TRAPS & SOVENT

A fixture trap is a device scientifically

designed to prevent the backflow of gases into the outlet of the fixture.

Trap seal – the column of water that is retained between the overflow & dip of the trap. Also known as “Water Seal”.

Traps

Water sealed traps are classified as:Permissible Traps and as Objectionable Traps

1. The P-Trap/Gooseneck 2. The Drum Trap

The Permissible Type of Traps are:

Attributed to its form that is in some manner

as the neck of the goose. P-trap is used to provide a mechanical barrier against passage of noxious air form the septic tank or main sewer line.

The Water-Sealed P-Traps Classifications:1. The common seal P-Trap2. Deep Seal P-Trap

The P-traps/Gooseneck

A common seal P-Trap is used for fixtures that

are subjected to normal conditions. This trap has 5 cm deep water seal.

What is a common seal P-trap?

A deep seal P-Trap has from 7.5 – 10 cm water

seal content. It is purposely designed for situations such as:

a. Extreme heat condition in the area.b. Increase/decrease in atmospheric pressure.c. Circumstances where total ventilation is

unobtainable.

What is a Deep-Seal P-Trap?

Re-sealing is the term used to the scientific

principle that water at rest tent o seek a level & maintain it.

One advantage of the Deep Seal over the Common Seal traps is its greater re-sealing quality.

The P-Trap is the most common and practical

shape available in various sizes from 32 - 150 mm in diameter. These are suitable for fixtures such as:

1. Lavatories2. Sinks3. Urinals4. Drinking Fountain5. Shower Bath with less amount of discharge.

Common P-Trap operated fixtures

1. Stand Trap

2. Brass Trap

3. High Hub Trap

4. Low Hub Trap

5. Extra Heavy Type

6. Sink or Lavatory Type

Some other types of Permissible Traps:

1. The full size S and the ¾ S Traps.

2. The Bag Traps.

3. Mechanically Sealed Traps.

4. Light metal partition traps.

The objectionable traps which are found defective

includes:

1. All traps shall be self cleaning.

2. P-Trap should be installed as near the fixture as practical. Short vertical leg eliminate high velocity of water discharge which create siphonage.

3. The P-Trap should be installed within 60 cm of the fixture and accessible for cleaning through the bottom opening closed by a plug. All traps are subject to stoppage, hence, should be provided with cleanout or be designed that could be disassembled with little efforts.

The National Plumbing Code on P-Trap Installation

provides that:

4. Long run of horizontal pipe called running trap could be used

only near the drain of the floor area or yard and not provided with hand-hole cleanout.

5. Overflow pipe from fixture should be connected into the inlet side of the Trap.

6. The dip portion of the trap should be as short as possible to avoid retarded flow of water. Likewise, the horizontal leg connection to the waste pipe must be short for effective ventilation.

7. That, each fixture trap shall have its own trap.

The following are exceptions to the rule:

a. Two laundry trays and a kitchen sink connected to a single trap.

b. Not more than 3 laundry tray using one trap and

c. Three lavatories on a single trap.

The drum trap derived its name from

its form and size being large in diameter.

1. For fixture that are set on the floor such as bath tubs, foot & sitz bath, etc.

2. For fixtures that discharges substantial amount of water wherein trap-seal loss is more prevalent.

3. Used as terminal for soda fountain, bar wastes and any type of indirect waste.

4. Designed in two types(a. 100 x 125 mm, b. 100 x 200mm)

Drum Trap

Advantages

1. Greater amount of water may pass through it in a shorter interval without danger of trap seal loss.

2. It has a higher re-sealing quality than the P-trap.

Disadvantages3. It is large and cumbersome4. It is unsightly if the installation is exposed.5. The cleanout mechanism is above the water seal.6. To clean the drum trap need lubricant and a fiber washer

in the joint between the cove and the body of the trap.

Advantages & Disadvantages if Drum Traps

The National Pluming

Code has regulated the minimum diameter of traps and drain sizes to be installed depending upon the class of user for which the installation is to serve.

