Many of us have repeatedly faced the problem of emergency shutdown of hot water. Agree, it’s rather inconvenient to heat the water in a pan in order to wash the dishes or take a dip. And if the family is large, then this can become a real problem.
But there is a solution - these are instantaneous water heaters. They help to increase the comfort level in urban apartments and provide country houses with hot water all year round. Let's figure out how to install a flow-through water heater with your own hands, which any home master can handle.
We will talk about the principles of operation of the heater and about what factors should be considered when choosing it. Consider the features of connecting electrical and gas equipment. Here you will find video installation instructions that will help you better understand the installation.
The principle of flowing water heating
If you are going to independently install water heating equipment, you must definitely get acquainted with its device and the principle of operation.
Heating water in a flow-through device is quite simple: cold water from the water supply passes through the heating elements and at the outlet has a temperature several times higher than the initial value.
For example, water with a temperature of + 10 ° C is heated to a temperature comfortable for taking a shower - + 36-40 ° C. The parameters are adjusted using the control buttons located on the front side of the case.
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The main advantage of instantaneous water heaters is their compact size, justified by the fact that the device is not designed to accumulate hot water
Flowing heaters are produced in a wide assortment, allowing you to equip both several draw-off points and one separate tap
By type of supply, instantaneous water heaters are divided into gas and electric. Gas is more economical, but more dangerous in operation when ill-treated
Electric varieties are easier to install, safer to operate, but the cost of power is significantly higher than paying for gas supplies
The electric type is connected only to the water supply and to the mains. To connect the gas equipment, you need a water supply system, a gas main, a chimney and an electric network if its design includes volatile ignition devices and automation
Both types of water heaters can serve as both the main and additional type of equipment providing the object with hot water
The scope of electric water heaters is generally unlimited. Gas can be installed in houses up to 5 floors not connected to a central hot water supply
To power the electrical equipment, a connection to the central network is required. An alternative is an electric generator. The gas device can be fed with main gas, connected to a cylinder or gas tank
Compact equipment
Flowing appliance for a kitchen sink
Geyser Operation
Electric water heater
Use paired with cumulative type
Scope of use of water heaters
Water heating starts automatically, from the moment the tap is opened. Despite the miniature size of the device, it is able to provide heating to a temperature of + 50-65º C, sufficient to wash the dishes or take a hot shower.
In order for the equipment to work properly, during installation, the following nuances must be taken into account:
- the strength of the wall on which the device is mounted;
- the necessary pressure in the water supply;
- suitability of the electrical network.
If all conditions are met, the quality of the water heater will depend only on your skills.
The standard diagram of the flow type heater device. Heating elements are used in heating models in overall models, and copper spirals in compact ones. A detailed diagram is presented in the product datasheet.
Factors for choosing a water heater
If you have already decided that a instantaneous water heater suits you completely, you need to decide on the right model.
To do this, try to clarify the desired characteristics of the device, that is, analyze the following information:
- number of permanent residents;
- maximum volume of water flow with the simultaneous inclusion of all points of tapping;
- the total number of all water points;
- desired maximum heating temperature;
Data collection will help calculate the capacity of the equipment. In this case, it is better to rely on information provided by the manufacturer. If gas is supplied to the cottage, then you should think about connecting a gas column, and if you are constantly living in a house, then a gas boiler.
Schedule for calculating temperature increase data for an AEG RMC instantaneous water heater at a temperature of tap water + 10 ºС and a voltage of 220 V
In residential buildings with a storey of over five, the installation of gas equipment is strictly prohibited. In this case, the choice is predetermined - you need to buy an electric water heater. He will “save” during seasonal shutdowns of hot water.
Owners of private houses that do not have the ability to connect to systems with main gas will have to give preference to electrical options for equipment that treats sanitary water. This is the case if it is not planned to use bottled gas or install a gas holder.
For self-installation, the degree of installation complexity, the cost of the device, initial equipment, the ability to quickly repair and the availability of spare parts, warranty service conditions and the warranty period are also important.
