Kitchen plumbing in Los Angeles for drains, dishwashers, ice makers and remodels

Kitchen lines carry grease, starch and coffee grounds. Grease cools inside the pipe, grabs food fines, and narrows the line a little more every week. The clog you finally notice is often ten or fifteen feet down the horizontal run inside the wall, not in the trap.

Older houses here often have galvanized kitchen drains that rust and scale on the inside, so the opening shrinks even without grease. A cable will punch a hole through that buildup, but it comes back. When a kitchen line clogs every few months, we look at cleaning the full run with water pressure using a jetting setup or replacing the worst section.

If several fixtures are slow at once, or the clog returns in the floor drain or a lower toilet, the problem is in the main line instead. In that case general drain clearing from the closest cleanout is the right first step.

Dishwashers are the leading source of kitchen leak calls. The supply connection at the valve, the discharge hose clamp at the disposal, and the door gasket are the usual spots. We use a braided stainless supply with the right elbow fitting, set a high loop or air gap on the discharge, and level the machine so water does not run toward the door.

Refrigerator water lines get the same treatment. We replace thin plastic tubing with braided line and add a dedicated quarter-turn valve where you can reach it. Swapping the sink or faucet at the same time? See how we handle a new sink and faucet. Pot fillers over the range need a supply run inside the wall, a valve you can shut off, and blocking so the arm does not loosen the wall.

Gas ranges connect with a coated flex connector and a shutoff valve behind the unit. If the range is moving, or the old connector is uncoated brass, we replace it and test the joints.

• Dishwasher supply, discharge and air gap
• Refrigerator and ice maker water line with its own valve
• Pot filler rough-in and finish
• Gas range connector and appliance shutoff
• Instant hot water dispenser and under-sink filter

An island sink is the most common kitchen layout change, and it is mostly a drain and vent problem. Water supply is easy to run. The drain needs a steady slope back to the stack, and the fixture needs venting, which is hard with no wall to run a vent pipe up through.

In a slab house we saw-cut the floor, trench to the nearest drain line, and lay new pipe at the correct fall. In a raised-foundation house we run the line through the crawl space, which is faster and less disruptive. The vent is handled with an island loop vent or another approved method, decided with the building department before we cover anything.

Plan the island plumbing before the cabinet layout is final. A few inches of shift can decide whether the drain reaches an existing line or needs a long new run. For a full room change, our page on remodel plumbing for baths explains how we stage rough-in and inspections the same way.

Wipe greasy pans with a paper towel before washing them. Run cold water with the disposal and let it flow a few seconds after the grinding stops so food fines clear the trap. Skip coffee grounds, eggshells and potato peels in the disposal, since they settle as sludge in the horizontal line.

Enzyme drain treatments help slow buildup in a line that is already clean. Caustic drain openers do not clear grease plugs well, and they sit in the trap and attack old chrome and galvanized pipe. If the sink is already slow, call us instead of pouring chemicals in.