A sink drain, like any other plumbing equipment, is vulnerable to breakdowns and often the home foreman is faced with the question of replacing the device. Its installation is a simple procedure, for the sake of which it makes no sense to invite a professional plumber.
We will consider in more detail how the drain for the sink is arranged and what nuances to consider when choosing a device. And also describe the step-by-step technology for assembling and installing the drain fixture.
Purpose and design features
The drain for the sink in the bathroom or kitchen with overflow is a curved design, the key purpose of which is to redirect excess water to the sewer, thereby preventing overflow of the bowl of the sink.
The device drain system bath is almost identical to the design designed for the sink.
At the time of flushing, water first enters the siphon cavity, from where it flows into a curved “knee” and moves towards the general drain
Structurally, the overflow overflow for a sink or sink consists of the following elements:
- water trap - It is a “U” -shaped element that performs a dual task: it prevents the smell of smell from the sewer and protects the drain pipe located below from clogging.
- drain pipe - made of corrugated or rigid plastic pipe and designed to redirect wastewater to the sewage system.
The main secret of the siphon functionality in its design. Due to bending, the water does not completely leave the pipe. Formed water lock and acts as a barrier to the penetration of sewer "amber" into the drain hole.
The simplest version of the siphon is a plastic structure assembled from nozzles of various configurations and cuffs with a diameter of 32-40 millimeters
Such structures are convenient in that in the event of clogging, it is not difficult to remove and clean them mechanically or chemically.
Want to install a more durable device that is not so afraid of clogging? In this case, it is better to purchase a design in the form of a sink overflow for a sink. It differs from traditional models in that it is equipped with an additional handset.
This device connects the hole made in the upper side of the side of the bowl with the drain system elements located in front of the siphon. Due to this, the overflow drains the liquid from the sink, thereby preventing overflow of the bowl.
The auxiliary tube, which acts as an overflow, can be made of hard plastic or bendable corrugation; it is fixed to the structural elements by means of a plastic clamp
On the outside, the drain hole covers the grill. It performs a protective function, delaying small debris and hair, thereby protecting the system from clogging.
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Overflow - a hole in the upper part of the sink, designed to drain excess water from the tank in case the owners forgot to block the water
A pipe is connected to the overflow hole, through which excess water is drained into the sewer. Overflow hole can be located not only next to the mixer, but also on the opposite wall of the bowl
On models with a bottom valve, the water in the overflow pipe rises to a common level. Having exceeded the maximum level, water overflows through the wall of the siphon and falls below the valve
In small sinks, sometimes overflows are not suitable, since these devices are not designed for long-term use
There are models with hidden overflow, which is a system of holes masked by a pattern or curly relief plumbing
In models with hidden and overflow, and overflow, you can determine their position by carefully looking at the device. Water fills the sink and at a certain height flows into the sewer through slightly distinguishable grooves around the perimeter of the bowl
In many types of designer plumbing, an overflow is not provided, since its presence spoils the idea and does not decorate the design. They are equipped with automatic drains with a bottom valve and a sensor. Upon reaching the limit level, the sensor is triggered, the valve opens automatically, all water goes into the sewer
In floor sinks, design works, table bowls, a drain-overflow device is attached to the product. Finding a replacement for a free sale of a similar device can be problematic, so when buying such plumbing plum-overflow buy in stock
Traditional overflow plum
The location of the pearl on the front wall
Drain valve overflow with bottom valve
Bowl without overflow
Design option with hidden overflow
Concealed sink with overflow
Design products without overflow
Floor-mounted washbasin
The main types of drain devices
There are several types of drain systems. One of the most common options is a design in which the drain is fastened by means of a large locking nut. This method of fastening can be found even in the bathrooms of houses built more than two decades ago.
Device classification
The drain siphon systems used to connect the sinks come in three types: bulb-shaped, knee-shaped and combined.
They vary in type of construction:
- Bottle or bulb. The main structural elements are two cylinders immersed in each other. A tee is installed inside the flask of the device, which distributes the liquid and forms a hydraulic damper.
- Trumpet. The main element of the two-turn design is the “S” or “U” -shaped bend of the pipe, which forms the hydraulic damper.
- Mixed Type Devices. In addition to the structural elements of the bottle structure, supplemented by two partitions, they are equipped with a corrugated hose.
In bottle-type devices, the effluent entering a siphon moves down the inner pipe of a smaller diameter. Having reached the bottom, drains rise through the cavity between the inner and outer cylinders and are discharged into the sewer pipe.
Bottle models got their name because of the oblong shape of the tank, which looks very much like this glass vessel
Bottle siphons are advantageous in that even with the rare use of a plumbing fixture, a water trap in the sewer system does not dry out for quite some time. This effect is achieved due to the fact that the output from the siphon is located approximately in the middle of the flask.
Many owners prefer bottle siphons and for the reason that if necessary, several drains can always be connected to them. For this, the design only needs to be equipped with an additional element.
Equipping the bottle siphon with an auxiliary fitting, you can always connect an additional nozzle from the washing machine to the drain system
Mixed type siphons have proven themselves in work. The corrugated siphon used in the arrangement of the drain structure of a mixed type is a modified version of a conventional curved tube.
The key difference between the pipe used in arranging the mixed type drain design is that it is not a rigid part, but a movable flexible hose
In contrast to the bottle and pipe versions, among the combined variants there are no models with sockets, and therefore overflow systems and household appliances cannot be connected to them.
Production Material Division
The sink sinks on sale, depending on the material of manufacture, are of two types: those made of polymers and those made of metal alloys.
Polymer products are famous for their low price and ease of installation. Constructions equipped with a corrugated pipe are conveniently adjustable in length.
But the service life of PVC structures is relatively short. And the sealing properties of the assembled structures leave much to be desired. Therefore, all the connecting elements without fail during assembly are equipped with rubber gaskets.
In an effort to reduce the risk of clogging of the inner walls of pipes from deposits of dirt, leading manufacturers in the creation of polymer products include antibacterial components
In terms of reliability and durability, metal elements of drain systems are more advantageous. Non-ferrous metal models: brass and bronze are most in demand in household applications. The strapping made of such materials often has a chrome coating, due to which it acquires a rather presentable appearance.
The only drawback of metal pipes is the tendency of the inner walls to trap and accumulate mucus and dirt, which can cause blockages.
To prevent the accumulation of mud deposits on the inner surface of the walls during the manufacturing process, manufacturers coat metal products with a protective chromium film.
Installation of metal structures is not particularly difficult. The hitch can occur only at the stage, if you need to shorten the outlet pipe.
Siphons for non-standard equipment
For non-standard models of double “twin” sinks, siphons equipped with two outlets are used. Such siphon devices are connected to the drains of both sinks, and a little lower along the flow of waste water they are combined into a common flask.
As with single models, the design of the siphon devices of the drain systems with two outlets can be tubular or bottle type
Do you need to connect a sink placed on an open shelf to communications? Then choose a model that involves hidden installation. Yes, for the price it will be slightly more expensive than traditional options, but it will completely hide the unaesthetic elements of communications.
In addition to D32 / 40/50 mm corrugated pipes, universal products equipped with a stepped end of the spout can also be found on sale, which can be conveniently adapted to any size
Drain systems of such structures will not be difficult to hide in a niche, covered with a decorative screen. But it is worth remembering that if the bend of the outlet pipe turns out to be too short, the risk of an unpleasant sewer “aroma” is great.
Overflow drain technology
There is nothing complicated in establishing a drain overflow on your own. In the kit, each device usually comes with instructions. It contains information about in what sequence you need to assemble the structure.
The easiest way will be an independent master who installs a sink with an overflow channel provided for in the design of the sink:
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Stage 1: Assembling and connecting the drain pipe
Step 2: Install a nozzle to connect the drain to the siphon
Stage 3: Connect the siphon to the sink drain
Step 4: Tighten the plastic nuts by hand
Step 1. Preparation of necessary materials and tools
With all the variety of models of drain equipment, the technology for installing siphons is almost identical. Therefore, even if a drain system, for example, a bottle type, was installed on your plumbing fixture, you can easily replace it with the same combined version.
Regardless of the design, any discharge works according to the principle of two communicating vessels: at the upper point there is an inlet pipe that receives the spent liquid from the sink, below it is a drain hose that leads it to the sewer, and between them there is a water seal
The following items are included in the standard siphon package:
- device body;
- branch pipe;
- decorative slip overlay;
- plastic and rubber cuffs;
- connecting nuts and screws;
- rubber flat gaskets.
To better understand the sequence in which you need to assemble the structure, lay out all the elements of the siphon on the table or on the floor.
For work with plumbing equipment (sealing compounds) it is best to choose a semi-liquid sealing compound on a silicone or rubber basis
Installation of the system will not be possible without a set of necessary tools.
To work, you will need:
- flat screwdriver;
- adjustable wrench;
- FUM tape;
- sealant;
- capacity for collecting water;
- cotton fabric.
If during the work you need to cut pipes and corrugations to the desired size, prepare roulette and hacksaw in advance. For grinding the edges of the pipe - sandpaper.
Step # 2. Dismantling the old siphon
To remove the siphon device that has expired, it is necessary to unscrew the centrally installed screw in the grate located in the drain hole.
Often, the screw and nut of the drain grate “stick” to each other during operation. If they cannot be unscrewed in any way, first dismantle the lower part of the siphon, leaving the upper pipe intact. By rotating this part, you will help loose a dry nut and screw.
Having dismantled the old equipment, it is necessary to clean the inner cavity of the sewer pipe, removing from it the remains of dirt and crumbled cement
From the moment of dismantling the old siphon to the start of connecting the new equipment, it is better to “plug” the sewer socket with a rag or cork of the appropriate size.
Step # 3. Assembly of structural elements
When installing a pipe drain system, assembly of the structure can be performed during the installation process, sequentially "stringing" all the elements. If you have to work with a flask-like system, before you collect such a drain for the sink, you need to carry out a number of preparatory work.