If the seller offers installation services, consider this option, especially when buying an electric pressure model or gas column.
In addition, another article, which we recommend reading, will familiarize you with the arguments for choosing a instantaneous water heater.
Reasons for self-installation
Do-it-yourself installation of a device that is directly connected to the water supply system and the electrical network is a responsible and serious matter, so it is better for inexperienced users to trust professionals.
However, there are several reasons that allow self-installation:
- cash deficit for payment of services;
- the need for urgent installation of the device;
- a desire for training and the acquisition of new skills (preferably under the supervision of a specialist);
- prospect of repair or replacement.
Of course, if you yourself will understand the device of the water heater, study the instructions and install it, in the future, repair or replacement of worn parts will become commonplace.
In addition, there are special life circumstances that force you to learn to do everything with your own hands. For example, living on a remote farm, from which the nearest service center is more than 300 km.
Electrical Model Installation Instructions
So, we’ll try to figure out how to properly install a flow-through water heater with your own hands, so that it works much longer than the period specified in the warranty card. But remember that the general recommendations must be supplemented by the guidance set out in the technical documentation.
Step 1. Preparatory work - mains check
Not every electrical network can withstand the power of your chosen model. On the market are water heaters with an average power of 3 kW to 27 kW. Old wiring is enough for weak devices to work, but only a new network and connection through an RCD can provide a powerful pressure head heater.
Technical data table that facilitates the diagnosis of the mains and the choice of wire cross-section. When laying new wiring, the manufacturer recommends that local regulations and standards be considered.
Thus, to connect most of the flow-type water heaters, a stationary installation method, an alternating current mains with a voltage of 220 V, a three-core copper cable with a minimum cross section of 3 mm X 2.5 mm, automatic protection of 30 A. will be required.
Do not forget about the required grounding. If the appliance is fixed to a heating wall, the cable cross-section should be increased.
Step # 2. Choosing a place to install
The installation location depends on the type of equipment. A non-pressure type water heater is usually mounted near the point of water consumption, that is, above the sink, under the sink or on the side of the tap. If the non-pressure model, in addition to the gantry crane, is equipped with a hose with a shower nozzle, you should consider the mounting location for it.
Installation diagram of a flowing water heater near a sink / bathtub or shower. The main condition for installation is the availability of the control unit
Labeled Models IP 24 and IP 25 initially protected from direct ingress of water, however, it is better to place them where there is no threat of water from the shower - under the sink.
At the same time, they should be available for switching on (mechanical), adjusting the pressure and temperature - which means that they should be located near the shower or sink. Therefore, installing a instantaneous water heater in a toilet is a bad idea, in a bathroom it is a good idea.
The choice of pressure device dictates other conditions. Usually it is installed near the point of drawdown, which has a maximum load, or near the riser. A powerful water heater is able to provide hot water to the kitchen, bathroom, shower, so the place is chosen based on the feasibility and ease of maintenance.
Installation diagram of a flow-through pressurized water heater: while hot water is in the water supply, taps 3 and 4 are in the closed position, when the hot water is turned off, taps 3 and 4 must be opened, and tap 1 closed
Such devices do not need constant adjustment - they are programmed.
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Protecting equipment from water
Heater in a makeshift shower room
Mount separately from the main mixer
Water heater complete with gander
Step # 3. Wall Mounting Procedure
Wall mounting consists in drilling holes and hanging the device using special hinges or brackets included in the kit.
Two main conditions for proper installation:
- strength of the wall (ideally fit brick, concrete, wood, conditionally - drywall);
- ideal horizontal position relative to the planes.
If the equipment is tilted, there will be a risk of air congestion, and in the future - breakdown. The fact is that the heating elements during operation must be completely covered with water. Due to the skew of the device, part of the spiral or heater may dry out, and the mechanism will fail due to overheating.
Schemes that help to properly fix the water heater on the wall. Pay attention to the dimensions of the fasteners (dowels, screws or screws) and to the features of the wiring diagram
As you already understood, installation requires a drill and certain drills - for concrete or wood.
