Pressurized supply in, gravity drains out, and a vent stack that keeps it all flowing. See the whole water path through your house.
Your plumbing is two separate systems meeting at every fixture. The supply side delivers clean water under pressure — no pumps needed in the house — splitting into cold lines and hot lines fed by your water heater. The drain-waste-vent side works by gravity alone: used water falls through sloped pipes to the sewer, while the vent stack lets air in so draining water doesn't siphon the protective traps dry.
Tap any numbered part to learn what it does and how it fails — or press play to watch a full cycle.
The P-trap under that floor drain or sink has likely evaporated dry, breaking the water seal that blocks sewer gas. Run water in every fixture for a minute once a month — that alone fixes most "mystery sewer smell" complaints. If the smell persists in a bathroom you use daily, suspect a blocked vent or a failed wax ring at the toilet instead.
Close the nearest shutoff — under the fixture if it has one, otherwise the main valve — then open a low faucet to drain pressure. Water damage is a race: drywall and flooring are usually salvageable in the first hour, rarely after a day. This is exactly the scenario where knowing your main shutoff's location beforehand pays for itself.
Yes, and for different reasons. Wipes don't break down like paper — they snag on any rough joint and build the mats that block main lines. Chemical openers generate heat that damages older pipes and rarely clear the actual blockage; they just burn a channel through it. Mechanical clearing (auger or hydro-jet) fixes the problem instead of postponing it.
The breakdowns we see most, the symptoms that give them away, and the smart first move for each.
The symptom: A water bill that creeps up, warm spots on floors, a meter that spins with everything off.
Smart move: Shut off the main and confirm the meter stops; if it doesn't, the leak is between the street and the valve. Either way, get it traced before it becomes drywall work.
The symptom: The same sink or tub slows down every few weeks despite plunging.
Smart move: Repeat clogs mean a partial blockage or bad pipe slope deeper in the branch. A camera inspection finds it once instead of fighting it monthly.
The symptom: Multiple fixtures back up together; the lowest drain (basement or tub) fills when the toilet flushes.
Smart move: Stop running water immediately — everything you use comes back up. This is a main-line problem and needs professional clearing.
The symptom: A fixture valve or main valve that won't turn or doesn't fully stop flow.
Smart move: Have seized valves replaced during planned work, not during an emergency. Quarter-turn ball valves are the modern fix.
Every part in the diagram above is exactly what a My Happy Home membership exists for: when it breaks, a vetted expert fixes it — for one low monthly payment, with no hidden fees.
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Cold water down the dip tube, heat at the bottom, hot water off the top — and a sacrificial rod quietly rusting so your tank doesn't have to.
ExploreRefrigerator, dishwasher, laundry, disposal — four machines, four diagrams. Tap through each one to see what's inside and what wears out.
ExploreFollow the power: through the meter, past the main breaker, into branch circuits — and the safety layers standing between electricity and everything you love.
ExploreMembership covers the repairs on every system you just explored — one low monthly payment, vetted experts, no hidden fees.
