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OSV and residential Riello F40

Mike M
Mike M Member Posts: 34
I recently changed out my oil tank and removed the vinyl covered copper 3/8 line with a 3/8" orange line and a Garber screw on filter after the ball valve and Fire-O Matic . I said what the heck, and installed a 90 degree Sundstrand OSV with the red button on top, instead of the Webster style that requires an Allen wrench to over ride the OSV when required.  I had about 10 gallons in the new tank and all ran fine.  I filled the tank a few days later and the OSV on this gravity fed single pipe system shut down. The OEM said The Riello pump will not pull 3" of vacuum (the required suction to overcome the OSV.  I thought all single stage pumps could pull 6" of vacuum.... They told me I must remove the OSV or convert to a two pipe system, or Tiger loop, or a day tank...Have others run into this problem???   I asked him why it ran with only 10 gallons to which he replied the small amount of oil wasn't enough to close the OSV until the oil level reached enough force to close it.   Your thoughts???? Am I getting yanked around???


  • STEVEusaPA
    STEVEusaPA Member Posts: 6,505
    edited November 2013
    How many website forums....

    You posted...

    "...Am I getting yanked around???"

    Are we?

    How many website forums did you post this question? I count 3

    There was an error rendering this rich post.

  • Weezbo
    Weezbo Member Posts: 6,232
    Mike , there are parts with qualities that are quality

    and Riello F3 5 10 15 20 ,

    and a host of other oil burner two stage made by Riello.

    this might not have been our choice of oil valves ahead of the burner.

    however , i have no idea what qualities this osv has or if it even is what you think it is , i am not entirely certain that the burner is even what you are saying it is .

    an F -15 has like 11. something vac it pulls.

    and remains functional .

    i have installed an F-5 in a 215 Buderus bumped up the pressure to see the bottom of a F-10 with , a WoG to a general with a different platted filter than the one it comes with ( because i do not want the woll stuff finding a home in the Garber with the vac gauge installed on the top that comes after that filter ...from there it heads to the osv that holds the weight of the oil incheck as it were , then to a oil melt down valve into a tiger loop combo ...

    no problemo .

    the osv makes certain the oil is "There" not all over the basement floor should something go wrong , the melt down valve positively shuts things down if a fire somehow ensues near the boiler .

    it sounds like over kill to triple filtrate i know . buh lets just say ,

    i can live with that.


    i have different strategy for above ground tanks , i put things outside of the building at that tank as well.

    and maybe do away with the Garber . the vac gauge though is a definite plus ...

    the Tiger loop combo i prefer over the super duper graand delux ..because i can see inside the bowl and go ok so dummy me manage after puting red arrows with a marker on the supply side and blue one on the return managed to Still get the lines backwards lol..

    sorry , i ought not tell you this stuff..buh it is something that i can live with ..

    any way , ... you have a Mercron ?"




    mah memory is coming back to me lol..

    i always spell things poorly it seems and have to go back and check my spelling ..sorry .

    the old Riellos i am losing sight of in my minds eye ...

    my apologies , i think i worked on one three years ago maybe two.

    took me two days to simply clean the Buderus it was bolted up to.

    anyway , i dont go by memory on these things that i worked on in my 30's thats three decades ago and so i look them up like everyone else.

    the threads i found were while i was looking to see what i am missing in this conversation .


    maybe thats the reason you are having oil problems ... its the pinner oil filter ....

    Hope that helps ...
  • Mike M
    Mike M Member Posts: 34
    multiple postings??

    only two, got lots of views here but no responses
  • Mike M
    Mike M Member Posts: 34
    edited November 2013
    Riello burner

    The burner is a Riello 40 F5 mounted to a 4 section Pesotti I think SI-26.

    Installed originally in 93 and I have no prefilter.  I was thinking of installing one of the wooly filters to remove the rocks and bolders so the Garber didn't have to be changed as often but The OSV on there is made by Sundstrand. To over-ride a Webster you need the special tool they make or a small allen key.  The Sundstrand is so much easier, It has a small red pin you depress to temporarily bypass the OSV.  In an article on another site an author of a magazine article said it used to be called a PRV till Webster started making them and decided to call them an OSV. The unit runs now because I have a clamp on the pin, till I can figure this out.
  • Weezbo
    Weezbo Member Posts: 6,232
    Maybe thats right

    where i recall prv's ,

    were to protect like 15000 gallons from the day tank flooding the building ...

    the Webster well that doesnt take much to tweak , a paper clip , after a shut down and your in business . the Sundstrand that you have might work with out holding the red button down continuously .... did you try that ?
This discussion has been closed.