The procedure is as follows:
- Set the water heater switch to the off position.
- Take the mounting plate (should be included), attach to the wall and mark the location of the holes.
- Drill holes.
- Insert the dowels and screw in the screws.
- Open the housing cover, make holes for water supply.
The next step should be carried out, taking safety measures, since you have to work with electricity.
Step # 4. Electrical connection
Make sure that there is no voltage in the network, and insert the power cable through a special hole in the back wall, covered with a rubber plug. Hang the device on the already prepared screws, check for horizontal deviations.
Strip the ends of the wires in the standard way and insert the three wires into the terminal box. Tighten the fixing screws so that each wire is firmly fixed. Make no mistake in the color coding of wires.
Do not forget that the proximity of electricity and water is one of the most dangerous for human life, so clearly follow the installation diagram from the manufacturer's instructions
It is forbidden to install if there is no grounding and an automatic residual current device (RCD). If there is a leak or a malfunction in the system, the machine will immediately respond and break the electrical circuit.
The UZO installation location is a distribution panel, which is located on the floor or in the utility room, if it is a private house.
Step # 5. Water Connection Options
Usually there are several connection options. For example, the same model can be installed above the water supply node of the water supply (upper connection) and below, under the sink (lower connection), connect the device to closed or open pipes. There are two holes in the device case for piping pipes - hoses with hot and cold water are inserted into them.
Connection schemes: 1 - to hidden pipes; 2 - to open pipes. In the first diagram, you must first set the corners (B), then attach the hoses with gaskets (A). In the second diagram, install the holders (A) on the pipes, connect them with hoses with gaskets (B)
Low-power electric water heaters oriented to a single point of water consumption usually have a hose with a shower nozzle instead of hot water reaching the common line.
For single-point models, there are special installation instructions: the first figure shows the correct installation, the second shows the wrong one. It is strictly forbidden to install a valve at the water outlet!
The water heater can be connected both to the pipes of the central line and to the storage tank, which is 4 m (at least) above the installation site of the device. When supplying water from the tank, constant monitoring of the water level will be required.
A direct connection to a well or a well (in country houses) is also practiced, but only through a rough filter, otherwise the manufacturer will void the warranty.
How to install a gas water heater?
The installation of a gas column differs from the installation of electrical equipment in a large number of requirements and a more complex connection process. However, time and effort is offset by savings in fuel costs — cheaper than natural gas than electricity.
Step 1. Harmonization and compliance
To install a geyser, it will be necessary to bring gas to the house (in some regions - the most expensive cost item), then draw up a competent engineering project and coordinate it in certain instances. Designing a project should be done by a licensed organization.
The procedure for connecting a private house to the main gas supply system is described in detail here. We recommend that you familiarize yourself with the information provided.
To imagine what the requirements are for the installation, you can look at the documents of title:
- General provisions for the design and construction of gas distribution systems of metal and polyethylene pipes (SP 42-101-2003).
- Gas distribution systems (SNiP 42-01-2002).
The basic rules for installing gas equipment include the volume of the room - at least 7.5 m³ and the height of the ceilings - at least 2 m. A prerequisite is well-established ventilation. The minimum diameter of the chimney is 110 - 130 mm (depending on the requirements of the manufacturer).
Minimum distance diagram for installation in the kitchen. As a sample - a gas instantaneous water heater Therm 6000 O of the famous German manufacturer Bosch
Everyone who wants to install a gas water heater with their own hands should understand that the device without installation by representatives of a licensed organization (authorized service center) is completely removed from the warranty and free maintenance.
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Place for installation of the gas unit
Suitable room for installation
Wall Posting Rules
Kitchen sink distance
Distance from gas stove to equipment
Gas pipe faucet in front of the column
Distance between column and mixer
Gas equipment maintenance
Step # 2. Rules for dismantling the old gas boiler
The process of replacing the gas column is faster than installing a new water heater, since no chimney equipment or connection to the gas main is required.
