beck's Avatar
    Jeff Beck Guest

    Default Strange gas shut-off valve

    New furance in a 54 year old house.

    The natural gas shut off valve is something that I've never seen before.

    I used my combustible gas sniffer and soapy water and found no leaks but the valve looks strange.

    Has anyone ever seen one like this? Is there any need to replace it?

    Jeff Beck
    Foresight Home Inspection LLC

    Similar Threads:
    ***IMPORTANT*** You Need To Register To View Images ***IMPORTANT*** You Need To Register To View Images
    OREP Home Inspector E&O Insurance

  2. #2
    Jon Randolph's Avatar
    Jon Randolph Guest

    Default Re: Strange gas shut-off valve

    I have never seen one like that. Those smaller valves probably went to an old pilot or something. I would probably recommend improvement (replacement with a modern valve). At a minumium, those fittings coming off of the valve need to be capped.


  3. #3
    Join Date
    Feb 2008
    Location
    Chicago IL
    Posts
    1,939

    Default Re: Strange gas shut-off valve

    It's not a new valve, it's ancient. We used to use those on boilers years ago. The main valve was piped to the gas valve/burner assembly. The little valves were piped with tubing for the standing pilot(s).
    You had to light the pilots with the little pilot tube while the large valve was in the off position, otherwise ... boom. I'm very surprised it doesn't leak, those valves are notorious leakers.
    I would recommend replacement with a new standard gas cock. The pilot valves are perfect for some kid to wonder 'gee what's this'.

    www.aic-chicago.com
    773/844-4AIC
    "The Code is not a ceiling to reach but a floor to work up from"

  4. #4
    Richard Rushing's Avatar
    Richard Rushing Guest

    Default Re: Strange gas shut-off valve

    That is an old DIY type install.

    BTW-- that threaded end (open) at the pilot valve needs to be capped off.

    RR


  5. #5
    Join Date
    Mar 2007
    Location
    South-West Michigan
    Posts
    469

    Post Re: Strange gas shut-off valve

    That valve is o-l-d. I have seen a few, some did leak.

    Randall Aldering GHI BAOM MSM
    Housesmithe Inspection
    www.housesmithe.com

  6. #6
    Phillip Bates's Avatar
    Phillip Bates Guest

    Default Re: Strange gas shut-off valve

    That valve, though rarely seen any more ,was called an A-B Valve & incorporated 2 valves & that was main valve gas(A) & pilot valve gas(B).As they were a lubricated valve of the spring-loaded type they often over time would leak.It was usually found on boilers & furnaces where the main appliance valve(eg these days a 24 volt valve inside the casing of the furnece/boiler usually without a standing pilot) did not have a connection for the pilot gas so this valve meant you had direct gas to a pilot which usually incorporated a thermopile & did not have 100% pilot gas shut-off in the event the pilot went out.No longer allowed we replace them or order the replacement of them when found.


  7. #7
    Join Date
    Mar 2007
    Location
    Ormond Beach, Florida
    Posts
    25,307

    Default Re: Strange gas shut-off valve

    Quote Originally Posted by Richard Rushing View Post
    BTW-- that threaded end (open) at the pilot valve needs to be capped off.
    Capping them off IS REQUIRED.

    So recommend the gas company leak check the valves and cap off or remove as necessary.

    Jerry Peck, Construction / Litigation Consultant
    Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )
    www.AskCodeMan.com

  8. #8
    Join Date
    Mar 2007
    Location
    Near Philly, Pa.
    Posts
    1,632

    Cool Re:old style gas shut-off valve

    Markus, Phillip, et al are correct. One of the other problems with this valve is there large shutoff does not affect the pilot---only the smaller shutoffs do. That means you can shutoff the main burner and gas can still flow to the pilot whether there is an open flame or not.

    This valve is exactly why safety pilots with a flame proving device (thermocouple) were invented.

    If you try to replace just the shutoff with a modern ANSI Z21.15 shutoff, you have to provide for ignition. That would mean installing an aftermarket field installed unlisted pilot retro kit. The Fire Code does not want you performing such modifications unless you have a kit approved by the mfr. for that model appliance. Since you see these on dinosaurs, it would be better to replace the entire appliance with a modern higher efficiency model. Heck, if you get a 95% furnace, you may qualify for the Tax Credit up to 30% or $1,500. Most of those old monsters are rotted out and grossly inefficient anyway.
    Bob

    Keep the fire in the fireplace.

  9. #9
    Join Date
    Mar 2007
    Location
    Ormond Beach, Florida
    Posts
    25,307

    Default Re: old style gas shut-off valve

    Quote Originally Posted by Bob Harper View Post
    If you try to replace just the shutoff with a modern ANSI Z21.15 shutoff, you have to provide for ignition.
    Bob,

    Those are no longer being used for standing pilots.

    Therefore, wouldn't replacing the valve with a modern valve be acceptable?

    Jerry Peck, Construction / Litigation Consultant
    Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )
    www.AskCodeMan.com

  10. #10
    Join Date
    Mar 2007
    Location
    Near Philly, Pa.
    Posts
    1,632

    Cool Re: Strange gas shut-off valve

    Technically, the AHJ should rule on this. There are plenty of aftermarket conversion kits and separate components that would 'work'. The question is more one of responsibility.

    It is a problem for me when I get called to reline a collapsed flue serving one of these appliances. I have Red Tagged the appliance before when it had so many gas leaks, it was hard to separate them and the pilot and burner were making high levels of CO that the unit was leaking into the CAZ. That's why you usually have several factors against refurbishing the clunker in favor of replacement.

    For those not following, you 'could' replace this mess with a listed ball valve to a 100% combination valve. This means the appliance valve does double duty: flame proving and burner operation. Flame proving may be by a heat generated signal (thermocouple w/ std. pilot) or a Direct Spark Ignition (DSI), Hot Surface Igniter (HSI) or Intermittent Pilot Ignition (IPI), which use flame rectification for flame proving. Also, a combination valve has a regulator that balanced house inlet pressure to a preset level for the manifold pressure to the burners. Old unregulated burners could see their flames fluctuate up and down with changes in house pressure as other gas appliances opened or closed. Such a valve can be controlled by a thermostat. There are some really old valves that used a simple solenoid connected to a Tstat.

    Bob

    Keep the fire in the fireplace.

  11. #11
    Join Date
    Mar 2007
    Location
    Ormond Beach, Florida
    Posts
    25,307

    Default Re: Strange gas shut-off valve

    Bob,

    You are not following what I am saying and asking and what is shown in that photo ... that valve ONLY SERVES AS a shut off valve for the gas line ... THERE ARE NO pilot lines from that valve ... the furnace has already been replaced and those are no longer needed and no longer being used.

    That valve IS ONLY serving as a on/off valve now.

    With that status, is there is reason that valve cannot be changed out to a regular modern valve?

    Jerry Peck, Construction / Litigation Consultant
    Construction Litigation Consultants, LLC ( www.ConstructionLitigationConsultants.com )
    www.AskCodeMan.com

  12. #12
    Join Date
    Mar 2007
    Location
    Near Philly, Pa.
    Posts
    1,632

    Smile Re: Strange gas shut-off valve

    I missed the part about a new furnace with this old valve. Yes, just replace it with a new Z21.15 ball valve--done.

    Boy, that was a lot easier.

    Keep the fire in the fireplace.

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •