Is it necessary to ground an instantaneous water heater? How to ground a water heater

For a person accustomed to comfort, the absence hot water even for a few hours it seems like a disaster. Huge variety of household heating devices, in conjunction with at an affordable price, make the purchase and installation of devices in a simple way solve the problem of hot water supply. However, during installation, inexperienced users, through negligence or ignorance, “forget” to ground the water heater.

Storage water heaters - boilers

What results from violating the rules for connecting to the electrical network, lack of grounding, and how to properly make protection against electric shock with your own hands is described in the article.

Why is a water heater grounded?

The water entering the water supply system is a good conductor, and electric heating devices in apartments and private houses operate on electricity. Regardless of the type of electrical appliance (flow-through or storage), the liquid comes into contact with the heating element.

Boiler contact group - yellow-green wire for grounding the housing

In case of burnout of conductors, destruction of the heater housing, contact of the phase housing with the housing, contact between water and the exposed wire cannot be avoided. The liquid becomes a conductor for leakage current. In cases where the user touches the ungrounded metal body of the device or exposes parts of the body to the flow of water, the electric current will flow along the path: 220 V phase - water heater water - human body - earth (through water). A noticeable impact, often resulting in death, is inevitable.

In another case, a potential difference may occur between two electrical appliances (you can often find the not entirely correct name “stray currents”) located in the same room. In this case, touching the devices at the same time also leads to a noticeable tingling sensation. Grounding in such cases serves to equalize the potentials of the circuits. In addition, the presence of “extra” potentials on devices accelerates their destruction.

Methods and principles of grounding

There are two different ways protection from defeat electric shock– protective grounding and grounding. Out of ignorance, authors often call them in one word, grounding.

What is the difference? In the case of “real” grounding, the metal body of the electrical device is connected by a separate conductor to a special circuit. We will tell you below how to make it in a private home or country house.

Block diagrams of grounding and grounding connections

In this case, the operating voltage that reaches the device is discharged along the following path: electrical installation housing - conductor - grounding bus - ground. According to the rules of electrical installations, the resistance of such a circuit should not exceed 4 ohms, which is much less than the resistance of human skin. Thus, all the current will go to the ground. If the current values are high, the circuit breaker will trip and the power supply to the consumer’s electrical installation (as electrical appliances are correctly called) will be turned off.

In case of grounding, there is an additional wire in the socket (painted yellow-green) and is called a PE conductor. The grounding wire in the heater is connected to dangerous parts of the electrical appliance, which can become a source of current leakage. In case of integrity violation heating element, when a phase hits the housing, the current will flow along the path: phase wire – device body (heater) – grounding protective wire – apartment distribution panel. If the rated current is exceeded, the protection device will operate.

The choice of grounding type for any type of water heaters in an apartment depends on the organized power supply circuit of the residential building.

How not to ground electrical appliances

There are several seemingly simple ways to organize protection in your apartment, but the use of which is strictly prohibited:

Connecting the third wire in the outlet to the plumbing or heating pipes running through the kitchen or bathroom.

Prohibited grounding to a water pipe

In case of phase breakdown on the heater body or washing machine all dangerous potential will end up on the entrance riser. A neighbor who opens the water is doomed to receive an electric shock. Moreover, this method does not work in case of replacing a part. metal pipes plastic analogues - “grounding” will not fulfill its function.
Combining the neutral and grounding contacts in the socket. A zero break in such cases leads to the appearance dangerous voltage on the buildings of all consumers connected to the apartment network.
Grounding of several devices in series one after another. If a fault occurs in one device, all others will be exposed to dangerous voltage.
Connection of several wires to one bus terminal. Each device must have a separate contact.
Independent production of grounding devices and connecting a bus to them. Such devices can disrupt the operation of the entire energy supply system at home and fail to fulfill their intended purpose at all.

Electrical wiring diagram of an apartment building

Until 1998, according to the standards in force at that time, most houses were powered using the so-called TN-C circuit or a circuit with a solidly grounded neutral.

A four-core cable was installed in the house, which had 3 phases and one neutral conductor. In an apartment, such a system is easy to identify - all sockets do not have a protective contact, they are two-pin.

In houses modern construction The power supply is supplied by a five-core cable (TN-S wiring), in which the working and protective neutral wires are separated. The sockets have a protective contact, just like when using the TN-C-S circuit. There are other grounding schemes.

Grounding organization diagrams

"The picture shows possible options power supply and grounding diagrams. If you do not have exact information about what kind of circuit is organized in your home, contact an energy specialist management company».