Progress is as follows:
- Close the tap on the gas inlet pipe to shut off the gas supply.
- Unscrew the nut fixing the flexible hose, carefully remove it. If the column is connected in the old way of connection through a metal pipe, you will have to saw it with a hacksaw for metal.
- It is better to discard the old connecting fittings by purchasing a modern, durable hose.
- Disconnect the water supply system - for reliability it is better to turn off the taps at the riser.
- Remove the exhaust pipe, carefully remove it from the chimney.
- Carefully remove the device housing from the wall bracket.
In the process of dismantling, try not to damage the supply pipes, otherwise the replacement of the water heating device will result in the replacement of all adjacent equipment.
Modern geysers (instantaneous water heaters) have a mandatory triple connection: to the gas pipe, to two pipes with water (cold - inlet, hot - outlet), to the chimney
If you notice wear on the pipes, it is better to replace them with new ones - most likely, more reliable models have appeared in stores during the operation of the old device.
Step # 3. Installation Instructions for the new gas model
First, check the chimney. Check the tightness of the joints, the vertical arrangement of the pipe for the removal of gases, the quality of thermal insulation. Do not forget that the outlet must be above the highest point of the roof and be protected from rain by a visor.
Which pipe you will use - flexible or rigid - does not matter, rather, its characteristics depend on the installation conditions. Then check if the ventilation is faulty.
One of the standard options for connecting a gas column, designed to provide two points of hot water with hot water - in the kitchen and in the bathroom (+)
Correct the mounting locations for the new model. Remove the handle of the switch (power regulator), unscrew the fasteners holding the casing, and remove the front of the case. Use mounting loops, screws and wall plugs to hang the column on the wall. Remember: the case should hang freely on the wall, and not stand on the water or gas inlets.
Using flexible hoses, connect the device to a cold water pipe, then connect the outlet to a hot water tap.
Water connection diagram. To mark the connection points for cold and hot water (A and B), they are marked in blue and red. To control inlet pressure differences, the manufacturer recommends installing a check valve.
The next step is to connect the gas. Use a flexible hose to connect the gas valve to the inlet to the water heater. Verification can be done in the traditional way, soaping the junction and opening the gas supply. Lack of bubbles indicates proper connection.
Lastly, a chimney pipe is installed. Most often this is a flexible corrugation, selected according to the diameter of the outlet. Fix one end of the corrugation at the outlet of the column, insert the other into the chimney. Replace the front panel with the switches, tighten the fasteners and test the device.
Operation and Maintenance Rules
Malfunctions can appear both in a few years, and in a month. The risk of breakdown is especially great in case of violations in the operation of the device.
In order for the electrical equipment to work properly, it is necessary to monitor the cleanliness of the filter and clean the aerator from time to time. Perform maintenance work approximately once a year: turn off the water heater, remove any accumulated dirt, and blow out the pipes. Tighten the mounts if necessary.
At geysers, keep the heat exchanger clean, change gaskets, clean the burner and ignition nozzle, and change the water filters.
If maintenance and the simplest repair of a low-power electrical appliance can be done on its own, then it is better to entrust the control of the gas service with which a contract is concluded to control the operation of a gas water heater.
Especially not worth the risk if there is a problem of insufficient pressure of water, clogged water fittings or the heat exchanger is covered with limescale.
Three informative videos will introduce you to the secrets of installing instantaneous water heaters and prevent issues that often arise during the installation process.
Video # 1. Installation instructions for electric water heater Stiebel Eltron DHC:
Video # 2. How to install a CLAGE DSX instantaneous water heater with remote control:
Video # 3. Professional installation of a geyser:
As you can see, you can install a flowing electric or gas water heater yourself, using the manufacturer's instructions or useful videos. However, maintaining the warranty and increasing the life of the device is only possible with the help of professional service.
Have questions while familiarizing yourself with the information we have proposed? Is there any useful information that you would like to share with visitors to the site, or a photo on which you recorded the steps of your own installation? Please write comments in the block below, here you can leave files with pictures.