Old heating radiators need periodic coverage in order to look presentable. It is important to choose the right paint for radiators so that it lasts longer and does not lose color under the influence of heat. If it is easier to choose a coating for cast iron batteries, then it is difficult to paint aluminum radiators at home, since in the factory they are treated with a powder method and exposed to high temperatures. It is almost impossible to repeat such conditions at home.
What paint to choose for radiators
Painting radiators is necessary to create an air- and moisture-proof layer on the metal surface so that oxygen and occasional drops of water do not cause corrosion. Different paints cope with this task in different ways. It should also be taken into account that the batteries are hot in working order - not all compositions are capable of withstanding high temperatures for a long time, and painting them every year is unprofitable and time-consuming.
When selecting paints and varnishes, the surface on which the coating will be applied is taken into account. Stainless steel and aluminum are materials that do not corrode, so products made from these metals have a long service life. The only question is with painting, since any composition will not last long - it will peel off due to low adhesion (adhesion) to the metal surface. This happens because an oxide film forms on the surface (in aluminum radiators, for sure), which rejects ordinary paint. In order to properly coat aluminum, you need a different primer and special paints.
General requirements for paints and varnishes:
- heat resistance within 80 - 100 degrees;
- non-toxic - no harmful volatile compounds should be released when heated;
- moisture resistance, since the radiators will be wiped with a damp cloth from dust;
- abrasion resistance;
- the composition should dry quickly and form a resistant film on the metal.
If you neglect the requirements of heat resistance, such a coating will quickly turn yellow or peel off. Both the pigments and the bonding material must withstand high temperatures.
If the paint is very shiny after coating the batteries, it will highlight all the irregularities that are not uncommon on cast iron products. Therefore, it is advisable to choose a paintwork with a matte shade that will not create glare. At the same time, rubbing irregularities on cast iron is highly discouraged, as this leads to abrasion of the metal and the appearance of a leak.
The faster the paint dries, the stronger the smell it exudes in this short period of time, therefore it is undesirable to work indoors - you should open windows or vents, use a respirator for construction work.
Do not use pentaphthalic compounds for painting batteries, for interior work, water-based, nitrocellulose.
Acrylic
Acrylic paint for radiators is the most optimal and reliable option. It dries quickly and does not emit strong odors.The coating on the batteries lasts a long time and does not change color when exposed to heat. To do this, you need to buy formulations marked "for radiators".
Acrylic enamel for radiators is usually sold in white. To give any shade, it must be tinted - add the desired pigment. You can mix and match the composition on a special paint mixing machine in the supermarket. The plus is that if you need a little more of the same composition, the device remembers how much enamel and powder you need to add to get the same shade.
Water-based
It is not recommended to cover batteries with water-based paint, as it is not durable and will last for a year or two at best. If you count on long-term operation, you need to select something more durable.
Alkyd
Alkyd paint with titanium beryl or silicone is considered very resistant and can withstand temperatures up to 600 degrees. It is used for painting all heated surfaces - radiators, stoves, fireplaces, chimneys.
It is necessary to work with alkyd paint in a well-ventilated area, since when it dries, toxic substances are released that can lead to poisoning. After drying, the coating is not dangerous.
Oil
Oil paints are resistant to mechanical stress and abrasion, but they do not withstand high temperatures, so they are not recommended for use as a coating for batteries. Especially if the radiators warm up well in winter.
Such a coating dries for a long time, therefore it is impossible to carry out work in a closed room with a working radiator. Heat transfer is reduced, as the layer of oil paint is 1 - 2 mm. It will not be possible to save on heat carriers.
Oil solutions are composed of organic substances, so they quickly change color - white batteries turn yellow or gray. The radiators will have to be repainted due to cracks and colors every 2 - 3 years. If you save money and buy a non-heat-resistant oil paint, it will crack in a year.
Serebryanka
A mixture of aluminum powder, bitumen varnish and thinner - silver paint. If it is not necessary to use white, at home you can prepare a composition from purchased components that will withstand temperatures up to 400 degrees. This is often done to cover batteries located in utility rooms - sheds, garages.
It is better not to buy ready-made silverware - it does not differ in heat resistance. You need to take separately bituminous varnish 577 brands and PAP-1 - aluminum powder, mix them and paint.
Choice of colors
For acrylic and alkyd enamels, there are a huge number of pigments to give the radiator one color or another, so it all depends on the design of the room. If the color scheme is not so important, you can do with a white tone - it reflects warmth best of all. True, you will have to wash the battery more often and any scratches will be immediately noticeable.
Without the use of a special primer and preliminary cleaning of the surface from the old coating, the color may not correspond to the selected one. Therefore, it is recommended to carry out all work in strict accordance with the technology. Then the color will please, and the paint will last for a long time.
What tools are required
For painting radiators, you need to prepare thin straight brushes and curved ones to get to the hard-to-reach places between the ribs. If you can find brushes with lateral hair, it will make the job easier.
