Water heaters are not considered complex instruments, if the home is inexpensive, costing without having to call the master. Self-repairing water heaters Thermex, armed with basic knowledge about the structure of the unit.
Apparatus heaters Thermex
Water heaters, Termex including electric kettles resemble: set inside the heating element, thermostat-controlled. In teapot, these components are separated, in the water heater installed nearby.
As a heater used heating element - a tubular electric heater. Its design:
- fechral wire or other alloy with high resistance;
- filler-dielectric insulating current-carrying part of the outer shell;
- the outer shell is made of copper pipe.
Copper metal is galvanic couple provoking the electrochemical corrosion, i.e., in a solution of one component is destroyed. Near the metals are copper donors. Magnesium - metal donor, so it is used as an anode. Cluster floc on the bottom of the tank - no scum, and the result of the galvanic couple (anode is gradually degraded, its oxides are deposited).
The operating principle of the galvanic couple is based on the difference of potentials of copper and magnesium - it is fixed at each metal. The solution between the electrodes arises galvanic electric current - directed movement of charged ions. Movement of the particles is promoted by two factors:
- electromotive force generated due to the difference of potentials of dissimilar materials;
- transfer of ions of water flow.
These factors are taken into account during the repair and installation of the water heater.
Electrochemical connection heater elements and plumbing and heating networks
The electrochemical series of metals copper plays a role of the aggressor, magnesium - a donor. Between the electrodes there is always steel or other metal from which the container is made. There is an additional galvanic - steel and copper. Gradually the tank walls are destroyed. Destruction insignificant large internal surface area of the donor vessel.
If the inner surface of the tank protected by a covering -. Enamel, nanosilver, biosteklokeramika etc., optimistic impression. However, the appearance on the enamel slightest scratch provokes contact with the water tank material, i.e. galvanic couple formed again. The situation is aggravated negligible surface area scanty donor. Galvanic corrosion will go full swing
- To prevent possible leakage of the tank in it introduce the magnesium anode with a high positive potential. Collapsing, the core saves the rest of the details. Remember, if the magnesium anode has worn, the electrochemical corrosion process spread to all metal parts of the heater. Regularly check the integrity of the magnesium anode.
- Enamel tanks inherent drawback: water coefficient of thermal expansion of metals is much overlaps factor. At the entrance to the water heater should check valve that does not allow water to flow from the tank. Upon heating, the water expands and deforms tank. A plurality of heating-cooling cycles forming microcracks on the enamel. Careful design manufacturers introduced into tanks accumulators - expansion tanks, water quenching of the riser strokes and protect from the effects of thermal expansion. If the node is not in the water heater, it is set independently. Pick up a model of the accumulator capacity and tank volume.
When the water heater Thermex independent repair pay attention to the integrity of the internal coating. Keep in mind, a tiny scratch on the stainless steel will quickly lead to the destruction of the water heater.
This is an exaggeration, and for every 100 liters tank is 4 liters accumulator tank. But in any case, will be present stock.
Above we mentioned that the ions are transported water flow, contributing to the destruction of galvanic couples. To reduce the risk of rapid wear of the heater Building Regulations (SP 40-108-2004) recommends:
- If it is impossible to avoid a combination of aluminum (steel) and copper, copper elements are arranged downstream.
- Direct contact of dissimilar metals is inadmissible. Between them, put bronze components: valves, check valves and so on. In an extreme case include setting the magnesium anode for protection.
With regard to the water heater is meant that the combination of water heaters with aluminum fittings or radiators unacceptable. Copper pipe outlet of the tank, the copper channels bimetallic heating radiators and similar extend the life of heating appliances.
Choosing a heater with an aluminum tank, remember, any material except the galvanized steel and magnesium, being aggressive. The walls of the tank are gradually destroyed. Technical features water heater Thermex - steel tanks, galvanized or enamelled.
Attention! When operating the magnesium anode collapses to form flakes, settling on the bottom of the tank. Periodically replace the rod.