Under Kitchen Sink Plumbing

Under Kitchen Sink Plumbing

In this video, This Old House plumbing and heating expert Richard Trethewey shows how to plumb a double-bowl sink. Steps: 1. Turn off the water to the sink cabinet and remove the cabinet doors for easier access. 2. Attach a shut-off valve to a length of copper tubing. Tighten the compressing fitting using two adjustable wrenches. Repeat to make a second shut-off valve assembly. 3. Connect the shut-off valves to the hot- and cold-water supply lines inside the sink cabinet. Confirm that the valves are off, then turn the water back on. 4. Install the faucet spout and faucet handles to the countertop. 5. From inside the cabinet, connect the faucet’s hot- and cold-water supply lines to the shut-off valves. Carefully tighten each threaded connection with an adjustable wrench. 6. Apply plumber’s putty to the underside of each basket strainer. 7. Set the strainers into the drain holes in the bottom of each sink, then tighten from below with a wrench. Scrape away any excess putty from inside the sinks. 8. Connect a brass tailpiece to the underside of each basket strainer. 9. Dry-assemble the ABS drainpipe and trap. Cut the pipe to length with a plastic-pipe cutter. 10. Glue the drainpipes to each trap using ABS cement. 11. Install a mini-vent valve to the drainpipe. 12. Connect one trap to the tailpiece protruding down from the sink. 13. Measure and cut a length of brass drainpipe to extend horizontally from the second sink trap to the T-fitting above the first trap. 14. Connect the brass drainpipe to the traps. 15. Attach the dishwasher discharge hose to the port on the side of the drainpipe. Tighten the hose clamp with a screwdriver. 16. Twist open the shut-off valves and check for leaks. 17. Replace the cabinet doors.
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Under Kitchen Sink Plumbing

Finding a Leak Before you can stop a leak, you have to find its source. That can be tricky. Water that escapes your pipes can travel a long way before it drops onto your cabinet’s floor. Here’s how a drip detective tracks the source of a leak: Fill both bowls of the sink with lukewarm water, not cold. (Cold water can cause beads of condensation to form on the pipes, making it impossible to find the leak.) Then get under the sink with a trouble light. Dry off all the pipes and examine the seals around the basket strainers. If you don’t see any droplets forming, remove both sink stoppers and watch for telltale dribbles. Joints are the most likely source of leaks, but old metal pipes can develop pinhole leaks anywhere, especially in the trap. If you can’t find any leaks in the drain system, check the water supply lines that serve the faucet. Finally, check for “splash leaks,” spots where water seeps under the sink rim or faucet base. To find these leaks, use a rag to dribble water around the faucet and sink rim, then get underneath and look for drips.
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Under Kitchen Sink Plumbing

There aren't many reasons for changing out the drain pipes under a kitchen sink, but one of the most common is during a kitchen renovation when the sink is being replaced. The steps for installing the sink drain will depend on how different the new sink is from the old one, as well as what other components are being installed. In older homes, the new sink may not be a different depth than the old one, so some alteration of the drain pipes may be necessary.
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Under Kitchen Sink Plumbing

The pipes under your kitchen sink can look daunting, especially if you have two sinks, but replacing them isn’t difficult, even if you have little plumbing experience. The curved pipes, which are called P-traps, connect to the sink drain and waste lines by compression fittings, and you can often unscrew these without a tool. If you’re replacing your pipes because they are leaking, it’s important to check the alignment of the new pipes when you install them. If they are even slightly out of alignment, the compression fittings won’t seal, and the pipes will continue to leak.
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Under Kitchen Sink Plumbing