1. Class 1 – For Private Use applied to fixtures in

residences, apartment and private bathroom of hotels and etc.

2. Class 2 – For Semi-Public Use applied to fixture in office buildings, factories, dormitories and etc.

3. Class 3 – For Public Use such as schools, gymnasium, hotels, railroad and bus terminals, public CR’s and etc.

Classifications of fixtures to be installed:

The House Trap

House Trap is a device installed in the house drain that act as barrier to prevent the gasses from the public sewer line or septic tank in circulating through the plumbing system of the house.

A Floor Drain is a receptacle intended to

receive water from the floor & convey into the plumbing system. Floor drain is usually installed on:

a. Basement floorb. Near the heating equipmentc. Below the kitchen sinkd. Vicinity laundry

Floor Drain Installation Recommendations:

2. Every floor drain should be supplied with running water from a fixture nearby.

3. The 75 mm (3”) P-Trap is recommended for floor drain. It should be installed not more than 30cm below the floor line.

4. The trap should be Deep Seal type.5. The trap may be of low inlet hub pattern.

It is a device installed on plumbing system

serving kitchen of hotels, dining rooms, clubhouses and restaurant.

Grease Trap

1. The grease trap should be installed as close

to the fixtures as possible.2. More than one fixture can discharge into the

same trap provided that the trap has sufficient pipe size and the waste pipe is not very long.

3. Earth-Cooled Grease Trap is used on large installation and is most desirable type.

4. The basin width should be not less that 60cm long.

Installation of Grease Trap

6. The minimum depth of concrete grease trap should not be less than 120 cm below the outlet invert.

7. The size of the grease trap is measured through the amount of fixture unit discharge.

Is a recent development in drainage

installation which is suitable for tall buildings. It almost completely eliminate the vent stack and other forms of ventilation with the same effectiveness.

Introduced in 1962 by Fritz Sommer of Switzerland, it was tested on a 10 storey drainage tower which has resulted in a satisfactory performance.

First used in the US in 1968 at the Uniment apartment in Richmond, Ca.

The Sovent System

Often referred to as

DWV, this system has been proven efficient plumbing system and universally accepted for years.

The two line system

1. The routing and re-routing of the various kinds

of vents.2. Additional cost for materials and labor.3. Space requirements.

In order to address this problems, a new concept of Plumbing System called Sovent System was introduced.

However, the incorporation of the vent pipe in the plumbing system although promoting efficiency in the installation services, has also brought some of the problems enumerated as follows:

1. A large amount of waste and sewage

discharges form the fixtures could form like a slug that presses the air downward the pipe and create two kinds of forces such as pressure and suctions.

2. The downward force, called plus pressure create back flow of water seal in the P-Trap of lower fixtures, while the suction force called minus pressure create siphonage inside the pipe pulling down the water seal of the fixtures in the upper floor.

Mechanics of the sovent system

3. The Sovent function is to change the solid

nature of the effluent by scattering them into drops or small blobs to fall like liquid in a shower.

4. Although the effluent rarely fills the soil pipe completely, still it has the action of a plunger.

5. In a single stack Sovent System vent piping is not necessary.

6. The Sovent action of reducing the positive and negative atmospheric pressure is done at each floor where the aeraor is installed.

7. The effluent that was already aerated falling down from the upper floor is diverted in the soil stack at each lower floor.

8. The areator spatters or scatter the effluent in drops or small blobs wherin they are mixed with the air forming a rarefied mixture of air and liquid.

9. At the bottom portion of the single stack, the aerated effluent is compacted.

10. The deaerator consist of

an air separation chamber with and internal nose piece, a stack inlet, a pressure relief outlet at the top and an stack outlet at the bottom.

Copper was the original material used for

Sovent systems. This is attributed for its proven record of quick, trouble-free installation.

Copper is also the material used for the Aerator and Dearator fittings.

The aerator is used as a terminal of the soil branch in each floor of a building while the deaerator is installed at the bottom portion of the soil.

Materials and Design