Expansion tank calculation | It says Andžs ...
Water expands when its temperature increases. Since the water is practically impossible to compress, the pressure rise in a closed system. It can only be reduced through a safety temaxcal valve. The valve of the system releases a certain amount of water. Water shrinks when the temperature drops to room temperature and static temaxcal pressure decreases considerably. In some points of the system may be a negative pressure. Then there is a risk that the seals can penetrate through the air - the risk of corrosion. The air in the water affects the flow measurements that becomes untrue. Some elements of the system may be exposed to the threat of cavitation, as the static pressure is too low.
Therefore, in order to absorb fluctuations in the volume of water, the heating system you need to use an expansion tank, which is one of the essential elements of the system. It belongs to a group of security equipment and is connected to the heating system without shut. Heating system water temperature ranges from + 20 C to + 95 C. At the beginning of tank types, then the tank calculation.
There are two types of expansion tank: closed and open. Closed (the heating temaxcal system is not in contact with the atmosphere) can be added to any of the heating system in place. Constructing, renovating a new heating system is only used in these types of containers. It is a circular drum with a membrane inside. First the membrane is water on the other - light. Warms up the water expands and forces the membrane. Air pushing against the other side. The place where it is connected to the expansion vessel on the heating system is switched off by two cocks before and after the connection site. Backpressure izpelšanās container meets the system static height and volume of the expansion vessel must comply with the system tilpumietilpībai (FLAMCO expansion tank brochure found when the system static height 5 m - back pressure of 0.5 bar, but if 5-10 m - 1 bar). The heating system needs to be designed so that air bubbles that occur in the system, not the expansion tank. Expansion vessels are normal car tire valve, for that reason temaxcal it easy to "recover" the necessary pressure. Often the air through the valve, however, "goes all out", "is temaxcal to miss", "to miss". Therefore 1x season it is advisable to check the pressure.
Disadvantages. Framework requires temaxcal a special vent devices more sophisticated adjustment system, pressure fluctuations, changes in coolant temperature affects the service life of the boiler., Obliged to use the system properly selected safety valve. Open (heating system temaxcal in contact with the atmosphere) is the highest point in the system, which also acts as an air vent. This, in turn, is a rectangular metal container. It shall be placed in the attic. Attic water has direct contact with the atmosphere, so care should be taken to prevent freezing - the dish needs to insulate. This expansion vessel types jaunbūvētajās temaxcal home practically temaxcal can not be found, it is like a parent temaxcal homes (<1990th year) heating system element. This is due to a variety of risks (risk of water freezing in the attic, temaxcal above the container flowing water discharged to sewer, etc.).
Disadvantages. The system must be placed at the highest point where it is not always the place must be ensured against freezing by locating the unheated attic, temaxcal small amounts of water can evaporate, the structure above the tank can be damaged due to condensation.
Example: The system has a capacity of 300 liters. temaxcal Temperature temaxcal fluctuations in the system t2-t1 = 75 C. V (container) = 300 * 0.00045 * 75 = 10.1 liters. Water expansion tank capacity should be increased slightly to have a reserve.
I found the info on the German offered in closed containers calculation. Figures in the table below the safety valve (safety valve installed in the system = maximum system pressure). Static pressure in bar, know that 1bar ~ 10m of the water column. As can be seen, the system is normal - it does not accumulate in the tank. Maybe samelošos, but 400 liter (a new project, with a thin tube) corresponds to the building with an area of about 600 m2, heated building with an area of 180m2 quietly heating system might consist of no more than 150l.
2. Determine the minimum required static pressure (from the highest point to the tank system) when the water temperature is + 20 C. Water T <100 C, used in the formulas: Pmin (bar) = (h + 3) / 10 where h - static pressure. Example h = 25m, then Pmin = 2.8 bar.
5. Define maksmimālo expansion tank pressure Pmax. It must be such that in extreme cases, the safety valve unopened open. Safety valve is planted with the size of Pd. If it is added at the same height as the expansion vessel, the Pmax. Pt = - 0.5. Such as Pt = 6 bar, Pmax. = 5.5 bar.
