We are so used to comfort that if there is temporarily no hot water in the house, apartment, country house, or bathhouse, we feel very uneasy and uncomfortable. And the hot water supply, even if it is available, is periodically turned off — sometimes for prevention, sometimes after an accident. In order not to rush around with hot pots and kettles during this period, you can choose an electric boiler and install it. Let’s consider how to choose a water heater for an apartment, private house or cottage.
Types of electric water heaters
Before choosing an electric water heater, let’s understand the types and types, understand their advantages and disadvantages. Then the process will be easier. These are the boilers:
- Flowing Heat the flow of water passing through the heater.
- Cumulative. In fact, it is a tank with water that is heated with the help of a heater. According to the installation method, there are: wall (vertical and horizontal); floor;
- Flow-accumulating. At low consumption, water is supplied from a small storage tank, at high consumption, the heating system is connected.
- Bulk This is a small tank into which water is poured from a bucket, after which the heating is turned on. These are small portable models for summer or even hiking.
As you can see, there are more than enough varieties of electric boilers, there is plenty to choose from. We haven’t gone into details yet. The first stage of selection is to decide on the type of water heater. To do this, let’s briefly consider each of the categories.
Electric instantaneous water heaters
The operation of flow-through electric water heaters is based on the ability of water to heat up quickly. The heating element is a heating element, but it is made in the form of a spiral. They are of two types.
- The heating element is wound on the body of the container with running water (dry heating element). Such models are safer (there is no direct contact of water and electrical parts), but with such a device, the efficiency is lower, since the walls of the tank are heated by the heater, and the water is heated by them.
- The heating element, twisted in a spiral, is in a small hermetic tank (wet heating element). Water flows through the turns of the heating element, carrying heat with it. These heaters are more economical, but also more dangerous (in case of malfunction, you can be under voltage). Therefore, the installation of such equipment is mandatory on a line with a circuit breaker and a protective shutdown device (SPD).
When choosing a flow-through electric heater, usually few people think about its internal device. Usually they pay attention to performance and power consumption. So, the best ratio will be in models with “wet” TEN.
By installation method
Instantaneous electric water heaters are divided into system (pressure) and individual (non-pressure). System ones can simultaneously provide several points of water distribution – showers, washing in the kitchen, etc. They have electronic control that allows you to set the required water heating temperature.
The power of pressure household instantaneous water heaters ranges from 7 to 32 kW. Less powerful ones are connected to a single-phase network (220 V), more powerful ones – from 16 kW – require a three-phase power supply (380 V), which not everyone can provide. During installation, system boilers are cut into the cold and hot water supply system (they are connected to the risers at the entrance to the apartment). This is also their shortcoming. And one more drawback: the high price (the higher the power, the more expensive).
Individual instantaneous water heaters have a relatively small capacity – up to 4-5 kW. They provide water to only one of the water distribution points. But they are easily connected (you can just use a flexible hose from the nearest water outlet) and have a low price.
Types of pressureless instantaneous water heaters
According to their purpose, flow-through electric water heaters are:
- for the kitchen;
- for the shower;
Flow-through water heaters for the kitchen have only a tap (goose) in the body, those intended for the shower have a flexible hose with a watering can. Combined ones have both a goose and a watering can. It is not difficult to choose an electric flow-type water heater based on this feature. It is important to know where you want to install them.
Advantages and disadvantages of instantaneous electric water heaters
We will immediately consider the properties and features of flow-through water electric heaters from all sides. So it is easier to understand the pros and cons of such equipment.
If you have electricity, there is hot water. Any time in any amount. The faucet was opened, we waited for a while until the heating element heated up, and we got hot water. This is a plus. But there are also disadvantages.
- The water must be “let down” until it warms up. At current water prices, this is an unnecessary expense.
- At low temperatures outside, the heater is not always able to heat the required volume to the required temperature. It may be necessary to apply very little pressure so that it can heat the water from the starting 2-7°C. Or take a shower in not quite hot water. Usually, they can raise the water temperature by a maximum of 25-30 °C. If the water temperature is 15 °C or higher at the start, this is more than enough, if it is less than 5 °C it will already be cool.
- There is no electricity – you will not heat the water and there is no supply of hot water. It’s also unpleasant.
- There is a fairly solid drawback, which is often decisive when choosing a water heater. This is the power of the equipment. The higher the power, the more water it can heat. But not all power networks have sufficient power reserves. It may happen that when the unit is turned on due to overload, the light will turn off. Then either the network must be modernized, or another solution will have to be sought.
If we talk about prices, the spread is very large. Pressure models cost a lot of money. Their prices start at $200 (the price for devices from unknown companies). Individual ones, on the contrary, are quite democratic in terms of price — about $40 for a more or less normal boiler for one distribution point.
Features of the choice
To choose an electric flow-type water heater, you should focus, firstly, on power, and secondly, on performance. It is indicated either in liters per minute or in milliliters per second. To compare models, convert the data to the same unit system. Yes, the comparison will be correct.
What should you pay attention to? On the appearance of management. It is available hydraulic (on a relay) and electronic. Electronic is more convenient, but such models cost more. Also pay attention to what the heater tank is made of. It can be copper (the best, but also the most expensive), stainless steel (also not bad), plastic (the cheapest and short-lived).
It may also be important to supply – where the water supply hoses are connected. There are two options – bottom and side (right and left). lower eyeliner is more common, as universal.
Storage water heaters
Water storage heaters are familiar to everyone – they are a large insulated tank with built-in heating elements. According to the method of installation, they are wall and floor. The largest wall-mounted ones have a capacity of 120 liters. And they can be hung on not all walls. But floor models can be larger — from 116 to 300 liters. Since tanks are made mainly in the form of cylinders, orientation in space is also important for wall-mounted models. They can be vertical, horizontal or universal (can work in both positions).
