In detail: do-it-yourself cast-iron battery repair from a real master for the site my.housecope.com.
Everyone knows what cast-iron radiators look like. They are rightfully considered to be long-livers in the heating market. Invented back in 1855, they are still popular with buyers. Despite the huge selection of imported and domestic radiators of various shapes and designs, many still stop at cast iron models. After serving for some time, the batteries begin to leak, they heat up worse. Is it better to change or repair them? Experts believe that repairing cast iron batteries makes sense. If they are put in order, then the replacement can be postponed for several more years.
The radiators are of a sectional design. In appearance, the sections resemble metal columns, inside which channels for the coolant are provided. These elements are connected to each other using a nipple system. The joints are sealed with paronite or rubber gaskets. The height of the devices is 350-1500 mm, the depth reaches 65-500 mm. The power of the radiators depends on the number of sections and the heat transfer area. In rooms, cast iron batteries are placed under windowsills. Usually wall mounts are brackets, but there are floor models with legs.
Depending on the model, cast iron radiators have a power of 100-300 watts. Approximately 25-35% of heat is transferred using radiation (radiation), part - convectively. Thanks to radiation, heating is of a better quality: the radiator heats objects, and not just air. Warm air layers rise upward, and radiation provides heating to the lower part of the room. This creates the most comfortable temperature regime.
Video (click to play).
Cast iron tolerates the alkaline medium of the coolant well, is weakly corrosive and has high mechanical strength. Heating devices have a simple design and are very durable, so breakdowns due to common wear and tear of metal are a rare occurrence. A striking example of a potentially possible service life is the working pre-revolutionary batteries preserved in the homes of some Petersburgers. But cast-iron batteries also have weak points, it is in them that the "root of evil" lies.
Cast iron batteries are large and heavy, which becomes a problem during installation. The slightest flaws in the installation can lead to operational malfunctions. If you do not take care of a sufficient number of powerful brackets, batteries can warp over time, which will also lead to negative consequences.
Insufficient resistance to high pressure and water hammer
Cast iron has good technical and operational characteristics, but the load that domestic heating networks can create may turn out to be too large. Due to water hammer, leaks are possible at the joints of the sections.
Together with hot water, impurities, small particles of dirt, rust circulate through the pipes, which leads to blockages in the internal channels. Batteries must be washed in a timely manner, otherwise malfunctions in their operation are inevitable.
Wear on split gaskets and threaded nipples
Joints are always a "risk factor". Nipples and gaskets are much less durable than cast iron. They need to be replaced periodically. After that, you can forget about the problems with heating for a long time.
If during the heating season the room temperature is lower than usual, check how the neighbors are doing. If they have no complaints, it's time to start heating. Perhaps a simple canal flush will solve the problem.
A plaque appeared on the radiator
It usually forms at the joints. The reason is the low quality of the coolant.When the gaskets wear out, they allow fluid to pass through. After drying, a scum-like coating remains.
The most obvious sign of malfunctioning is the appearance of leaks. The repair involves sealing and applying a metal clamp. If there are several leaks in the radiator, it is better to replace the device.
The leak is eliminated with a regular bandage or strip of cloth and epoxy glue. The bandage is impregnated with glue and wound tightly over the leak. After the glue dries, the repaired area is painted in the color of the battery. This "ambulance" ensures tightness for 1-2 years.
Applying a temporary clamp to the leak
If the bandage is not suitable for urgent repairs, you can cut a small piece of dense rubber and tighten it over the leak.
Installing a metal clamp
The clamp is a metal ring with sealing plates attached with two bolts. Next, we will take a closer look at this repair method.
It is a plasticine-like sealing compound. The technology of application is simple: the welding is kneaded to a homogeneous mass and glued to the place of damage. Cold welding tolerates high temperatures well, therefore it is suitable for repairing small leaks.
Typically, the leak is easily identified. If there are difficulties with diagnostics, the radiator is removed, immersed in a bath of water and monitored for the appearance of air bubbles. The place from which they rise is not airtight. When a leaking area is identified, materials and tools should be prepared:
thin metal cable;
putty;
a piece of cloth;
metal clamp or something that can replace it: electrical tape, wire, etc.
Cover the floor with oilcloth, put a rag on top to absorb excess moisture.
With a thin cable, clean the leaking section of the radiator to metal, degrease with any solvent or gasoline.
Cover the leak. Apply the putty to a strip of fabric and wrap tightly over the damaged area in several layers. If metal powder or epoxy is used as a putty, then 2-3 layers are enough. If zinc white is 4-5. Cold welding is also used as a putty. No fabric is needed for her.
Place a metal clamp on the putty, tighten with bolts and nuts. Make sure the connection is on the opposite side of the leak. If electrical tape is used instead of a clamp, wind it in several layers and secure with wire.
Repairing cast iron batteries is not difficult, does not require special knowledge and skills, but if you have doubts about your abilities or a leak is really serious, it is better to contact a specialist. It makes sense to replace old radiators, which have leaked more than once, otherwise their repair will become a constant activity during each heating season.