How to ground a water heater in an old house

In houses old building To organize grounding, you will have to perform a number of works and spend money on purchasing materials.

Purchase a single-core copper wire with a cross-section of at least 4 mm 2, which on one side is connected to the ground contact on the electrical appliance. The other end of the wire is connected to the bus in the interfloor panel. It is advisable to lay the wire in a groove to avoid damage. To connect, solder a contact to the ends of the wire to tighten it under the bolt.

Using an RCD

Another way to protect yourself from electric shock is to install a residual current device (RCD) or a differential circuit breaker.

The device is installed separately on the water heater or on the common electrical wiring input.

The essence of the devices, in short, is as follows. The device is installed in the gap of both conductors (phase and neutral), through which power is supplied to the premises. At normal conditions operation, the currents flowing through the phase and neutral conductors are equal. The power remains connected.

If a leakage current occurs through one of the wires, the values of the flowing currents will become different. A residual current device or differential circuit breaker will disconnect both conductors from the consumer.

RCD connection diagram

For installation in residential premises, provision is made for the installation of disconnect devices that are triggered by a leakage current of 30 mA. The response time of the devices does not allow you to receive an electric shock that is dangerous to health.

What to do in private houses

Any property owner can install an individual grounding system in a private home or country house.

Important! If there is not enough specialized knowledge, we strongly recommend that you contact an electrician from the village management company (the board of the dacha society). This will help avoid mistakes when construction work and when connected.

In any case, it is better to carry out the general construction part yourself - this will save a significant amount of money.

Construction part of manufacturing individual grounding

Manufacturing procedure:

Having retreated 1.5 - 2 meters from the foundation of the house, they dig a trench in the shape of an equilateral triangle with a side of 2 - 2.5 m. The depth of the recess is 60 cm, the width is 40 - 50 cm. Between the triangle and the wall of the house they also dig a recess for connecting the bus to the distribution shield.
At the corners of the triangle, pins made of metal reinforcement with a diameter of 12–14 mm are driven into the ground, leaving 5–10 cm above the bottom of the trench.
The driven pins are connected to each other by welding a metal strip 4 mm thick and 40 mm wide. The same strip, welded to the pins, is placed on the wall of the building.
The trench is buried.
Bolts with a thread diameter of 8-10 mm are welded to the strip placed on the wall - grounding wires from household electrical appliances (boilers, washing and dishwashers, various machines).
Single-core heater grounding terminal copper wire with a section of 4 mm 2 or an aluminum section of 6 mm 2 are connected to a bolt welded to the busbar. The connection is made “under the bolt”.

So, connecting household water heaters and other energy-intensive appliances to a protective grounding system is caused by the need to comply with safety regulations.

The device saves the lives of users in case of malfunctions of electrical appliances and minimizes the likelihood of fires. An easy-to-implement grounding system will help avoid tragedies when using electrical appliances.

From the author: We welcome you, dear friends! If you have ever been faced with the issue of buying a boiler, then you probably first of all thought about what power to choose. The second selection criterion is the volume of the boiler. Right? Home craftsmen start thinking about how to connect a boiler to electricity without grounding already when the water heater is delivered to the address. There is no desire to wait for the technicians to arrive, because I really want to connect the boiler as soon as possible and make sure it is in good working order.

Often, homeowners decide to install a boiler using video instructions, not because they do not have time, but because they save money. Let's assume that you already have experience conducting plumbing work, or some knowledge of electrical engineering. You will probably want to connect the boiler yourself, earning additional respect from your family. In this material we will consider in detail the algorithm for installing a water heater, taking into account the need for additional grounding and without it.

Basic connection methods

When ordering a boiler for home or commercial use, it is important to understand that, depending on design features This product, there are two methods for connecting it to the electrical network.

A water heater is a powerful consumer that operates simultaneously with water and electricity. Therefore, the boiler must be grounded without fail. Most apartments do not have it, since the buildings were built a long time ago. How to organize secure connection techniques, you will learn below.

It ensures stable and uninterrupted operation of the equipment. Main reasons:

Water is an excellent conductor of current. Since the boiler parts are in constant contact with moisture, grounding allows you to avoid many problems. If the integrity of the wires is broken, you may feel a small shock when you open the faucet or take a bath. This can be deadly. When one of the elements hits the body, an electric shock can occur upon contact.
Discharge of stray currents. They accumulate in the metal elements of the device and lead to corrosion of the tank and its parts. In addition, a person may feel a slight tingling sensation during use.
When struck by lightning in a thunderstorm, the ground will take the shock. This way your equipment will remain safe and sound.