Heating elements in electric boilers can be of two types: heating elements (wet or dry) and spiral heating elements. TENs are more familiar, they are easier to change if necessary. However, spiral heating elements heat water faster, but such equipment costs more.
What is the tank made of?
To choose an electric boiler of storage type, first of all decide on the capacity. The smallest ones are designed to heat only 15 liters, the largest of the wall ones – for 120 liters. In general, there are models for 20, 30, 50, 80, 100 and 120 liters.
Having decided on the capacity, pay attention to the material from which the tank is made. The best option is stainless steel. With normal metal quality and welding quality, it can work for decades. But a stainless steel storage water heater is expensive. Cheap models are made of black steel, and so that it does not rust, a ceramic, polymer or paint coating is applied from the inside. Such models are much cheaper. But from the experience of operation, they quickly begin to flow. At least no model with a normal rating could be found.
Type of management
An electric storage boiler can have mechanical or electronic control. Electronic is more modern, provides more opportunities. For example, there is a limitation of the heating temperature.
But mechanical control is easier to operate and cheaper to repair.
Since the equipment is dangerous (the neighborhood of water and electricity is always dangerous), it is good if there is protection in electric water heaters. It is better to choose an electric storage type water heater with at least minimal protection:
- Protection against overheating. An ordinary thermal relay that turns off the power when the set temperature is exceeded.
- Safety valve. When the pressure increases (usually caused by the high temperature inside), the valve releases some water, preventing the bulb from bursting.
There may still be frost protection. This system is needed if you are looking for a storage water heater for the summer house or bath. In the presence of electricity, the water in the tank will gradually heat up. Usually, the temperature is maintained at +5°C so that the water is guaranteed not to freeze into ice and burst the tank. And so that salt deposits do not accumulate on the heating element, a magnesium anode is introduced into the tank. With him, TENs “live” longer.
These are unique models that can work in two modes. If there is warm water in the tank, the heating is not turned on; as soon as the water has run out, and the flow of water is still going on, the instantaneous water heater is turned on. The idea is great, but the equipment is expensive (two water heaters in one housing), so the choice is still quite small.
The bulk water heater is an improved bucket with boiling water. In fact, it is a regular container (usually made of stainless steel) with built-in heating elements, a water tap and/or with a hose and a shower head. For ease of use, a thermostat (we set the required temperature) and a thermostat (required to maintain the required temperature) are added. This is an excellent option for a cottage, a hike (if a generator is available), and a garage.
The bulk water heater does not need to be connected to the water supply. Simply pour water into the container through the filling hole or after removing the lid, and then turn on the heating. The capacity of the tank is 15, 20, 30 liters. There are also few brands. Prices are more than democratic, which is not surprising for such a device.
Which water heater is better?
To choose an electric water heater, decide how much and how often you need hot water. The situations are different, and the solutions for them are also different. Let’s analyze some of the most typical reasons for buying water heaters.
Seasonal shutdown of hot water
The work of communal enterprises is organized differently in different regions. In some areas, there is a seasonal shut-off of hot water during the summer to check the operation of the system. There may be no hot water supply from several days to a month. The solution for these cases can be as follows:
- If the hot water is turned off for several weeks, the best solution is to install individual instantaneous water heaters. They require minimal costs both in terms of purchase and installation/connection. A water heater with a capacity of 2-3 kW is enough to take a shower with water of a pleasant temperature in the summer, and a less powerful heater can be installed for washing dishes. But the main drawback is that there is no supply of warm water. And more. When choosing, pay attention to the material from which the water heating tank is made. Plastic ones are unsuitable for constant long-term use and quickly fail. Models with copper or stainless tanks cost more, so when buying two pieces (for the bathroom and the kitchen), you should already think about purchasing a pressure (system) water heater.
- System flash drive. The most expensive solution both in terms of purchase and connection. There is water both in the tap and in the shower, it is possible to set the required temperature. It can be turned on in the summer and turned off in the winter. It can also work if the water in the system is not warm enough in winter.
- Storage water heater. A good solution if you have the space to put it. The plus is that there is a certain supply (in the size of a tank) of hot water. Minus — you have to wait until the water heats up or find a model with a temperature maintenance mode.
To choose an electric water heater for the summer season, first decide whether storage or flow is more suitable for you.
There is no hot water at all
If there is no hot water at all, storage water heaters are most often installed. Nowadays, they are made like a thermos – in a layer of thermal insulation, which adds volume to them, but reduces the cost of heating water, since it cools down more slowly. This is the decisive factor — the availability of a supply of warm water. On the other hand, if you only need a couple of liters of warm water, you will have to heat the entire volume, which is also irrational. Another disadvantage is that, usually, each water distribution point has its own boiler. A smaller one for the kitchen, a bigger one for the bathroom. This is again an additional cost.
The second way to make an individual hot water supply is to install a system flow water heater and make hot water distribution from it. A good option if there is no way to install a gas column.
How to choose an electric water heater for a summer cottage or garden plot
If there is a water pipe in the cottage, any of the described options is possible. Only system flow boilers are installed very rarely. In any case, when buying a water heater of any type, pay attention to such a parameter as the minimum working pressure. In cottages, the pressure is not high – about 2 Atm, or even 1 Atm or even less. So, the lower limit is very important in this case.
If the water is from a well in the country, even with a pump, but without a system that provides constant pressure, there is only one option – a bulk electric water heater. This is a good replacement for a bucket with a kettle. It is much more convenient to use.