How to choose the best water heater

To solve the problem of hot water in an apartment or a private house, in the country you can heat the water using electric water heaters. There are several types of them, and in order to decide which water heater is best for your situation, you need to know their advantages, disadvantages and operating features of each type of equipment for heating water.

Water heaters increase the comfort of life

What are household water heaters and how they differ

First of all, water heaters differ in their principle of operation. They are:

• flow-through type - heat the water passing through the device;
• storage type - the water in the heater tank is heated;
• flow-through storage - have two modes of operation;
• bulk.

It is difficult to say which water heater is better. If we talk about appearance, then the main external difference is size. Accumulative models are large, flowing models are small. But size is not all you need to figure out what's best for you. You need to know the advantages and disadvantages of each type of equipment.

Types of electric heaters for home and summer cottages

Cumulative models

A storage water heater (the second name is a boiler) has a solid size - from 30 to 200 liters. Inside there is a heating element - heating element. It can be one or several. The heating elements can be turned on in parallel (always work simultaneously) or in cascades (turn on as needed). With cascade switching, there are several heating modes - for more rational energy consumption.

Many more models contain a thermometer to conveniently control the water temperature and a thermostat to maintain the set temperature. The desired temperature is set by turning the thermostat knob to a certain position.

The structure of the storage water heater

The storage water heater always contains a certain amount of water. It is heated with the help of electric heaters. They are of two types:

• TEN (Tribbed ElektroHheater). Inexpensive classic solution. They change quickly and easily, and are available in a wide range in any specialty store. The disadvantage is that they heat the water for a long time.
• Spiral heating element. More powerful heaters, which quickly heat large volumes of water, allow you to accurately maintain the required temperature. But they are more expensive (affects the price of the water heater), and their replacement is also more difficult.

Principle of operation

Regardless of the type of installed heater, the operating principle of the storage water heater is the same. When the set temperature is reached, the thermostat turns off the power supply, the heating stops. Further, the temperature is maintained in automatic mode. When the water cools down by 1 degree or cold is added to the tank at a flow rate, heating is turned on. As soon as the set temperature is reached (or rather, one degree higher than the set one), heating stops. This is how storage water heaters with automation work. They are convenient in that they do not overheat (if the automation is working) and you always have hot water available, which is heated the way you wanted. Such equipment usually has two modes of operation - with or without temperature maintenance - in manual mode.

Internal structure of the boiler

Insulation is used to keep the water temperature as long as possible. It is laid between the walls of the tank and the body. With good thermal insulation, even with hot water, the case remains cold, maybe a little warm. It is clear that if the temperature lasts for a long time, the cost of maintaining it is low. Even if you turn off the keep warm function, the water will be hot even after 24 hours.

There are very simple electric water heaters that do not have a thermostat. They are switched on / off by a toggle switch - manually. As you understand, in this case, there is a possibility that the water heater will boil and fail (if you forget to turn it off).

There is one more nuance - the stepwise inclusion of heating elements. Usually two or more of them are installed in the case, and several heating modes are also made. One - more powerful, in which all the heaters are turned on, the rest are softer - one or two heating elements can work, depending on their total number. What is it for? In summer, you can use heating in a gentle mode - the water heats up so quickly, in winter they usually use all the heaters - wait less. In general, you can thus regulate the heating rate of the boiler. We drained all the hot water and the next batch is needed quickly - turned on at full power, there is no such need - you can not overload the networks by turning on half power.

Where you can install a storage water heater read here.

What materials are tanks made of and features of their maintenance

Storage water heater tanks are made of stainless and ordinary steel. Ordinary steel is covered with protective layers of enamel, stainless steel does not need them. From this point of view, it is easy to say which water heater is better - with a stainless steel tank. But it is also more expensive. But the service life of such equipment is much longer - the enamel, even the highest quality, peels off over time.

The storage tank of a stainless steel water heater looks like this

To extend the service life of the enamelled coating, magnesium anodes are installed in storage steel water heaters. They require periodic replacement - during operation they "melt", and their condition is monitored by a special sensor with an indicator displayed on the front panel. The status of the indicator monitors the need to replace the anode.

How to install a boiler (storage water heater) with your own hands, see here.

