Comment on First time ever installing a water heater, or doing any plumbing...

• rockSlayer@lemmy.world ⁨1⁩ ⁨year⁩ ago

  An expansion tank is necessary for water heaters, because the process of heating water causes it to expand. Without a reserve tank, pressure could build to unsafe levels

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  • SpeakinTelnet@sh.itjust.works ⁨1⁩ ⁨year⁩ ago

    All tanks are equipped with a safety release for the pressure and the only time when that delta in pressure can be problematic is when you go from completely cold to hot due to the higher amount of water that can fit in the tank at lower temp.

    Otherwise I’ve never seen a house in Canada with an extension tank attached to the water heater and the water come in ice cold in the winter.

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  • falsem@kbin.social ⁨1⁩ ⁨year⁩ ago

    Pressure won't build up, it will be let out by the pressure relief valve and make a mess on the floor. Which is also undesirable.

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    • SheeEttin@lemmy.world ⁨1⁩ ⁨year⁩ ago

      Well, right up until the pressure relief valve fails. Whether it fails open or closed, you’re gonna have a bad time, because either way you’re probably going to have a lot of water where there’s not supposed to be water.

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  • AnotherPerson@lemmy.world ⁨1⁩ ⁨year⁩ ago

    If it’s necessary then how did my last tank make it 20 years without one?

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    • rockSlayer@lemmy.world ⁨1⁩ ⁨year⁩ ago

      Honestly, I don’t know, I’m not a plumber. There are a couple possibilities, including that it was built into the water heater or the relief valve did it’s thing. Some water heaters don’t need expansion tanks at all, either. It’s generally a “just in case” thing, since the right failures in the wrong way could lead to a hot water bomb going off in your house.

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      • AnotherPerson@lemmy.world ⁨1⁩ ⁨year⁩ ago

        Yeah but that was like the coolest mythbusters episode ever /s

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  • AnotherPerson@lemmy.world ⁨1⁩ ⁨year⁩ ago

    In reading it looks like it is for homes newer than 1986? Our old water heater was 20 years old and we never had any issues with the pressure getting to high.

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