How to ground equipment if there is no way to route the wiring into the ground? For example, in an apartment. Many turn to options that are contraindicated. Let's look at them in more detail to prevent problems.

How not to ground a boiler

It is prohibited to carry out the procedure using a heating riser or water supply. Firstly, this leads to corrosion and rapid deterioration of the pipeline. Secondly, you and your loved ones can get an electric shock when touching a boner.

Connect to mounting hardware. This leads to the same consequences as stated above.

Even if you installed a grounded outlet, this does not mean that everything is now in order. Without correct wiring The socket is ineffective.

On the forums they advise to do this: find the zero contact on the wire using a tester. Then connect this wire to the outlet terminal and the ground contact. This is how we get zeroing in the apartment. But for some reason, the “masters” do not take into account that when the zero is broken or switched, a phase may turn on in the panel. One touch of the device body will result in a fatal discharge.

How to make grounding

You can organize everything correctly with the help of our recommendations. Inspect the water heater and locate the ground terminals. All modern devices equipped with them.

Buy an outlet with three holes and a moisture-resistant casing, especially if installing in a bathroom.

Mount the outlet at a distance of 50-80 cm from the floor and the water heater.
You need to run a three-core copper cable from the panel to the outlet. If desired, you can embed the wiring into the wall by drilling a channel.
Turn off the electricity and connect the wires to the outlet. Their colors will help to correctly distribute the veins. See the picture below:
photo 4
Connect the ground cable to the busbar on the panel.

Some people use equipment without grounding. After heating the water, they disconnect the device from the network and begin operation. However, not everyone can remember this. In addition, the temperature settings are lost, and the storage device has to reheat the water, consuming electricity.

What to do in a private house

In the private sector or at the dacha, you need to organize grounding yourself. You will need skills to use welding machine. Also three metal pins (angles, pipes) 1.5 meters high and 15 mm in diameter.

Select a site 1.5 meters from the house. No one should go here in the future.

A trench in the shape of a triangle is dug at the selected location. Each side should not exceed three meters. A trench is also dug from the corner of the house.
Place one pin in each corner.
Weld M8 or M10 bolts to the top part.
Drive the pins into the ground until only the 5cm tip remains.
Choose a place on the wall of the house. It is better to choose a point at a distance of two meters from the shield and 10 cm from the floor.
Make a hole with a hammer drill.
Take a steel wire (6 mm) and connect it to the heater terminal.
Run the wire along the wall to the hole and then to the post outside.
Place a washer on the bolt and wind a coil of wire. Secure on top with another washer. Do this with each pin, then make a loop.
Fill the trench with soil and compact the surface.
Now measure the circuit resistance. Normally it should be less than 4 ohms.

All that remains is to connect the water heater, add water and start the test operation.

As you understand, grounding can be done both in Khrushchev and private sector. This is an important part of the operation of an electrical appliance. Watch the video to make it even easier:

25-05-2008, 03:39

We have a Khrushchev building where there is no grounding in the wiring. Is it possible to install a water heater in such conditions?
We read on the Termex website that it seems that connection without grounding is prohibited...is that true? Are we out of luck now?
...The flow-through did not work out due to the low voltage to the apartment, now there is no grounding....:(
How did you get out of such situations? Hot water is very hot! :091:

25-05-2008, 18:50

no one connected water heaters in Khrushchev houses and ships???:010: :(

25-05-2008, 19:19

I have had Ariston in my old stock for 8 years now
there is no "land" by definition
t-t-t, no incidents
I changed it under warranty (the tank was leaking), so this special attention no one complained and they changed it without any problems :)

25-05-2008, 19:33

I have it connected without grounding, my parents do too
nothing so far everything TTT is fine

25-05-2008, 21:08

25-05-2008, 21:12

I have an RCD and a storage heater :)

25-05-2008, 21:33

Grounding was “invented” in order not to receive a current discharge......You can install it without it......You live or don’t live.....Or you can connect it to a pipe, then it will either kill you or neighbor, it's up to you.........

Volodya Volodya

25-05-2008, 21:36

If you want to take your own life, you can do it without grounding. You can see about the connection here http://www.thermex.ru/prod_how2.php3?title=how%20to connect%20a water heater, and they also advise installing an RCD. “Perhaps yes,” they are bad advisers. There is a lot about water heaters and connections on the forum: http://forum.ixbt.com/topic.cgi?id=47:3666-24
and here http://www.ivd.ru/document.xgi?id=6045&gid=393&hid=138&oid=138. You can, however, turn it off when you wash, but what if you forget? What if a teenage child forgets?