Steps: 1. Turn off the water to the sink cabinet and remove the cabinet doors for easier access. 2. Attach a shut-off valve to a length of copper tubing. Tighten the compressing fitting using two adjustable wrenches. Repeat to make a second shut-off valve assembly. 3. Connect the shut-off valves to the hot- and cold-water supply lines inside the sink cabinet. Confirm that the valves are off, then turn the water back on. 4. Install the faucet spout and faucet handles to the countertop. 5. From inside the cabinet, connect the faucet’s hot- and cold-water supply lines to the shut-off valves. Carefully tighten each threaded connection with an adjustable wrench. 6. Apply plumber’s putty to the underside of each basket strainer. 7. Set the strainers into the drain holes in the bottom of each sink, then tighten from below with a wrench. Scrape away any excess putty from inside the sinks. 8. Connect a brass tailpiece to the underside of each basket strainer. 9. Dry-assemble the ABS drainpipe and trap. Cut the pipe to length with a plastic-pipe cutter. 10. Glue the drainpipes to each trap using ABS cement. 11. Install a mini-vent valve to the drainpipe. 12. Connect one trap to the tailpiece protruding down from the sink. 13. Measure and cut a length of brass drainpipe to extend horizontally from the second sink trap to the T-fitting above the first trap. 14. Connect the brass drainpipe to the traps. 15. Attach the dishwasher discharge hose to the port on the side of the drainpipe. Tighten the hose clamp with a screwdriver. 16. Twist open the shut-off valves and check for leaks. 17. Replace the cabinet doors.
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Under Kitchen Sink Plumbing

Learn how to replace the P-trap underneath your bathroom or kitchen sink The curved pieces of drain pipe underneath your sink, commonly referred to as p-traps, do a lot of dirty work. Over time they leak, become corroded or get plugged with years of accumulated soap and grease. When replacing a P-trap, you should use the same type of trap you remove. Traps are made from ABS (black), PVC (white) or brass (either chrome-plated or natural colored). Traps come in 1 1/4 inch (standard bathroom sink) or 1 1/2 inch (standard kitchen sink) inside diameter sizes. Be sure to check so you get the right size replacement at your local store. In this guide we’ll show you how to replace a P-trap in a few easy-to-follow steps.

Under Kitchen Sink Plumbing

Able to withstand the abuse of normal activity. Under-sink drain pipes are going to get bumped from people storing items there. Children and rental-property tenants are more likely to abuse things around the home. I believe the casual bumping of drain plumbing explains why they often become loose over time, and this is worse with PVC than with metal, because PVC fittings cannot withstand as much tightening.
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Under Kitchen Sink Plumbing

Here’s how a drip detective tracks the source of a leak: Fill both bowls of the sink with lukewarm water, not cold. (Cold water can cause beads of condensation to form on the pipes, making it impossible to find the leak.) Then get under the sink with a trouble light. Dry off all the pipes and examine the seals around the basket strainers. If you don’t see any droplets forming, remove both sink stoppers and watch for telltale dribbles.
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Install The Disposal and Strainer Aaron Stickley Before installing any drain pipes, it is necessary to install the garbage disposal and basket strainer. Install the garbage disposal onto the desired side of the sink first, since this takes up the most space. On the other side of the sink (for two basin sinks) install a basket strainer. This is also a good time to install any other under-sink components such as a water filter or a ​hot water dispenser. Continue to 5 of 6 below.
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Before installing any drain pipes, it is necessary to install the garbage disposal and basket strainer. Install the garbage disposal onto the desired side of the sink first, since this takes up the most space. On the other side of the sink (for two basin sinks) install a basket strainer. This is also a good time to install any other under-sink components such as a water filter or a ​hot water dispenser.
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The curved pieces of drain pipe underneath your sink, commonly referred to as p-traps, do a lot of dirty work. Over time they leak, become corroded or get plugged with years of accumulated soap and grease. When replacing a P-trap, you should use the same type of trap you remove. Traps are made from ABS (black), PVC (white) or brass (either chrome-plated or natural colored). Traps come in 1 1/4 inch (standard bathroom sink) or 1 1/2 inch (standard kitchen sink) inside diameter sizes. Be sure to check so you get the right size replacement at your local store. In this guide we’ll show you how to replace a P-trap in a few easy-to-follow steps.
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Install the vertical flanged tailpiece onto the sink strainer first. Secure it with a slip nut slipped over the tailpiece and threaded onto the bottom of the sink strainerSlide the end of the continuous waste pipe into the side outlet on the drain tee fitting, then slide the assembly onto the sink tailpiece and garbage disposal drain pipe. Adjust the pieces as necessary, making sure the continuous waste has a slight downward pitch toward the tee fitting. Secure the slip nuts with channel-type pliers. These do not need to be over-tight; the plastic threads can be damaged if you use too much force.