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Another low pressure gauge problem

Finally had my Wika #9851720 low pressure gauge installed, along with the pressurtrol as the back up control.

So, the needle was about 1/4" below 0 when first installed, but when we cycled the system it appeared to get sucked into vacuum, and it's been there for the last 1/2 hour. We could not get it to 0 with the calibration screw. It's just jiggling (see photo) down in no-man's land.



  • MotownSteamer
    MotownSteamer Member Posts: 110

    So I just shut the system down and the needle seems to have jumped into a pressure reading. Looky here
  • ChrisJ
    ChrisJ Member Posts: 14,946
    edited February 2012

    Remove the gauge and see if you can get all of the water out of it.

    My guess is it got a lot of water in the capsule as well as in the end of the connector and its causing it to have problems.

    My 3.0PSI Wika gauge didn't like water either so I raised it up a few inches and its much happier.  It looks like yours is right where water can collect.

    I would also cal the gauge for zero with it removed from the system and dried out.  That is true zero without any slight vacuum or pressure effecting it.  Try blowing into the gauge before you reinstall it to make sure it works right.  You should be able to move that gauge easily with your mouth.   If you can't it may be damaged.
    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
  • MotownSteamer
    MotownSteamer Member Posts: 110
    another update

    So, I opened the port on the rear of the boiler and purged all the air/steam. The original pounds gauge returned to 0 from a vacuum, but the lp gauge jumped to 20. I closed the port back up, and the needle starts to head towards 0
  • sensitive gauge problems

    all the devices on that manifold should be well up above the horizontal pipe by a few inches, and all at the same height. the pressuretrol now has a longer/higher nipple which may hold a column of water which can show up as pressure on the gauge. any gauge should be off the boiler when zeroing the needle.--nbc
  • MotownSteamer
    MotownSteamer Member Posts: 110
    Are these controllers even hooked up right?

    Thank all for the replies.

    My original intention for today's install was to have the Pressurtrol (which came with the new boiler) as a back up, and for the Vaporstat as "primary". They were wired together in series. Is this correct? The installer also changed my P-trol settings; he now has it cutting in at 2 pounds and out at 3!
  • Jamie Hall
    Jamie Hall Member Posts: 21,524
    Wired in series

    is correct.  That way either one would cut out the system when the pressure got above its cutout point.  The vapourstat should be set much less than the 3 pound cutout on the pressuretrol, so it will control the system.  The pressuretrol is just a backup.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • Abracadabra
    Abracadabra Member Posts: 1,948
    pitches to the left

    looks like that horizontal gauge/pressuretrol header pitches to the left and will collect water which is most likely causing the problems you are seeing.
  • MotownSteamer
    MotownSteamer Member Posts: 110
    this is what I was trying to accomplish

    Thank you for the replies. We'll pull this apart and re-do it. I was going for this sort of set up:

  • FJL
    FJL Member Posts: 354
    Gauge Needle on Zero

    So does the gauge need have to be sitting at zero to give me an accurate reading when the boiler operates and creates pressure? Mine has dipped below zero during vacuum and it sits below zero when inactive.
  • ChrisJ
    ChrisJ Member Posts: 14,946

    FJL, do you have pictures of how your gauge is installed?

    Mine use to behave the way yours is before I raised it up to keep water out of it.
    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
  • FJL
    FJL Member Posts: 354
    My Set Up

    Check out this thread for pictures of what I have now:   http://www.heatinghelp.com/forum-thread/140226/New-V-stat-Header

    First picture in the thread is of the original installation.  Scroll down and you will see the new set up.  Ironically, in the picture, the needle is at zero, but I think last time I checked it was not.  But I am not sure.

    For two years, I had that gauge attached to a radiator, sitting on to of the brass pigtail you see in the picture and the system went into vacuum when the boiler turned off and the needle would go past zero and then settle back either at zero or pretty much near zero is not exactly at zero.
  • MotownSteamer
    MotownSteamer Member Posts: 110
    the gauge is gone

    I pulled the gauge today. The needle jumped to 20 and wouldn't budge. The adjustment screw was useless. I tossed it and ordered the Wika 0-3 psi and am rebuilding the manifold. I have crosses with plugs for access and cleaning of the horizontals and pigtails. Everything is going UP. Anything else that hasn't been suggested? BTW it's all black pipe, not brass.
  • Maine Vent
    Maine Vent Member Posts: 130
    Bad luck with my WIKA also

    I have had a crazy time with my 0-10oz WIKA gauge. I am looking into these Dwyer gauges. I'll post a page with some low pressure and also a combo gauge that will read vacuum along with low pressure. Only the scale is different it will read in w.c., & kPa this is not a big deal, you can get a conversion program off the web that will convert w.c./kPa to oz. or to pounds. I'm wondering if the vacuum the boiler was making might have damaged the internals of mine???
    Weil McLean SGO4, Riello Gas Burner
    404 sq ft EDR
    Old Burnham V8 Removal
  • MotownSteamer
    MotownSteamer Member Posts: 110
    Please check my work

    Ok, I just finished the rebuild. I'm worried about the shiny black pigtails I got; the are not the dull cast iron like the original. Are they ok? Did I design this correctly or are there flaws? I do not have my new lp gauge yet; hence the temporary (galv) cap on the gauge riser to the right. I'll also put the psi gauge (left) on a riser after a trip to the hardware store tomorrow.
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