26-05-2008, 10:12

If you want to take your own life, you can do it without grounding.
no, such a desire did not seem to be recorded among family members... thank God..:)

I have an RCD and a storage heater :)

26-05-2008, 10:17

26-05-2008, 10:31

Can. You just need to call a competent specialist.
RCD - Residual Current Device, turns off when the current starts to “flow” in the wrong place. Saves lives.

As I understand it, it’s possible just with an RCD.

Pronya Pavlova

26-05-2008, 11:26

I am of course conscious from a safety point of view, but... in ships and Khrushchev buildings there is no grounding by definition - so what? No one there has washing machines or hot water heaters? don't tell me my slippers

Pronya Pavlova

26-05-2008, 11:28

Because when they built Khrushchev houses and ships, they didn’t even dream of washing machines (as they are now), dishwashers and boilers...

26-05-2008, 11:33

no, such a desire did not seem to be recorded among family members... thank God..:)
Thanks for the bunch of links, I'll try to get through them.:010:

What is an RCD? some kind of thing that can be placed in ungrounded places?

I am extremely far from electricity and physics. therefore, the questions, apparently, will be stupid... why didn’t these..hmm..builders provide for this grounding then?..and what should I do now? Can the lack of grounding be somehow corrected? or do we now only have to live and be afraid??:001:
Need an electrician. Everything should be done by specialists, IMHO. There is no “ground” in the apartment - there is in the panel on the staircase, there is no panel on the stairs - there is in the basement or on the first floor. Electron damage electric shock in the bathroom... Those who have washed themselves “successfully” will no longer be able to make claims...

26-05-2008, 12:07

Termex's store on Blagodatnaya is called "turnkey", consult there. They work on weekends. Indifference in this matter will not be tolerated. You don’t take wet clothes out of the washing machine while standing barefoot in the bathroom under running water, do you? (Rhetorical question:))) Otherwise, options would also be possible...
T-T-T. God bless all the people who don't care!

26-05-2008, 12:31

26-05-2008, 12:35

I can give you the phone number of a specialist who can connect Thermex and other plumbing fixtures. The master is already very experienced in years. He takes money in moderation.
And me, please... :091:

26-05-2008, 12:42

As I understand it, it’s possible just with an RCD.

I’ve been thinking hard, it turns out that the washing machine and dishwasher (and refrigerator??:009:) also need to be connected through an RCD? does this thing connect to the whole apartment at once? or do you need to connect your own RCD to each device?? :009:
help me put things in order in my head!:091:

A so-called fire protection RCD is installed throughout the entire apartment - it cuts off all power supply in the event of a current leak and possible fire; it does not save a person from electric shock, since the rating is 300 mA (a current of no more than 30 mA is considered safe).
Next - all potentially dangerous consumers (especially those in which “wet” processes occur) water heaters, washing machines, dishwashers, sockets in the bathroom, etc. - they are connected along their lines through an RCD with a nominal value of no more than 30 mA.
Why everyone? So that when a malfunction occurs, it is the culprit who is switched off, and not all consumers en masse, then you won’t be able to find the cause.
The refrigerator is not a particularly dangerous electrical consumer.

Example: the common horse-house episode about killing a person in a filled bathroom by throwing a working hair dryer into it does not work if a working RCD is correctly installed on the outlet line in the bathroom :))

26-05-2008, 22:35

A so-called fire protection RCD is installed throughout the entire apartment - it cuts off all power supply in the event of a current leak and a possible fire; it does not save a person from electric shock

How does this not save?:001: but what does it save?:009:

Many thanks to everyone who responded!:flower:, although the answer to my question - what will replace grounding for us - did not work out... or did I just not understand it?..:009:

Tagiyev, thank you very much for the master, :flower: but we have nothing to connect yet - now. My husband can do a great job on his own - two. He installed all the electricity in my apartment from scratch, and today he assembled the panel and connected the meter. An electrician with a license arrived, checked everything, was surprised at the correctness and sold the work completion certificate for 500 rubles.. :) We just don’t quite understand how to deal with grounding, but otherwise we have full order! :008:

27-05-2008, 09:15

how does this not save?:001: what does it save?:009:

Saves an RCD with a nominal value of no more than 30 mA:ded::))
In a barren building, the so-called “earth” - the PE conductor, is usually pulled into the apartment from the floor board body, this is provided that the floor boards are connected in the riser by a metal connection, and there is still some kind of grounding near the house.

