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Selection of flow or water heater

Selection of flow or water heater Happened to my friend this history. On the eve of March 8 decided to make his wife a gift. And   selected the instantaneous water heater , to a favorite for a while off the hot water not suffered from the basins and scoop. An electrician, he held a shield from a separate power cord. Because the device is powerful enough – 5 kW. In general, showed an enviable activity. The hour « X », wife proudly retired to the bath, and he, pleased to TV – Watch « stopping power ». And suddenly ... out of the bathroom – a terrible cry. The essence of « messages », omitting some words and expression, was as follows: « The water is cold, if I tap I cover the water to become hot, so weak stream flows, that I'm all in a lather and merznu. You – man, do something » ...

« Man » I ran the service center. And what do you think he was told? It turns out that if the power of flowing water heater – 3.5 kW, is greater than 3 liters per minute of hot water in any case you do not get. And to take a full hot shower, need power of 8 kW and above.

That's the story. What to do? After flowing water heaters successfully selling today, many firms tout their dignity, and they certainly are. Firstly, during a flow-through water heater, no matter how much you keep the tap running, hot water will never end. Unlike the select   storage water heaters , in which the hot water in the tank might end after a while, it is possible (depending on the tank volume), cold water flows. But the instantaneous heater this will not happen ever.

Secondly, compared with storage, instantaneous water heaters make a small size. Since they do not need a reservoir hot water storage.
The main advantage of select   instantaneous water heaters – their small size

Now, about the shortcomings of « protochnikov ». I was told professionals to their disadvantages include a large lump sum consumption power. And another thing: if to running the heater to connect multiple water intake points, simply put, a few taps, hot water temperature will depend on how many points working simultaneously. Let me explain. Suppose your flowing water heater « diluted » on the kitchen faucet and bathroom. So, if you decide to take a shower and your wife – wash the dishes, then you have already domyvatsya cold water.

After visiting several companies that sell water heaters, I realized to get a lot of hot water, using a flow water heater can only be achieved if its output of 8 kW and above. So, this pleasure is available only to those homes where there is three-phase electrical network. Alas, in the homes of old buildings with 16-ampere stoppered cylinder with a capacity greater than 3.5 kW to put it is simply impossible. And in homes with electric stoves and new homes where there are 40 or 32-ampere Counters, setting acceptable « protochnikov » 6 kW.

What to do? Output, it turns out there are. To have hot water in only one year old month, when preventive maintenance is a central water supply, shops offer a wide range of so-called small instantaneous water heaters, working on 220 V power consumption, ranging from 1.5 to 8 kW.

Thus, the small flow-through heaters can be divided into two groups:

Pressure – instantaneous water heaters with no attachments, they are provided only entrance and exit for water. They are placed in the riser and « diluted » the whole apartment. This is very convenient, as in the period off the hot water can be not only to take a shower, but use hot water from any tap in the apartment. Switched on and off a water heater is automatically in response to the flow of water.

Free-flow – Flowing water heaters equipped with own shower head (it comes with the device) and working just as the soul. It is certainly convenient, say, in the country. But in an apartment In my opinion, a bit strange when hanging in the bathroom next to two shower heads – one shower from the usual mixer and a number of sticks « shower » water heater.
Low pressure instantaneous water heater is installed in the riser (left)
Free-flow water heaters equipped with flow shower head (pictured right)

In addition, here, for example, that I was told at one service center.

Cases are different ...

As we have said, the small instantaneous heater ranging from 3 to 6 kW can be used only in the summer. And that's why. Recently, in winter, I came to the service center man. On the complaint that the water heater summer worked perfectly, and now, during the heating network accident, refuses to warm water. Like, you will make ...

His popularity is due in summer temperature of « cold » Water, « incoming » tap was + 15 & deg; C. Its small flow water heater capacity of 3.5 kW (with Dt – 25 & deg ;, giving a 3 l/min) in the summer easy « heats up » its another 25 & deg ;. That is 15 & deg; +25 & Deg; = 40 & deg; C – quite suitable temperature for washing. In winter, colder water at the tap, some degree 5. So: 5 & deg; +25 & Deg; = 30 & deg; C – under such water you certainly freeze. And the device itself has nothing to do with it, he is working in normal mode, it is not broke, just climate we have such.

Here's how I commented on the situation in several companies. It turns out, the small instantaneous water heaters designed to warm Asia and Africa. And there are no such differences between winter and summer temperatures, and the water temperature at the tap is always about + 15 & deg ;. It should be only slightly « dogret ».

Or another case. The client comes across sometimes independent. Without consulting with specialists, buying free-flow water heater. Moreover, it connects it totally unacceptable way. Let me explain. According to the instructions before it include, first you need to open the cold water faucet. But for « simplicity » some craftsmen do so: spun shower nozzle on the water heater, which sold complete with pressureless water heater, but instead put ordinary crane. And, without thinking twice, connect the device to the water system. Simply put, it is now actually performs the role of mixing water heater.

But the fact is that this water heater tank is not designed for such pressure water. As a result, water heater breaks down. How do I vividly sketched this picture of the service center, « it swells and breaks ». Can you imagine! Meanwhile, all the instructions written in detail as to be connected instrument, so you do not have a problem.

Or just too exotic example. It is known that the shower heads for the water heater should be cleaned from time to time. In certain bath as showers were used, small instantaneous water heaters. Over time, the holes clogged shower head pieces lime scale and dirt (the water with us, as we know, not the best). As a result, water heater literally « squeezed » of yourself hot water ... And in the end – ... quite overheated and melted.

The thing is that the shower heads for low flow heaters have a very narrow aperture (compared to conventional souls). And that's why. Small flowing water heater able to heat up to desired temperatures are not very large amounts of water. So that the jet was stronger, in the shower nozzle and provides very small aperture. Of course, these are hammered mikrodyrochki scum or debris much faster.
Model « Eureka » company Ariston – a cross between a flow and DHW cylinder (left)
Installation of small instantaneous water heater still better left to professionals (right)

What do experts recommend a service center?

First. If you notice that the stream of water bubbling from the shower nozzle flow water heater, became weaker, it (the nozzle) should be cleaned. And we advise to do it regularly. Remove, rinse and place for some time in a solution that removes scale.

Second. Buy the water heater only in specialty shops or firms. For example, when I told the « incidents from the life of water heaters » in representation of the company « Stiebel Eltron » (Stiebel Eltron), there were very surprised. The fact that their proprietary devices have a fuse which, when water temperature of greater than 65 & deg; C off device simply automatically. Therefore, it is not something that melt, and even can not overheat.

What to choose?

So, we spoke briefly about what you need to know before you go to the store to select flow-through water heater. Let's sum up.

1. Find out more, three-phase network or additional wiring is required for instantaneous water heater that you liked. And refined in ZhEKe, What do you have electrical equipment in the apartment.
2. Ask for what power is calculated selected flow water heater. In other words, « what » it is enough: just to wash hands and dishes, only to have to take shower or hot water is enough for all these manipulations at the same time.
3. Ask: Who will install the device? Do I need to call a specialist with the firm (and, of course, how much will it cost) or is it easy to do yourself?
4. And, of course, be sure to find out the warranty period and addresses and phone service centers.

In addition, the hurt to ask, do we have in the country of spare parts for your chosen instrument. And if there are not too lazy to specify how much it will cost. It happens that any small but important Circuits arise in a very rather big amount.

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