How to choose and which one is better

In most cases, storage water heaters are installed in private houses or in apartments of multi-storey buildings where there is no centralized hot water supply. Equipment is selected according to the volume of the tank. If you do not like restrictions, you can count on the basis of 50 liters of hot water per family member. That should be enough. In the tank, it heats up to, say, 70 °. Using this is unrealistic, you will dilute it. As a result, there will be 100-150 liters of warm water per person (depending on the temperature of the water in the water supply system). This is without taking into account the fact that during consumption, the water is also heated.

It's easy to get lost from the variety of models

Everything is clear about the material of the tanks: there is a possibility, it is better to take a storage electric water heater with a stainless steel tank. The number of operating modes is not so critical, but it is also a good option, although such models are more expensive due to a more complex scheme.

About which company is better to choose.Nobody can objectively tell you which water heater is better - different needs and demands of people. But you can draw some conclusions from the operating experience. People speak well of the companies' storage heaters:

• Termeks. If we talk about the prices for water heaters with a stainless steel tank, then this company has no competitors at the price. It's hard to say in terms of quality, reviews are different.
• Real. Quite good storage boilers, the main thing is that there are consumables in your city.
• OSO. Very good but expensive.
• Electrolux (AEG). A well-known company with stable quality.

Instantaneous water heaters

The flow-through water heater has more modest dimensions. It is a small box that attaches to the wall. There is also a tank with heating elements inside, but their dimensions are very miniature, and heating elements usually have the form of a spiral - in order to better heat the passing water.

One of the necessary elements is a flow sensor. It monitors the appearance of water movement in the device (the tap is open) and gives a command to turn on the heating element. When the tap is closed, the flow sensor turns off the power supply.

Internal structure of instantaneous water heater

There is also a thermostat that sets the water temperature. It can be of a rotary type with a scale, there are models with an electronic display with push-button or touch control.

Pressure and non-pressure flowing water heaters, their connection

There are two options for instantaneous water heaters - system and individual. System ones cut into the risers of cold and hot water, they are also called pressure pipes. Several points can provide at once - for example, a shower, a sink and a washbasin. There are 220 V system instantaneous water heaters with relatively low power consumption (about 8-9 kW), but they can heat a small amount of water. There are very powerful installations - up to 32 kW, but they are three-phase - 380 V.

Installation of a system (pressure) instantaneous water heater

The pressure flutes have two large classes.

Individual instantaneous water heaters - non-pressure - are connected to cold water. At the outlet they have a flexible hose with a nozzle or, as an option, a tap for washing. These devices are good for the period when the hot water supply is turned off or as a solution to the problem of hot water in the country.

Connection of a pressureless instantaneous water heater

Please note that the stopcock is only on the supply and you can close the hot water only with its help. Connecting shut-off valves at the outlet will sooner or later lead to a rupture of the tank, in which the water is heated. This happens when the automatic water cut-off does not work. And it is not designed to track water consumption, but only monitors its appearance / disappearance at the inlet. So sooner or later a crash happens.

When connecting pressure and non-pressure versions, grounding is mandatory. And in general, it is advisable to pull the power supply to such partitions with a separate line - high power consumption, the combination of water and electricity is an unsafe combination. Normal wiring may not hold up. Therefore, a separate line from switchboard, on which there is a machine and an RCD.

Why you need a safety valve for a water heater read here.

Control type

There are two types of flow-through water heater control:

• Hydraulic. When there is a flow sensor at the inlet (the first photo in the section), at the signal of which the heating element is turned on / off. The disadvantage of such a system is that it always turns on at the same power. Some models have several power modes, but they must be changed forcibly each time (press the buttons).
• Electronic. The work is controlled by a microprocessor, which monitors the state of the device using several sensors. These systems allow you to maintain the required temperature.

Hydraulically controlled flow-through water heaters can only add a certain number of degrees to the water temperature. Which one exactly depends on the power of the heating element, but on average it is about 20-25 ° C.This means that in summer you will get quite warm water at the exit - about + 40 ° C, and in winter it will only be slightly warmer + 20 ° C, since the incoming water is very cold and simply cannot heat the device to higher temperatures.

More powerful models - system ones, with a Sistem attachment - have electronic control and can cope with the task of maintaining the set temperature. Their disadvantage is that they require high power and high cost. But if you have such an opportunity, the automation will maintain a constant (set by you) temperature at any time of the year. The installation rarely works at full power, but still it is required to pull the power supply line at maximum power and use it to calculate the machine and the RCD.

What are the flow heaters made of?

