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Tandem Oil Tanks

rrs26ja Member Posts: 4
I currently have a 275 gal oil tank. I just purchased a 330 gal tank that I would like to add in tandem. My plan is to use a 2" cross over from tank to tank and a 2" vent from the second tank. The 275 has what looks to be a 1 1/4 fill into a device with the gauge on it. Can I leave this alone and plumb as I said above? Should I use two filters? The filter now is at the bottom after the firematic valve. I plan to use the same setup on tank #2 and then tie two lines into a tee and then one line out to the burner. Does all of this sound okay? Will there be an issue having a 275 gal and a 330 gal hooked together? Thanks in advance for your help.....Ron


  • Marz
    Marz Member Posts: 90
    In my opinion, you should really use 2 separate fill pipes. Crossover filling is a problem waiting to happen. Puts too much pressure on the first tank once its filled and spills over into the second tank. It would be easier to pipe in a separate fill and just tee the 2 1-1/4" vents together.
  • Brewbeer
    Brewbeer Member Posts: 616
    i agree, each tank should have a separate fill, I've seen too many tanks fail when over pressured. Using fill and vent pipes that are the same diameter is also a good practice.
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  • Kakashi
    Kakashi Member Posts: 88
    Not knowing how old and what the conditions the tanks are in would be scary. You could wake up to a pool of #2 in your basement.