Warm water is part of the comfort of every home, be it for washing dishes, washing hands or taking a shower. But it doesn't always come out warm from a central system. If you don't have this, the boiler or hot water storage tank has to be fixed. The hot water tank offer is large, but what is the difference between pressureless and pressure-resistant, open and closed hot water tanks?
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| Model | Hot water tank ZANKER Haustechnik, WO 5 US, 5 L, 2 kW | Hot water tank Bosch Thermotechnik Tronic Store Compact | Hot water tank Stiebel Eltron unpressurized small tank | Hot water tank eldom 72326NMP, boiler 15L above table | Hot water tank G2 Energy Systems electric tank, 150 L | Hot water tank Gorenje, 15 L, EEC A, enamelled, upper table | Hot water tank Gorenje, 10 L, EEC A, enamelled, undercounter | Hot water tank Thermoflow SETU UT 5 N undersink, set 5 L | Hot water tank Stiebel Eltron 073112 HFA/EB80Z | Hot water storage tank Stiebel Eltron unpressurized, UFP 5 t, sub-table |
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| Brand | Zanker building technology | Bosch thermal technology | Stiebel Eltron | Eldom | G2 Energy Systems | Gorenje | Gorenje | thermal flow | Stiebel Eltron | Stiebel Eltron |
| Result | The Best Suggestionstest-vergleiche.com1,5Very good! |
Price-value for moneytest-vergleiche.com1,7good |
TOP Productstest-vergleiche.com1,6good |
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TOP Productstest-vergleiche.com2,0good |
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TOP Productstest-vergleiche.com2,2good |
TOP Productstest-vergleiche.com2,3good |
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| Dimensions (H | 41,5 x 25,2 x 21,5 cm | 39 x 22 x 25,8 cm | 42,1 x 26,3 x 23 cm | 52 x 28,5 x 28,8 cm | 52 x 35 x 37 cm | 50 x 35 x 31 cm | 50 x 35 x 26,5 cm | 42 x 27 x 180 cm | 110 x 50,2 x 45 cm | 41,8 x 25,2 x 22,2 cm |
| temperature adjustment | 35 - 85 °C | 40 - 85 °C | 35 - 85 °C | 12 - 80 °C | 15 - 65 °C | 10 - 75 °C | 10 - 75 °C | 35 - 75 °C | 0 - 80 °C | 35 - 85 °C |
| Heating capacity | 2 kW | 1,8 kW | 2 kW | 2 kW | 1,2 kW | 2 kW | 2 kW | 2 kW | 6 kW | 2 kW |
| Hot Water Tank Type | Small tank for a washbasin | Small tank for a washbasin | Small tank for a washbasin | Small tank for a washbasin | Hot water boiler suitable for showers | Small tank for a washbasin | Small tank for a washbasin | Small tank for a washbasin | Hot water boiler suitable for showers | Small tank for a washbasin |
| capacity | 5 l | 5 l | 5 leeks available in 10 l | 15 l | 30 l | 15 l | 10 l | 5 l | 80 l | 5 l |
| Mounting | Under-counter mounting can be hidden in the base cabinet | Under-counter mounting can be hidden in the base cabinet | Under-counter mounting can be hidden in the base cabinet | Wall mounting incl. bracket, visible on the wall | wall mounting incl. Bracket visible on the wall | Wall mounting incl. bracket, visible on the wall | Under-counter mounting can be hidden in the base cabinet | Wall mounting incl. bracket, visible on the wall | wall mounting incl. Bracket visible on the wall | Under-counter mounting can be hidden in the base cabinet |
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Not everyone has a central hot water supply. Their advantage lies in having access to hot water at all times, regardless of whether it is in the basement or the attic. The disadvantage is that it requires complex piping throughout the house. This is not only expensive, but is also more expensive for us than hot water produced on site due to heat losses in the pipe network. However, many customers are put off by terms such as high and low pressure, open and closed construction. The difference isn't all that difficult. With our water heater comparison of Test-Vergleiche.com, we would like to shed light on the darkness and explain the most important differences to you in more detail.