First of all, the device is placed under the bowl and preliminary fitting is carried out in order to make sure that the sizes are consistent. After that check the reliability of fastening the bottom tube.
To do this, unscrew the plug by thread and inspect for chips and other defects of the rubber seal. Neglecting this step is not worth it, since the lower plug constantly takes over the pressure of the system.
Before assembling the structure, it is also necessary to check the mating surface of the body thread for defects and burrs
If burrs are found on the surface, they can be cut with a sharpened knife. If not removed, they may damage the O-ring during installation.
After making sure of the quality of the installed gaskets and threaded connections, proceed to the assembly of the bulb.
The work is carried out in several stages:
- Putting on the thread of the device rubber gasket, screw the bottom.
- At the ends of the spout tube, put on the gasket, and on top on a long nut.
- Having inserted the end of the spout tube into the hole in the upper part of the siphon body, fix it in a predetermined position by tightening the nut.
- Equipping the device cover with a rubber gasket, the drain is screwed with a nut to the body.
To improve the reliability of the connection, the annular gasket embedded in the groove must be coated with a sealing compound. It is also worth covering the lower part of the threaded connection.
In order to be able, in case of repair work, to easily unscrew the device cover at the joint of the case when sealing the connection, make the plumbing winding with an FUM tape
After that, the sink is installed on the seat and proceed with the installation of the drain device.
Step # 4. Features of overflow assembly
When dealing with models equipped with overflows, before assembling this element, you need to determine the height of the tube. This parameter should correspond to the depth of the bowl. If everything matches, the tube is connected at a given height to the main pipe.
If the overflow tube is a prefabricated structure, then its height is easily adjustable according to the principle of telescopic extension. The corrugated pipe simply stretches to the required length and bends in the right place.
Before tightening the screw, make sure that the outlet of the overflow tube exactly matches the hole provided for its installation in the side of the bowl
When fixing the overflow pipe to the sink, be sure to lay the included rubber gasket between the surfaces. The connection point of the outlet with the overflow pipe is fixed with a clamping nut. In order not to damage the connection, tighten the nut by hand, without applying special effort.
Step # 5. Mounting the drain device
Before connecting the assembled structure to the waste system, the surface of the sink in the area of the drain hole is thoroughly degreased and cleaned. During installation, the first thing they combine with the drain hole of the bowl is a protective grill equipped with 5-6 divisions.
If the diameter of the drain hole and the size of the grill match, it is enough to install a gasket, if there are small differences, an additional sealant is used
The upper end of the branch pipe is equipped with a rubber gasket and docked with a hole in the sink. Firmly pressing the upper side of the nozzle to the drain, fix it with a D6 mm screw inserted into the protective grill.
The thread into which it is to be inserted is pressed into the body of the pipe itself. When tightening the screw with a flat-blade screwdriver, it is important to achieve a tight fit, while avoiding turning the flange and gasket.
The chamfer is removed from the lower end of the pipe. This is necessary in order to ensure free winding of the end of the nozzle into the siphon cavity.
A plastic coupling nut is "strung" onto the branch pipe, placing it with the thread down, and the conical gasket, laying with the wide side to the nut. Then they dock it with the outlet pipe, not forgetting to seal the connection.
To fit the outlet pipe with a sewer pipe, the diameter of which is traditionally 50 mm, an installation rubber sleeve is used.
So that it tightly grips the pipe, thereby preventing the spread of sewer "aromas", use a product whose inner diameter is slightly less than the outer diameter of the outlet pipe.
If you use a soft corrugated pipe, make the length of the horizontal sections so that during operation they are without tension, but also do not sag
Tip: if the diameter of the outlet does not match the size of the sewer pipe, use a ready-made plastic adapter.
The corrugated siphon is as simple as possible to connect. It is equipped with two rigid nozzles at both ends. To connect it, you just need to attach it to the exhaust pipe, then stretch it a bit and give the desired bend. After this, the second branch pipe to the sewer.
Step # 6. System Health Check
At the final stage, it remains only to check the tightness of the joints and the operability of the system. For this, a section of the floor under the siphon is covered with a piece of cotton napkin or a paper sheet. Some masters for this purpose substitute a container under the siphon.
They open the faucet and watch how the water escapes into the drain hole and, passing through the siphon, falls into the sewer.
If there are no leaks at the joints and no drops appear on the napkin, the work is done efficiently. If they are found, tighten the nuts tightly, and the connection is additionally sealed.
The installation technology of branched siphons, which allows connecting washing machines to a common drain, is practically no different. The only difference is that flexible hoses coming from household appliances are additionally screwed to the design bends.
For those who plan to install and connect a new sink to the sewer, we recommend that you read the article Installing a sink in the bathroom: installation instructions for modern models
Video review of how to properly collect a siphon:
Sink installation and drain connection:
Modern models of sink drain are not so difficult to install. The main thing is to correctly select a model that is optimal for specific conditions, and strictly adhere to the installation instructions.
To all those interested in the matter of installing a sink drain, we suggest leaving comments and asking questions. Please share your personal experience in connecting plumbing. The contact form is located in the lower block.