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275 gallon tank piping question

hh409 Member Posts: 14
the installation on a 275 gallon heating oil tank in the basement started but its not yet complete. as every professional has a technique that's a bit different i had a few questions concerning the installers methods.

1)concerning the fill pipe

the length of the pipes from the tank to the house exit is appx 5 feet.

how much should the fill pipe be pitched? of the two pipes installed but yet to be designated one is pitched about  1/2" in 5 feet and the other about 1" in 5 feet.

also how should the little 45deg. fill elbow with cap be positioned? can it be attached directly to the horizontal end of the 5' long fill pipe or should a short vertical rise/nipple be attached first.

the technician plans to make the fill pipe higher than the vent pipe, that will put the fill at about 48" seems a bit too high for me.

2)the 12 gauge single walled tank is slightly pitched towards the bottom valve, the level vial is slightly cracked, i assume this is enough??

3)in a prior post several respondents mentioned the use of "swing joints" to alleviate settling upon fill. here they were not used but are not code. are these critical?

4)the burner is currently set up with two lines a feed and return, should the new tank be piped the same way or is the return not needed? why do some burners have a return and others not?

i definitely want to be present for the first filling

the installer works under a licensed plumber and seems qualified however there are still variations between a professional who does 3 tanks a month and one who does 3 a year, which is why a ask for your opinions. that said i have a tendency to "over analyze everything"

if there are any critical points i need to be aware of please let me know.

thank you


  • billtwocase
    billtwocase Member Posts: 2,385

    Your 1st section of question have me baffled. Is it a total of 5 feet up and out of the building, or 5 feet out? Secondly, a fill should never be piped higher than a vent, in case of overfill, etc.   2nd, the pitch should be slight only. That is enough to direct any condensation to the outlet. Any more than that, it will end up in the far corner, and stay trapped.   3rd swing joints are a good idea, but only code here for underground, or flood zone.  4th is to have it set up as one pipe. That is all you need, especially when it will be gravity fed.  As usual, it needs to be installed to code, and inspected. All shut offs, manual and thermal, should be present, a protected/secured fuel supply line, vent alarm, gauge, an approved filter, and flare fittings to name a few. These are mostly Mass rules, which are among the best. Where are you located?
  • Paul48
    Paul48 Member Posts: 4,469

    Fill and vent of equal size.
  • icesailor
    icesailor Member Posts: 7,265
    Pipe Pitch:

    It sounds like the vent and fill will have different horizontal pitches?

    That would look to me like some hack dubber piped it.

    Swing joints are convenient for going from horizontal pitched pipes to vertical plumb pipes. I always make "crooked threads" so I can switch back to plumb.

    The fact that someone pipes a lot of oil tanks for a plumber tells me that the "plumber" doesn't like to pipe oil tanks or he doesn't own a power drive and doesn't intend on acquiring one.

    The only way I would not pipe an oil tank on a job of mine would be if it was already there and existing. If it is a crappy install, I wouldn't want anyone to think I installed a mess.
  • billtwocase
    billtwocase Member Posts: 2,385
    vent pipe size

    yes Paul equal to or larger than the fill, and 1-1/4 would be the the nor.m. There are quite a few requirements for tank installs here.
  • Paul48
    Paul48 Member Posts: 4,469

    Old tanks have been burst in basements by a driver using fast-fill on an old tank with a small vent.
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