To remove old paint, you need a wire brush and a drill. The fastest way for them to remove the old layer. You can use the manual one, but it will take a long time. If there are places that have begun to rust, a metal brush is a must.
You will need coarse sandpaper to clean the residues.If there are no tools, you can buy special solvents that are applied to the surface, and then they are washed with old rags or paper. To degrease a new radiator, you need to prepare a little alcohol or gasoline to ensure good adhesion of the paint and the metal surface.
It is advisable to lay a newspaper on the floor so as not to splash the coating. If the paint for heating radiators is in a can, it is better to remove the heating elements, take them outside and carry out work there.
An atomizer is a convenient thing, but not everyone can find it on the farm. With the help of it, the process of applying paints and varnishes will take place faster and more evenly.
To protect the respiratory system, you need to buy a respirator, especially if you have to work with alkyd paint.
Surface preparation
The surface of the radiator must be properly prepared for painting. If the preparatory measures are neglected, in some places the coating will begin to lag behind the metal and swell. Moreover, the corrosion process will begin inside under the paint layer and the radiator will soon have to be replaced. If the batteries are old and have a layer of rust on them, they need to be cleaned to a shine, and then any remnants of oxidized metal should be removed with a rag or brush.
Removing old paint
- Chemical. Buy a gel or spray remover from a store. It is better to apply the gel, as it does not run off. Remove the softened layer with a brush or spatula. The disadvantage of this method is that it will be difficult to clean the surface between the ribs of the batteries, some chemicals corrode the hemp, which is used in cast-iron radiators. At the end, the radiator must be washed with soapy water and dried before the next step. Gloves and goggles must be worn when handling chemicals.
- Thermal. To do this, you will need a high-power building hair dryer or, better, a blowtorch for baking the surface, a metal brush with a drill and an old rag. The batteries are heated until the old paint begins to peel off, then it is cleaned off with a spatula or brush.
- Mechanical. Drill attachments, file, sandpaper are used.
If you leave traces of the old coating and apply a new one over it, the paint will swell in these places and the work will have to be done again.
Surface sanding
Sanding - processing with sandpaper - is carried out if the old paint adheres well to the metal, but at the same time has lost its shine and needs to be renewed. You can walk over the old layer so that the new coating adheres well to it. In this case, you need to use a similar paintwork that does not differ in composition from the previous one. It is necessary to process all hard-to-reach places.
Primer
New radiators must be primed to ensure high adhesion and prevent rust. Before applying the primer, the surface is degreased with alcohol-containing substances or gasoline using a rag.
The primer material should match well with the type of paint chosen and also have anti-corrosion properties if applied directly to the metal substrate. After surface treatment - external and internal - the soil layer should dry properly. Only then can you start painting the batteries.
Painting technology
Before painting the battery, you need to prepare your brushes. They are fluffed so that all loose hairs fall out, which can spoil the appearance. The radiator enamel is poured into a plastic container, a brush is dipped in and the paint is applied to the surface. You can start from hard-to-reach places using a curved brush.This is convenient as the outside will be clean and will not stain your hands and clothes.
Hand movements should be carried out from top to bottom in order to immediately eliminate the resulting drips. In acrylic and alkyd paints, they quickly harden and spoil the even surface.
The paint is applied in two or three layers. This is the optimal amount, since then heat transfer will begin to decrease, and this is completely unnecessary. It is necessary to take into account the drying speed of the layers - the information is on the paint can. Usually a new layer is applied after 2-3 hours.
If you paint over the old paint, through one layer the old coating will shine through, and the surface will be painted unevenly.
It is more convenient to spray paint from a can - it has already been diluted to the desired consistency. If using a spray bottle, add 10% of a suitable solvent to the enamel so that it does not clog the spray bottle.
Amount of paint
The manufacturer usually indicates which heating area a given amount of paint is intended for. It is taken into account that more paints and varnishes are required for the first layer, and less for the second and third. For a typical single-section cast-iron radiator of the MS-140 brand with an area of 0.2 - 0.25 sq. m consumption will depend on the type of paint. Going to the supermarket, you need to calculate how many ribs each battery has and how many layers you plan to paint. The managers will calculate the amount of paint to be enough for all the details. It is better to round it up, so as not to buy 100 ml of coating, if suddenly it is not enough.
Can hot batteries be painted
Most radiator paints tolerate high temperatures well, so they can be used in winter when the batteries are on. The most suitable options would be acrylic compositions - with a solvent or water-dispersion, since they dry quickly and do not emit an unpleasant odor. If you paint the surface of the radiator in the morning and open the window, by the evening you can safely be in the room without fear of poisoning.
To make the battery paint dry faster, the subsequent layers are applied after the previous one dries a little. Taking into account the fact that acrylic compounds dry quickly, this does not take much time, and the hot surface will speed up the process.
