Poor water heater performance interferes with normal life, right? Water barely pours or heats up for a long time, the burner smolders a little or pours soot ... It is necessary to somehow repair it, look for the craftsman, negotiate the price terms. And why spend money if cleaning the heater is easy to do on its own?
We will tell you how to clean your Bosch geyser with your own hands without contacting gas workers. To completely disassemble and clean the device, a “home” set of tools is enough. You will learn all about dismantling the working blocks of the column, the rules for cleaning its burner, heat exchanger and chimney from our article.
What pollutes the Bosch geyser?
The reasons for the pollution of a flowing water heater are related to its functions and principle of operation:
- Flowing water.The column heats the water flowing through its heat exchanger, which brings mineral inclusions along with it. As a result, the clogging deposit settles on the walls of the heat exchanger and the pipes of the device and gradually increases.
- Gas burner. In case of defective gas combustion (see reasons below), soot and soot are formed. The latter clogs the fins of the heat exchanger and the chimney, further deteriorating the combustion of gas fuel and slowing down the heating of water.
- Poor quality tap water. Due to the stiffness of tap water during its heating, salts are released from the composition, which are deposited in the form of scale inside the pipes and heat exchanger. The thicker the scum layer, the narrower the lumen of the pipe and the worse it passes water.
In addition to magnesium and calcium salts dissolved in water, it contains mechanical impurities from rusting pipes. They also participate in the gradual overgrowing of the pipe channel in the heat exchanger together with scale.
As for soot, its increased formation is promoted by increased pressure on the burner, weak chimney draft (low height, cracks, lack of thermal insulation, etc.), lack of supply air (PVC windows are sealed, but there is no supply valve).
The deposition of soot is also facilitated by the use of forced exhaust in a room with a running water heater (causes a lack of oxygen), dustiness in the room (dust enters the burner, which does not cause complete gas combustion).
Filters and magnetic traps, fine adjustment of the burner and air draft will slow down the process of clogging the column, but they will not completely exclude it
Since scale formation is more intense when water is heated above 60aboutC, some owners of German water heaters set a low burner heating temperature. However, as a result of this, the working cavities of the heat exchanger gradually overgrow with a greenish bloom from condensate.
As a result, the removal of flue gases deteriorates, which contributes to the accelerated formation of soot. The heat exchanger clogged with soot heats the water very badly - soot is a good heat insulator.
Signs of gas heater clogging
The need for cleaning the Bosch flowing gas column is determined by the decrease in the instrument's performance.
Cleaning is required if:
- the water heater simply does not start;
- it turns on, but does not work for long and turns off on its own, while there is no shortage of water and gas;
- the column heats up properly, but the water heats up noticeably worse than before;
- the water pressure at the outlet of the heating device is weaker than at the entrance to the heat exchanger;
- Frequent activation of the overheating sensor, although the water heater is operating under medium load.
Ignition nozzle blockage. It is impossible or difficult to ignite the column if the pilot jet is clogged, which is why the device ignites the fuel with a delay - with a characteristic pop. A sign of contamination of the igniter is a weak yellow wick, although it should be blue.
Soot in the chimney. If the burner flares up, but extinguishes almost immediately after ignition, the smoke channel of the water heater is dirty. The chimney passability is significantly reduced due to soot and soot deposits accumulated over the years of using the column. However, the chimney of the columns in the apartments is more often polluted with volatile debris.
Preventive cleaning of the gas water heater must be carried out regularly, the recommended frequency is every two years. Otherwise, the column will work worse, aimlessly spending natural gas and water
Weak air supply. For natural draft even in a small gas water heater supply air is necessary. And modern homes are equipped with airtight window and interior door blocks.
To solve the problem of insufficient traction will allow ventilation valves that are built into the window frames, wall inlets, as well as ventilation grilles in the interior doors.
Scale in the heat exchanger. Inadequate heating of the water in the flowing gas heater causes a reduced flow area of the heat exchanger pipe caused by a scale layer. And the more limescale has grown, the lower the water pressure after heating in the column against the background of normal pressure at the inlet to the heating device.
Soot overgrowth. The greatest amount of soot accumulates in the central part of the finned heat exchanger, transferring heat to running water and contributing to overheating of the side sections of the heat exchange unit.
Uneven heating of the heat exchanger causes the overheating sensor to respond quickly. Most often, soot pollution of fins develops together with chimney clogging.
How to remove the casing of a Bosch water heater?