When purchasing and installing numerous electrical equipment, little attention is paid to the issue of its grounding. A situation arises when there is a lot of expensive equipment in the apartment, but none of the devices is grounded. What are the dangers of this state of affairs, and how to ground the water heater? Let's look at these questions in order.

Why does this problem occur?

The housing stock was mainly created in the last century. In many private sector buildings, as well as in multi-apartment buildings, there is basically no grounding. And indeed: what kind of grounding can there be in buildings where stoves and “titans” for heating water are still preserved? In such conditions, most residents try to solve the problem using makeshift (not always correct) methods. And those who doubt whether it is necessary to ground the water heater generally leave electrical appliances without proper connections.

Is it necessary to ground a tankless water heater?

The main role of grounding (the conductor connecting the electric water heater to the ground) is to ensure the safety of residents using the electrical appliance. Protective function designed to prevent people from getting electrocuted when touching metal surfaces that are under voltage. It's strange that this one is quite wide known fact often ignored. Everyone is afraid of exposed wires, and ungrounded objects are considered almost the norm. From the point of view of the safety of users of electrical appliances, the answer to the question of whether the water heater needs to be grounded is affirmative.

Needless to say, if you do not ground the water heater, its service life can be significantly reduced. In most cases, the heater tank is made from of stainless steel. This is an excellent durable material, which, however, is susceptible to the negative effects of stray currents generated in an electric heater without connection to the ground. Currents pass through thin stainless steel and leave micropores in it. Do I need to explain that if the water heater is not grounded, the pores will gradually increase and lead to loss of tightness. Regardless of where the tank is located (in an apartment or in a country house) and how often it is used, its service life will be significantly reduced.

Thus, having learned how to properly and safely ground a water heater, you can get a kind of “lightning rod” for harmful micro-discharges of stray currents generated during the operation of this equipment.

How to ground an instantaneous water heater in an apartment

To the question whether it is necessary to ground a water heater, we answered above. The safety of home occupants is not something to be taken lightly. No less left important point: how to ground a water heater?

Depending on the type of housing or premises, the approach to this process may differ. Grounding in a private house located directly on the ground is not as difficult as in apartment building. How to ground a water heater in an apartment so as not to damage the equipment or disturb the neighbors?

Most common in domestic realities not so long ago there was a way to short-circuit the grounding conductor to any metal object in an apartment that is directly connected to the ground. Few people knew how to properly ground a water heater or other appliances. Were considered ideal water pipes, sewerage and drainage systems, heating or even gas supply.

IN panel houses can be grounded through the embedded parts of the panels, which are connected to the ground through reinforcement inside the concrete. As it turned out, over time, it was the second option that turned out to be more rational, because it made it possible to ground the flow or storage water heater in the apartment without harm to the pipeline systems, since stray currents do not destroy them. Besides, great amount Residents have replaced and continue to replace the iron pipeline within their apartments or entire entrances with plastic ones. As you might guess, pipes made of such material are not suitable for grounding an instantaneous or storage water heater.

Another option for how to ground an instantaneous or storage water heater in an apartment can be called “re-grounding” or “grounding”. Its essence is that the grounding conductor is shorted directly to “minus” electrical circuit. This should be done not in the outlet where the heating tank is connected, but as close as possible to the distribution panel in the entrance or apartment.

How to ground an instantaneous water heater in a country house or in a private house

Residents of the private sector should take no less care of their electrical appliances. Is it necessary to ground a water heater in a country house or cottage? Definitely yes! Boiler in a private house, in the country, garden plot must also be connected to the ground. As a rule, in order to ground a water heater in a private house, conductors and circuits are provided for in the designs, although it happens that they are not. In this case, it should be mounted and a grounding frame should be installed near the switchboard. This looks like a triangular pit with electrodes driven into the tops, to which the grounding conductor coming from the shield is connected. As you can see, you can ground an instantaneous or storage water heater with your own hands if you have some simple tools and materials. Of course, it wouldn’t hurt to turn to professionals so that the work is carried out efficiently and safely.

Before grounding the water heater in the country, it is worth checking that no pipelines or any communications should pass in the area of the frame. It is recommended to make the distances between the pins 0.5–0.7 m. And since it is necessary to ground not only the water heater, but also all electrical appliances in a private house, it is recommended to take the cross-section of the electrodes (profiles, corners or pipes) at least 15 mm.

Thus, you should not even think about whether the water heater needs to be grounded. This is an obvious rule for using devices. It is recommended to carefully consider how to ground a water heater efficiently and safely in the specific conditions of a house, apartment or cottage. And then the equipment will serve you for a long time and without failures.