Plumbing Full course part 30

In this part of Full Plumbing Course, we are going to learn about, Vents and Venting.

Fixture Vents in Plumbing

Fixtures venting is a method of exhausting air from plumbing pipes. Fixtures venting is commonly used to prevent water build-up in drainpipes caused by condensation. Fixtures venting may also be used in conjunction with low-flow plumbing fixtures (e.g., toilets) to reduce water usage. In some cases, fixtures vents are used to provide additional drainage space for pipes that have been damaged due to construction or maintenance.

There are 2 types of fixture vents - Horizontal Vent & Vertical Vent. Here is a quick guide to understand them.

Horizontal Vent: A horizontal fixture vent is installed directly over a drainpipe where the outlet pipe meets the wall stud. The vent is angled downward and is normally fitted into a plastic sleeve.

Vertical Vent: A vertical fixture vent is placed between two ceiling joists. The vent is installed horizontally and is normally fixed in place using a metal bracket.

The above diagram shows how a horizontal vent works. The vent is installed at the bottom of the sink hole (i.e., the opening that drains into the sewer line). Water flows down the pipe and hits the top surface of the vent. Since the vent is open and exposed to air, it causes the air pressure inside the pipe to create suction. As the water level rises, the air pressure inside the sink hole decreases, causing the water to exit out of the sink hole through the drainpipe.

This process repeats until the water level reaches the depth of the fixture. At this point, the water fills the sink hole and overflows out of the fixture.

Since the horizontal vent creates suction, it is not recommended for use with high-volume sinks. High-volume sinks tend to draw water right up to the edge of the sink hole and cause the water to overflow before draining completely.

To avoid this problem, choose a low-profile or no-profile fixture. These types of fixtures do not take up much room and allow the water to flow freely without getting stuck before being drained completely.

A common mistake people make while installing fixtures is putting the vent too close to the drain pipe. If the vent is too close to the pipe, it will not work properly. The vent should be at least 1 inch away from the pipe.

Another common mistake is placing the vent upside down. The vent should face downwards toward the ceiling. When the vent is facing upwards, it becomes difficult to create a siphon effect.

Fixture Trap Design

Fixtures Traps are commonly used in plumbing systems, where water passes through pipes before reaching fixtures (e.g., faucets, showers). A fixture trap is a U-shaped pipe fitting that fits over a sink drain. The purpose of a fixture trap is to prevent sewer gases from entering the room and becoming trapped inside the bathroom wall. To do this, the fixture trap drains into a separate sewer line. If the drainpipe becomes blocked, the fixture trap prevents any sewage backup into the house. However, if a toilet fills with water and overflows, the fixture trap does not automatically shut off. As a result, sewage may flow out of the fixture trap and back into the house.

A fixture trap is a device designed to prevent water back flow in plumbing fixtures. These devices are present at sink faucets, shower/tub outlets and pipe connections. Most residential plumbing systems have three types of fittings. A single-handle faucet connects directly to a supply line. A two-hole sink tap has one handle, while a four-hole sink tap has two handles. Double sinks have two taps connected together. Each fitting has its own fixture trap. If the fixture had been fitted with a single handle or double handle, then only one fixture drain would be provided. If the sink was fitted with a four-hole tap, then four fixture drains would be present. In either case, each fixture drain has a fixture trap installed. All fixtures traps should be protected from clogging due to soap, hair, food particles and dirt accumulation.

Types of Fixture Vents

The type of fixture vent system you choose should depend on what kind of plumbing fixtures you use on your home. If you have copper pipes then open-ended ductwork would work best. If your plumbing fixtures are plastic or PVC, you'll want to look at either a straight-through or closed-end system.

There are two types of fixture vents commonly used in plumbing systems. Open-ended ducting is the most common style of plumbing venting. In open-ended ducting, the exhaust air travels through an opening at the top of the wall where it exits the house. Open-ended ducting works best if the area where you're installing the fixture is directly above the ceiling. There's no need for an attic crawl space here because the exhaust air simply moves out the top of the wall.

Closed-end ducting is less common than open-ended ducting, but it does provide some advantages over open-ended ducting. A closed-end system puts the exhaust air inside the wall cavity instead of outside the wall. This means that it doesn't escape via the roof, making it more secure. Furthermore, a closed-end system lets you install the plumbing fixture in a lower location, closer to the floor. Placing the fixture low enough makes the room appear larger without having to raise the ceiling.

Wet Venting

Why do we need wet venting?

While plumbing systems may have been constructed using PVC pipe, they still require periodic maintenance and repair to ensure proper operation. In some cases, water leaks occur due to improper installation, age, or damage to the piping system. If these leaks go undetected, mold can develop around the leak point.

What does wet venting do?

Wet venting helps prevent moisture buildup inside plumbing pipes. When air enters the pipe, it absorbs moisture, which causes it to expand. As a result, the pipe swells and exerts pressure against the wall. Over time, this repeated swelling and contraction can cause cracks in the pipe’s coating. As these cracks become larger, they allow water to enter the pipe.

How does wet venting work?

The term “wet venting” refers to a plumbing technique where a small tube called a dry-pipe valve is installed in the drain line at the sink or bathtub. Water entering the line is drained out through the valve, thus preventing water build-up in the area behind the valve.

What are some alternatives to wet venting?

In most cases, an alternative solution would mean replacing the existing plumbing system with a new PVC system. However, this option is usually not feasible because of the expense involved. Wet venting is a simple way to keep your home plumbing in good working order. While some people prefer to use dry venting, it is often recommended to install wet venting in place of dry venting.

Circuit vents are useful in plumbing systems where water runs through pipes. Circuits venting provides an air gap between pipe and fittings to prevent condensation buildup inside plumbing fittings. This type of vent prevents the formation of limescale and corrosion.

Circuit vents may be located anywhere along the piping run. A typical circuit vent consists of a thin-walled steel tube with a threaded or flanged fitting at both ends. A valve assembly allows you to turn off water flow.

There are different types of circuit vents depending on the location they are installed:

• A single circuit vent fitted between two pieces of pipe.

• Two circuit vents fitted the end to end with adjacent pieces of pipe.

• Three circuit vents fitted the end to side with adjacent pieces of pipe. These three types of circuit vents should be used only if two of the circuit vents cannot fit around the entire circumference of the pipe.

• One circuit vent is fitted between two fittings; the second vent is placed directly behind the first fitting.

• Several circular vent assemblies are attached together with several short sections of pipe running parallel to each other.