The decorative and protective casing of the column is easy to remove:
- you need to unfasten the round adjustment knobs by pulling them towards you;
- move the rectangular gas adjustment knob to the body cavity (the position is “set on fire”). Note that not every Bosch water heater model has such a handle;
- Use a Phillips screwdriver to unscrew the two screws securing the casing to the column frame. They are located below, on the sides of the device.
It remains with both hands to gently push the bottom of the casing of the heater toward you. Then lift up, completely remove and set aside. Now you can visually assess the contamination of the device, determine the scale of the treatment work.
How to remove and clean the ignitor?
Evidence of contamination of the ignition tube: the flame of the ignition spontaneously extinguishes; a weak flame tongue rises without displacement to the burner due to insufficient gas pressure (if the pressure of the main or balloon gas has weakened, then the igniter has nothing to do with it).
Cleaning the igniter will stabilize the ignition, prevent popping and soot formation on the heat exchanger grilles
Please note: before you start cleaning the clogged igniter of the Bosch geyser, be sure to double check that the gas valve of the appliance is closed!
Necessary tools: a flat (minus) screwdriver or thin pliers with curved “lips” (platypuses). Remove the ignition tube carefully enough without pushing through the jacket of the heat exchanger.
The order of dismantling the ignitor of the water heater:
- Upper end. Pull up the bracket holding the flared edge of the ignition tube at the end of the burner. Slightly unclip the bracket, then slide it up with platypus pliers or pry it with a screwdriver until it is completely removed;
- Lower end. It is necessary to squeeze the edges of the bracket fixing the ignitor;
- Removing the igniter. Having freed the ends of the tube, it remains to lift it up and remove it with a movement “towards itself”.
To clean the cavity of the ignition tube, you will need a piece of not too rigid wire, on which a piece of lint-free cloth (for example, microfiber cloths) is clamped. We stretch a home-made "brush" inside the tube, then lightly tap it and blow it.
The igniter tube is made of aluminum, it is quite simple to crush it. Therefore, cleaning, and especially tapping, must be done carefully, without undue stress
It is also necessary to clean the tungsten spring on the underside of the tube. This will provide a quick ignition from the piezoelectric element. Finally, it is required to clean the nozzle at the lower point of connection of the ignition tube and the electrode located in front of the upper outlet of the tube. They should be wiped with microfiber or other lint-free cloth.
The installation in the column of the cleaned pilot is carried out in the reverse order of dismantling. If cleaning is performed efficiently, then the flame from a lit ignition tube will be almost invisible.
Cleaning the Bosch Geyser Heat Exchanger
If, after removing the casing of the heater and inspection of the heat exchanger unit, soot contamination is detected, it will need to be dismantled and completely flushed. It is necessary to clean the smoked heat exchanger by removing it from the gas column.
After cleaning, the heat exchanger will not look new. The task here is to eliminate the maximum amount of contamination from the inner plane of the shell and, especially, from the grille
The first step is to close the shut-off valves for water and gas supply to the heating column. If you intend to completely remove the device and dismantle the heat exchanger by putting the column on the table (it will be more convenient) - disconnect the gas supply hose, water inlet and outlet, then remove the device from the mounts.
However, there is no need to completely remove the water heater; you can remove the radiator of the heat exchange module at the installation site. Consider this maintenance option in detail.
Dismantling the water heat exchanger
The necessary tools are flat (minus), Phillips (plus) screwdrivers and platypus pliers.
The pipes for supplying and discharging water from the heat exchanger are fixed with brackets, which are easy to remove with a flat screwdriver and thin-lipped platypus pliers
Attention: with an externally large size, the heat exchanger is hollow inside and light. When disassembling, handle it carefully, otherwise remember the side!
The procedure for extracting a heat exchanger using the example of Bosch WR13-2B:
- Overlap shut-off tap of cold water at the feed to the water heater;
- Removing the column cover. Pull out the adjustment knobs by pulling it towards you, unscrew the two self-tapping screws on the sides at the bottom of the case, slide the lower part of the casing towards you, lift and remove from the upper hooks;
- Pulling the bracket securing the tube to the water distribution unit. Pry off the bracket with a screwdriver, remove it with the "platypus", move the tube to the right. Before removing the locking bracket, substitute a wide container under the drain for about a liter of water from the heat exchanger;
- Removing the sensor terminals from the heat transfer tank and housing. Located on the left side of the device, wires go to them;
- Pulling the staples fixing the water supply pipe at the inlet to the heat exchanger (located to the right under it). The principle is the same - to pry off with a screwdriver, carefully pull out with platypus pliers, then remove the tube completely;
- Removing the protective screen in front of the ignition group by unscrewing two screws with a Phillips screwdriver. After you need to remove the ignition group from the nest, remove it;
- Pulling the brace from the union hose at the outlet of the heat exchanger radiator (screwdriver and duckbill), disconnecting the hose. Do not forget to drain the water first by opening the tap on the sink;
- Unscrewing two screws securing the main burner on the sides;
- Unscrewing two screws securing the gas manifold under the burner (located under it, in the center);
- Removing the guide rail holding the heat exchanger from above. There are two side screws for a Phillips screwdriver. Unscrew and remove the bar.