As the name suggests, the electric water heater makes hot water available where it is needed. A mini instantaneous water heater is sufficient for the guest toilet, a 5 l hot water boiler for the hand wash basin and a 10 to 15 liter storage tank is the right choice for the sink. Hot water tanks with a volume of up to 80 liters are ideal for showering. The advantage of the whole thing is that the hot water is produced on site and has no heat loss through long pipe networks. As a rule, all hot water storage tanks are connected via a normal household socket. But hot water tanks are not the same as hot water tanks, there are two major differences, the non-pressurized and pressure-resistant hot water tanks and the best hot water tanks are not always the cheapest. If you order a hot water tank, you must pay attention to the following:
It is also known as an open hot water tank or a low-pressure hot water tank. It is used to supply the washbasin or sink close to where it is needed. He is not under the pressure of the water pipe. The major difference to closed storage systems is the fact that there is only one tap here. This means that special fittings are required for this. You can recognize them by the three connectors. With an open tank, the tank is always connected to the outside air. When hot water is drawn off, the valve opens the flow of cold water to the bottom of the hot water tank. Since the already heated water in it rises, hot water comes out of the tap. This means that the cold water in the inflow pushes the warm water out upwards. Non-pressurized hot water tanks are bestsellers for a single washbasin or sink.
The major difference to the open hot water storage tank is the supply of several tapping points via one hot water storage tank. The shower, bathtub and washbasin can thus be supplied with warm water from a single hot water storage tank. However, the line paths between the individual tapping points should be as close together as possible so that there is no heat loss. In such a reservoir, the line pressure of the water line is usually between 3 and 5 bar. This pushes the heated water to the drainage point. No special low-pressure fittings are required for this, but a safety valve, which compensates for the expansion of the water during heating. Only one pressure-resistant hot water storage tank is favorable for several tapping points.
![Bosch Tronic Store Compact 5 liter electric storage tank - under-table device, ready to plug in, pressureless, 230 V, white-grey [Energy Class A]](https://m.media-amazon.com/images/I/21XZxqAkG1L.jpg)
Starting with the 5 l hot water tanks up to the large 200 l hot water tanks as standing tanks, there is a wide variety of volumes for different applications. You can find out who needs which volume here:
The individual areas of application can also be subdivided according to individual, group or central supply:
In principle, a boiling water hot water boiler is also a hot water storage tank with a heating element. Temperatures from 35°C to boiling water can be produced and stored in the device. When the set temperature is reached, there is a signal tone.
When evaluating the hot water tank, this is one of the most important questions that you need to clarify first. If you only need a hot water boiler for the hand basin or sink, one tap is enough and you have to opt for an open hot water tank. If you want to connect two or more taps to the same hot water tank, it must be a closed system.
Anyone who just wants to quickly rinse a few plates or wash their hands in the guest toilet will definitely get by with a 5l hot water tank. By the time you use the faucet the next time, the water that has been drawn off has already been warmed up again. If you wash all your dishes in the kitchen sink and also need warm water to prepare meals, you can switch to a 10 or 15l hot water tank.
If you want to use a hot water tank for showering or bathing, you need a larger supply of hot water. Here it should not be less than 30 liters, better still 50 or 80 liters.
All small storage tanks with a volume of up to 15 liters can easily be attached below a tap or under the sink. They don't bother you there. However, larger hot water boilers are usually designed for wall mounting.
Most hot water tanks up to a volume of around 50 liters have a connected load of 2 kW and are suitable for connection to a safety socket. Make sure that no other consumers are connected to this socket circuit, this can lead to the cable heating up and, in the worst case, to a fire. Hot water boilers over 50 liters can sometimes also be connected to a fixed 400V connection point.
Hot water tanks produce hot water. The temperature range is usually steplessly selectable. On some models you can preselect a maximum temperature. This prevents, for example, that you burn yourself when opening the tap carelessly.
Most open storage tanks with only one tap have the EEFK "A". They are well insulated and therefore have no heat losses. In the case of closed hot water storage tanks with several tapping points, you tend to find “B” or “C”. This is due to the fact that there is some heat loss, albeit small, via the connected pipes.
In contrast to the closed models, the open water heaters are cheap. This is due to the fact that closed hot water boilers have to withstand all the water pressure and therefore require a particularly strong jacket. Closed water heaters are much more expensive than open ones!
You can buy small storage tanks in an open design and closed storage tanks up to about 50 liters in retail stores. Our hot water tank purchase recommendation: First find out on the Internet which models are available, which manufacturers are behind them and how the individual models differ in a hot water tank price comparison. In the next step, you can order and buy your hot water tank online and don't even have to step outside the door.
Hot water is one of the comforts of life, but not everyone has the option of a central hot water supply. That is why there are hot water storage tanks that can be used for the kitchen, bathroom or shower and without much installation effort. The only difference is whether you can get by with one tap or whether you need two or more. Depending on the situation, a different system must be used.