Describe your question in as much detail as possible and our expert will answer it
I begin preparations for the new heating season as soon as the previous one ends. First, I examine the radiators for rust and smudges. In the summer, I start repairing, if such is required. Usually I manage on my own, and the work is limited to cold welding and tinting. There was a case when a rubber gasket came out at the connection of two sections of a new battery, then they called the master to replace it. But I consider the clamps to be a temporary measure, which is used when it is impossible to turn off the heating and replace a section or the entire battery. In the summer, I always change the problem area, so as not to inadvertently flood my neighbors for the next heating season.
Thank you very much for the useful site!)
what is the size of the gaskets? (inner and outer diameters? What is the thickness of the gaskets separately from rubber and separately from paranite?Now I have made a die-cut and will try to do it from car cameras.
Weak heat transfer from radiators during the heating season can occur for various reasons. The most popular of these is depressurization or reduced flow capacity in cavities. It is not always possible to get rid of such elements of the system, so you can carry out an independent repair of the heating battery. With its help, in many cases it is possible to restore the functionality of a failed node.
In modern living quarters, there are several types of radiators that effectively cope with their task. The main difference between the two is the material used. It is customary to use the following types:
Cast iron. Affordable, but heavy. They are used more often in apartment buildings.
Aluminum. They are in demand in low pressure systems. They do not tolerate pressure drops and water hammer.
Bimetallic. They have a long service life. They are quite expensive.
Steel. They have good thermal conductivity, but are susceptible to rapid corrosion processes, which reduce the service life.
In most cases, the repair of heating radiators is effective with cast iron sections.
Homeowners usually start to worry when the radiator is leaking, and not when the first problem symptoms appear. To reduce the likelihood of failure of radiators, it is worth paying attention to the behavior of the system as a whole and its individual sections:
repair of cast iron batteries or other material may be necessary with incorrectly selected pipe diameters, with erroneously set pressure or inappropriate choice of the coolant temperature;
with a large amount of undesirable impurities in the composition of the coolant, physicochemical destruction of the material occurs from the inside of the radiator;
heating batteries will require repair when a plaque forms at the joints between the radiator sections, clogging the passage of the coolant through the system;
damage to threaded nipples leads to the repair of heating batteries;
when the heating radiator in the apartment makes noise, this does not always indicate its malfunction, but you can call the repair team to check this process;
radiators are noisy, including from formed air jams, which arise due to pipe leaks.
Leak point in a cast iron radiator
It is impossible to ignore problem radiators, as this can lead to the formation of material or physical damage, because the temperature of the coolant inside the system is very high.
The appearance of leaking spots is usually observed during peak loads on the heating system. If the heating battery leaks, we will tell you what to do next. It is easy to notice the leak by protruding droplets in a hot area or a small wet area under one of the sections.
Self-repair of a cast-iron battery will be effective in a private house or in an apartment with individual heating. In apartment buildings, it is recommended to connect specialists from the management company to the process, since the system has a higher pressure and it is not always possible to independently disconnect from the central heating.
The best solution would be to replace the old radiator with a new one.
Before work, it is necessary to reduce the pressure and temperature in the pipes, since it can be problematic to eliminate a leak in a hot cast-iron radiator. Several repair methods are used:
A hole created by corrosion or mechanical damage is better welded than cold welded. For cast iron, separate electrodes are used, and for the convenience of repair, you can remove the section, having previously blocked the riser with water.
Restoration work must be carried out after a complete seasonal heating shutdown.If the sections are built into a niche and are not supposed to be dismantled, then they must be at a sufficient distance from the wall. With dismantled elements, the restoration of cast iron batteries is usually carried out in their horizontal position. The second method is preferred. The remaining coolant is removed from the cavities and plugs or plugs are disposed of.
When unscrewing the radiators, it should be borne in mind that the plugs have a cut left-hand thread, and the cutouts have a right-hand thread.
We combine the working head of the key with the nipple in the section. We install an emphasis under the key so as not to bend it. Next, we begin to disassemble the sections. If the rusted thread does not lend itself, then this place must be warmed up with a burner or autogenous gun, spinning fire around the thread. Replacing the problem section, we return the radiator to its place.
It is advisable to prevent the formation of foci of corrosion on the outside of the radiators. To do this, it is recommended to paint them regularly. Previously, the surface is cleaned with a metal brush or sandpaper.
Separately, a few words must be said about the paint for radiators. You should choose a special non-toxic coating designed for temperature differences, with protection against corrosion and cracking, so that when heated, no toxic substances are released.
More and more often in apartments and houses you can find unconventional design of radiators. Most often we are talking about protective screens - an aesthetically designed panel that covers the radiator, but at the same time it does not interfere with convection. It is much less common for batteries to be painted in different colors. And although this is still rare in our apartments, it always looks very original and fresh.