Internal filling can be:

• Made of copper. These models differ in very good characteristics - they quickly heat water. Copper has high thermal conductivity and transfers heat quickly.
• Stainless steel. Not a bad option, durable (if the water is not hard).
• Made of plastic. The cheapest and not the most durable. Although special plastic is used, it is better not to buy such flutes.

The choice of an instantaneous water heater on this basis is obvious. If possible, buy with a copper "filling", but stainless work well.

They pull the power supply with a copper wire with a cross section of at least 3.5 mm (with a power consumption of up to 7 kW) and 4 mm - up to 12 kW. By the value of the consumed current, the machine is selected, the RCD is taken one step higher with a leakage current of 10 mA. With this method of connection and a normally working grounding, there will be no problems.

Selection features

When choosing an instantaneous water heater, you need to focus on several indicators:

• minimum / maximum working pressure;
• power consumption - not so many kilowatts are allocated to a house or apartment, so not everyone can connect a 12-20 kW device;
• the material from which the tank and the heating element are made;
• degree of protection - whether or not it can be mounted in the immediate vicinity of a tap or shower;
• what kind of water it can work with (is it permissible to use it with water of your type - hard, with a high iron content, etc.);
• degree of heating - to what temperature and how much water can be heated in 1 minute.
  

  One way to install

All these parameters should be in the description. Having picked up several models, you can then, according to reviews, or based on technical characteristics, decide which water heater is better. If we talk about firms, the best quality is German and Italian devices. With the Chinese - how lucky, although many firms have moved production to China. And now most of the household appliances have dual "citizenship" - usually written - the birthplace of the brand and the place of production. Most of such equipment works reliably, since firms value their name and introduce strict control over product quality.

Specific models

There are flow-through water heaters of non-standard format. The most common is a tap with a flow-through water heater. This is an interesting option for a summer residence, for example, but it is difficult to say how things are with maintainability - there are not very many users of such devices yet and the operating experience is quite small.

Instantaneous water heater for tap

Which water heater is better: instantaneous or storage

Deciding which water heater to buy - a storage boiler or a water heater - is, in principle, not difficult. First of all, the limiting factor is the power consumption: for storage water heaters it is 3-4 kW, it is pointless to take less than 7-8 kW for instantaneous water heaters - they can provide heating of only a very small volume of water. Not everyone has the ability to install such powerful equipment.

Secondly, you need to watch whether you will constantly use an electric water heater or only periodically. With periodic use, especially in the summer period, instantaneous water heaters are convenient, and moreover of an open type (individual ones, which are installed next to the sink). For example, this is a great way to heat water in summer shower in the country to a comfortable temperature, if the sun did not cope with this task. It is also a way to solve the problem in apartments when the hot water supply is turned off for repairs.

For constant and regular use, storage water heaters are more economical and convenient. Modern models "hold" the temperature for more than a day, so the electricity consumption here will be rather less than more.

Instantaneous storage water heaters

This is a combination of the two previously described devices. They work in two modes. If the water consumption is small, water is supplied from the storage tank, if it increases, instantaneous heating is also connected. The equipment is very convenient but expensive. There are not so many options. This is Stiebel Eltron SHD for 30 liters and 100 liters. Price - $ 1500-1750.

Technical characteristics of instantaneous storage water heater

Bulk water heaters

An excellent solution for giving or in the absence of tap water in the house. A bulk water heater is a container with a lid in which a heating element is mounted. The container can be made of stainless steel, plastic, ordinary enamelled steel. The temperature is regulated by a thermostat. A shower hose is attached to the body.

There are two types of such devices - gravity and pressure generated by a small built-in pump (Alvin EVBO). Self-flowing bulk water heaters must be hung above the head. You can take a shower, then the water flow will be weak. Models with a pump have more pressure, but the capacity of the tank should be decent and this model cannot be called a marching model.

The functions here can be as follows:

• maintaining the set temperature;
• automatic shutdown after heating;
• the presence of an accumulator and a pump to create pressure;
• status indicators.
  

  The device of the bulk water heater

Bulk water heaters are a primordially Russian invention and all manufacturers are Russian. There are similar electric water heaters of the following brands:

• Success;
• Alvin Evbeau;
• Aquarius;
• Elbet;
• Mister Heath Summer resident;
• Story.

The devices operate on a 220 V network, their power is about 1-2 kW, the price is from $ 20 to $ 100 - depending on the functionality and material of the tank. Which is the best water heater in this category? Stainless steel with pressure, but these are just the most expensive models.