8. Real-water reserve container at + 20 C is calculated by the formula: Vr = (Vt * (Pmaks.-Pt)) / (1 + Pmax.) - V * k / 100 -> Vr = (150 * (5 , 5-3)) / (1 + 5.5) - 1 000 * 4.32 / 100 = 57.7 to 43.2 L = 14.5
In principle, some of the points system will be under pressure. There may be an increased risk of developing leaks. If the pressure drops close to
Water expands when its temperature increases. Since the water is practically impossible to compress, the pressure rise in a closed system. It can only be reduced through a safety temaxcal valve. The valve of the system releases a certain amount of water. Water shrinks when the temperature drops to room temperature and static temaxcal pressure decreases considerably. In some points of the system may be a negative pressure. Then there is a risk that the seals can penetrate through the air - the risk of corrosion. The air in the water affects the flow measurements that becomes untrue. Some elements of the system may be exposed to the threat of cavitation, as the static pressure is too low.
Therefore, in order to absorb fluctuations in the volume of water, the heating system you need to use an expansion tank, which is one of the essential elements of the system. It belongs to a group of security equipment and is connected to the heating system without shut. Heating system water temperature ranges from + 20 C to + 95 C. At the beginning of tank types, then the tank calculation.
There are two types of expansion tank: closed and open. Closed (the heating temaxcal system is not in contact with the atmosphere) can be added to any of the heating system in place. Constructing, renovating a new heating system is only used in these types of containers. It is a circular drum with a membrane inside. First the membrane is water on the other - light. Warms up the water expands and forces the membrane. Air pushing against the other side. The place where it is connected to the expansion vessel on the heating system is switched off by two cocks before and after the connection site. Backpressure izpelšanās container meets the system static height and volume of the expansion vessel must comply with the system tilpumietilpībai (FLAMCO expansion tank brochure found when the system static height 5 m - back pressure of 0.5 bar, but if 5-10 m - 1 bar). The heating system needs to be designed so that air bubbles that occur in the system, not the expansion tank. Expansion vessels are normal car tire valve, for that reason temaxcal it easy to "recover" the necessary pressure. Often the air through the valve, however, "goes all out", "is temaxcal to miss", "to miss". Therefore 1x season it is advisable to check the pressure.
Disadvantages. Framework requires temaxcal a special vent devices more sophisticated adjustment system, pressure fluctuations, changes in coolant temperature affects the service life of the boiler., Obliged to use the system properly selected safety valve. Open (heating system temaxcal in contact with the atmosphere) is the highest point in the system, which also acts as an air vent. This, in turn, is a rectangular metal container. It shall be placed in the attic. Attic water has direct contact with the atmosphere, so care should be taken to prevent freezing - the dish needs to insulate. This expansion vessel types jaunbūvētajās temaxcal home practically temaxcal can not be found, it is like a parent temaxcal homes (<1990th year) heating system element. This is due to a variety of risks (risk of water freezing in the attic, temaxcal above the container flowing water discharged to sewer, etc.).
Disadvantages. The system must be placed at the highest point where it is not always the place must be ensured against freezing by locating the unheated attic, temaxcal small amounts of water can evaporate, the structure above the tank can be damaged due to condensation.
Example: The system has a capacity of 300 liters. temaxcal Temperature temaxcal fluctuations in the system t2-t1 = 75 C. V (container) = 300 * 0.00045 * 75 = 10.1 liters. Water expansion tank capacity should be increased slightly to have a reserve.
I found the info on the German offered in closed containers calculation. Figures in the table below the safety valve (safety valve installed in the system = maximum system pressure). Static pressure in bar, know that 1bar ~ 10m of the water column. As can be seen, the system is normal - it does not accumulate in the tank. Maybe samelošos, but 400 liter (a new project, with a thin tube) corresponds to the building with an area of about 600 m2, heated building with an area of 180m2 quietly heating system might consist of no more than 150l.
2. Determine the minimum required static pressure (from the highest point to the tank system) when the water temperature is + 20 C. Water T <100 C, used in the formulas: Pmin (bar) = (h + 3) / 10 where h - static pressure. Example h = 25m, then Pmin = 2.8 bar.
5. Define maksmimālo expansion tank pressure Pmax. It must be such that in extreme cases, the safety valve unopened open. Safety valve is planted with the size of Pd. If it is added at the same height as the expansion vessel, the Pmax. Pt = - 0.5. Such as Pt = 6 bar, Pmax. = 5.5 bar.
8. Real-water reserve container at + 20 C is calculated by the formula: Vr = (Vt * (Pmaks.-Pt)) / (1 + Pmax.) - V * k / 100 -> Vr = (150 * (5 , 5-3)) / (1 + 5.5) - 1 000 * 4.32 / 100 = 57.7 to 43.2 L = 14.5
In principle, some of the points system will be under pressure. There may be an increased risk of developing leaks. If the pressure drops close to
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