Thank you for your interest in DZ Dražice water heaters, which excel in long service life, trouble-free operation and a number of innovative design and technical solutions in heating and insulation.
Families with small children or no children should take into account the life of our heaters and capacity the volume for future use. When considering combined heating, always choose the larger variant.
For electric heating using the “night tariff”, we recommend heaters with higher capacities.
Number of persons | Recommended capacity | |
Daily tariff | Night tariff | |
1 | 20 l | 50 l |
2 | 20 l | 50 l |
3 | 50 l | 80 l |
4 | 80 l | 125 l |
5 | 100 l | 160 l |
6 | 125 l | 180 l |
7 and more | project |
For electric heating using the “night tariff”, we recommend heaters with higher capacities.
Number of persons | Recommended capacity | |
Daily tariff | Night tariff | |
1 | 100 l | 160 l |
2 | 125 l | 200 l |
3 | 160 l | 200 l |
4 | 180 l | 250 l |
5 | 250 l | 300 l |
6 | 300 l | 500 l |
7 a více | project |
Number of persons | Recommended capacity |
1 | 80 l |
2 | 100 l |
3 | 100 l |
4 | 125 l |
5 | 160 l |
6 | 200 l |
7 and more | project |
Horizontal water heaters are used mostly in constrained spaces.
In general, vertically installed heaters are more functionally beneficial due to the fact that they do not mix hot and cold water as much as horizontal heaters, in which the area of contact between hot and cold water is larger. Only for horizontal heaters with a heat exchanger, the horizontal design has the advantage that the water heated to the maximum temperature is available almost immediately as the exchanger heats up from the top of the vessel.
The total electric heating time is the same for both types. When using an exchanger, horizontal heaters are faster – approximately by one quarter. However, the combined OKC X/1m2 heater is approximately as fast (with the same flow of hot water).
In horizontal combined heaters it is very important for the exchanger to act as a counterflow (is more powerful than co-current). Of course, if the heating water flow direction is not followed, the entire volume can also be heated, but it takes much longer. The heater then has trouble heating up completely and “gravity” does not work.
Circulation means installing a dual hot water distribution and a circulation pump. One water conduit leads to the discharge points, then the other branch leads back to the circulation hole of the heater. A circulation pump is also installed into the system. The distance where circulation could be considered is approximately 6 meters. This length corresponds to an inner pipe diameter of 3". It is not recommended to install a circulation system for small heaters and when heating only at night. The water in the tank gets colder.
One of the most important innovations in the product range is the introduction of the so-called Antilegionella function in OKHE SMART heaters. The function removes Legionella bacteria, which very often occurs in systems with hot water.
Bacteria of Legionella multiply very rapidly in water at 20 °C to 45 °C, but do not survive temperatures above 70 °C. The occurrence of these bacteria can also be promoted by insufficient circulation of hot water in the distribution system and by deposits in heat pipes, water heaters or air conditioners. That is why we have begun to implement the Antilegionella function in the OKHE SMART intelligent water heaters, which destroys the bacteria in a very simple way. The elimination of the bacteria occurs in all modes of the boiler thanks to the planned heating of water to 70 °C, which first start 28 days after putting the heater into operation. This heating occurs only once and cyclically repeats once a month, which is enough to eliminate the bacteria inside the boiler.
A Czech household consumes about 25 % of its total energy demand for making the hot utility water. This is why the sensitive approaches to the warm water and its handling can result in substantial energy and the water savings.
To achieve some of them it is sometimes enough only to set correctly the water heater temperature. The 60 °C setting is deemed optimal.
The distance from the tapping point to the water heater is also important, as the thermal losses are growing substantially at 2 m or more. If there is no other choice, make sure that the pipes have a good insulation („the more the better“ – it applies twice here).
As cutting the water temperature setting times, the economy of the lever-operated mixer taps is 40 % better that that of the normal types (given the water heating power consumption), regardless of the saving on water itself.
These savings can reach even higher with the thermostatic sets used. Here, you will merely set the required water temperature, and the device will do the work automatically, mixing the hot water with the cold. In comparison with the lever-operated sets, these will save up to 50 % of water.
The so-called „fizzers“ will also help us save water as you will not need so much of it when it is mixed with air.
When showering, you will consume about 3-times less water than upon having a bath in a tub.
A tub is certainly more economical for those who prefer the relaxing candlelight baths as the water consumption is less than upon showering over the prolong periods of time.
You can further save additional 30 % of warm water with an economical shower head and its stop valve.
To have an effective schedule making sure that the washing machine is ever full is the right-hand rule for the laundry washing savings. To turn on a half-full washing machine, it would be an evidence of your competitive nature as you probably want to the higher expenses than your neighbor.
In general, the units with the front door will consume 3-times less water and power than those with the top door, but otherwise similar performances. But they buy-in costs, of course, tend to be higher.
The washing water temperature is critical in respect of the power consumption. By reducing the washing temperature from 90 °C to 60 °C, you will save 25 % of power. And there is moreover much laundry that can be washed in cold water.
Concerning the toilets, the substantial water savings can be achieved with combi-bowl using the 6/3 dual flushing system. Unlike the old simple one, with this system you can save up to 8 liters per a flush. Given a four-member family, the water savings represent up to 24,000 liters a year.
When throwing napkins, cigarette buts, and other refuse into the toilet bowl and flushing them, you will hardly win any of the ecological conduct prizes. Next to the future problems with your waste water system, it is useless water wastage. It is much better to buy a small litter basket.
Any untight flush cistern, passing the water down, is very uneconomical as it can waste up to 16,000 liters of water per year. And, in fact, you need not be aware of it at all. If you want to check it, you have merely to put a few drops of the food coloring into the cistern and wait if the tint appears at the bowl bottom.
It is very important to see to it that the taps are tight. 160 liters of water will escape in a month through a single tap, which is just “a little” leaky (10 drops per minute). Should the warm water be the case, the escape also represents a power loss equal to 11 kWh.
The above-mentioned fizzers can also help reduce the water consumption, provided a correct type is selected. In a bathroom the fizzer with the flow rate of 2–3 liter per minute can be enough. But in the kitchen, you will need the flow rate from 6 to 12 liter a minute, of you are filling the dishpan on a regular basis. If, on the other hand, you are used to do the dishwashing under the running water, it is better to use the fizzer with the flow rate of 2–3 liter per minute.
If possible, do not let the warm water on permanently, when washing your hands, brushing your teeth, or while shaving.
Needless to say that the food de-freezing under the running water will certainly increase you final sum for the power and water; it is surely better to use a fridge to meet the purpose.
When washing your dishes under running water, you will consume thrice as much of it than in a closed dishpan.
In comparison with dishwashing under the running water, an economical dishwasher will save some 60 % water and about the same amount of power. Here, the economical conduct secret is the same as with the washing machines – never turn on your dishwasher when it is not full.
In general, the dishwashers able to take multiple sets of dishes are more effective.