It remains only to remove the heat exchanger with the burner. Place your palms of your hands under the burner on its sides and firmly, not without unnecessary efforts, press the heat exchanger radiator shell with your thumbs. Lift them up, then slide the upper part of the heat exchanger “towards you” and remove both modules to the outside.
Cleaning the heat exchanger and main burner
To clean and rinse, the heat-exchange radiator must be placed in a bath or other suitable container size. In order not to scratch the bottom and walls of the bathroom bowl, you should first lay a cloth in it.
Using ordinary detergents, hot water and a long-brushed brush, rinse off the soot from the inside and outside of the unit. Before reassembling into a column, it must be dried.
When reassembling, note that the slight inclination of the lateral fins should be oriented towards the center of the main burner.
If the burner is soiled with soot, then it must be disassembled and cleaned. The fasteners of the burner sections (Venturi tubes) are bolted; they are easy to unscrew.
Professional cleaning of a dusty burner is carried out with compressed air, and at home - with a soft brush and a vacuum cleaner. In case of serious contamination, wash with soapy water and wipe with a lint-free cloth, then dry and reassemble the burner.
Descaling process
To eliminate deposits of magnesium and calcium salts (scale) in the heat exchange radiator pipe, it will be necessary to remove it and prepare it for washing with an acid-containing solution. Note that soot must be cleaned before descaling.
It is unprofitable to spill the prepared citric acid-based cleaning fluid. Be sure to use a funnel to fill the heat exchanger tube completely
Do not attempt to tear or scale inside the copper tube of the heat exchanger! Firstly, this is an almost useless activity, because the bulk of the mineral deposits in the depth of the pipe will be unattainable for stripping. Secondly, scratching the thin walls of the tube will weaken its strength and cause deformation.
The following tools will help remove scale in the column:
- Limescale preparationssold in hardware stores. The procedure for preparing each product for flushing operations is indicated in the manufacturer's instructions;
- Lemon acid. Since the volume of the tube in the design of the heat exchanger is about a liter (the exact volume is indicated in the instructions for the device), you will need to prepare a hot solution in the proportion of 100 g of citric acid per 0.5 l of water in a volume of 700-800 ml;
- Nine percent vinegar. Vinegar diluted in three parts of warm water is able to remove scale in the column heat exchanger. The required volume of solution is 700-800 ml.
No other means like Coca-Cola or home-made solutions based on active acids (hydrochloric, nitric, sulfuric, etc.) can be used to clean scale - soda does not work, and acid solutions can damage the tube.
It is necessary to turn the heat exchanger with the radiator plates down and the I / O of the tube up, insert a funnel into the tube and pour the prepared cleaning solution. Chemical descaling will take several hours, therefore it is more convenient to fill the solution with a heat transfer radiator from evening to morning.
If the column that has been regularly used for several years has not been descaled before, then the mortar cleaner must be changed two to three times until it is completely cleaned. Otherwise, although the scale layer is reduced, it will not be completely eliminated.
After waiting for the period necessary for the destruction of scale deposits (more than 4 hours), it is necessary to pour out a cleaning agent and rinse the tube with a large volume of clean water.During the flushing process, it is important to bring out all fragments of the sludge separated from the pipe walls.
The following article will familiarize you with the causes of water overheating by a column and ways to fix the problem, which all independent home masters should read.
Step-by-step dismantling of the Bosch water heater for cleaning the heat exchange unit and the main burner:
Video on cleaning a dusty main burner column from a home master:
It is necessary to clean the gas water heater from soot and scale every two years of operation, otherwise the performance of the device will sharply weaken. If the warranty period agreed upon by the manufacturer has expired, it is not necessary to contact the gas service with which a contract has been concluded for servicing the equipment.
It happens that there is no particular need to involve gas workers in descaling and carbon deposits. In this case, only male hands, free time and a simple tool are needed. Follow the instructions above and you will succeed!
Want to talk about how to clean your own gas column yourself? It is possible that the subtleties of the cleaning process known to you will be useful to site visitors. Please leave comments in the block below, post photos and ask questions about the topic of the article.