I recently fixed an undersink RO system (don’t ask me how, intuition I guess?) and my boss was going on about an “air gap” in the faucet. I asked my dad and it just confused me. Still confused a week later. So now I ask reddit, what the heck is an airgap, how does it work?
In: Engineering
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Air is lighter than water, so if you have both in the same pipe, the air will wind up on top. You have to have a lot of water flowing to push the air out, otherwise the water just flows in the space under the air, meaning the pipe is only partially full of water and you effectively have a smaller pipe. If the air has nowhere to go, then you won’t be able to fill the pipe up any more. That’s fine if you’re flowing downhill under gravity, but if your pipe has to go uphill or over a hump, then the air can act as a constriction on the fluid flow. With enough air present, the fluid flow is completely choked off.
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