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How to test Conbraco size 1 relief valve?

Any ideas how to test this relief valve?

I pushed and pulled up and down on the stem part and it doesn't move much either way.



Thanks.

Comments

  • mattmia2
    mattmia2 Member Posts: 9,572
    replace it.

    It looks like there was some sort of a lever that pushed on something inside that stem but in addition to being 70 years old and having a high likelihood of failure based on age alone, it also likely doesn't meet modern relief valve standards.
    ilikebeansHap_Hazzard
  • ilikebeans
    ilikebeans Member Posts: 18
    mattmia2 said:
    replace it. It looks like there was some sort of a lever that pushed on something inside that stem but in addition to being 70 years old and having a high likelihood of failure based on age alone, it also likely doesn't meet modern relief valve standards.

    Is this as simple as replacing a vent on a radiator? Just screw the old one out and new one in? 

    What could it be replaced with?

    Thanks.
  • EdTheHeaterMan
    EdTheHeaterMan Member Posts: 7,713
    edited September 2022

    There is a handle missing. The handle is not just a small flat metal blank with a hole in it like the lever on an auto feed valve (Pressure reducing valve). This is handle has a detailed lever shape that fits in the slot of the vertical valve stem. The other end of the handle will rest on the side of the relief valve. When you pull up on the missing handle the lever action will have a mechanical advantage that will lift the stem. Since this has obviously not been operated or tested in many years, if you are able to open the valve to test the operation, The valve most likely will not seat properly and you will need to replace it anyway.


    Good luck
    Edward F Young. Retired HVAC ContractorSpecialized in Residential Oil Burner and Hydronics
    ilikebeans
  • Hap_Hazzard
    Hap_Hazzard Member Posts: 2,846
    I thought you were supposed to replace these every few years as a matter of course. I can’t remember where I read that, but I replaced mine last year because, as far as I know, it was as old as the boiler. 

    Conbraco is now owned by Apollo Valve. I looked up the application in the Apollo catalog and ordered an Apollo Valve 13-510. It’s supposed to open at 15 PSI, though I don’t know how you’d test that. The only test I know of is to pull the lever and see if steam comes out. 
    Just another DIYer | King of Prussia, PA
    1983(?) Peerless G-561-W-S | 3" drop header, CG400-1090, VXT-24
    ilikebeans
  • mattmia2
    mattmia2 Member Posts: 9,572
    It just unscrews and you screw a new one on. Pay attention to pipe size and gender. Use teflon tape or dope or both. Relief valves are available with male and female threads. You might need a nipple or a coupler. The discharge should be piped to the floor with pipe rated for the temp of the fluid in system with the open end unthreaded. The pressure has to be at or below the rating of the boiler and the discharge capacity has to be greater than the input of the boiler.
    ilikebeans
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 15,452
    The way to test it is to take it off the boiler and hook it to an air compressor. But that valve needs replacing
    ilikebeans
  • hot_rod
    hot_rod Member Posts: 22,018
    size the replacement by the btu Rating, not necessarily pipe size
    Also the valve needs to be mounted vertically 
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
    EdTheHeaterManilikebeans