Contents
Sometimes it becomes necessary to adjust the temperature in each particular room. This can be done by installing a thermostat for a heating radiator. This is a small device that regulates the heat transfer of a heating battery. It can be used with all types of radiators, except for cast iron ones. One important point – the device can lower the initial temperature, but if there is not enough heating power, it cannot increase it.
The design of thermostats for heating radiators
The thermostat for a heating radiator consists of two parts – a valve (thermal valve) and a thermostatic head (thermostatic element, temperature controller). These products are produced for different sizes of pipes and different types of heating systems. The thermostatic head is removable, you can put regulators of different types and even different manufacturers on the same valve – the seat is standardized.
Both valves and regulators are different, so before you install a thermostat for a heating radiator, you will have to get at least a little familiar with its structure, functions and types.
Thermal valve – structure, purpose, types
The valve in the thermostat is very similar in structure to a conventional valve. There is a seat and a shut-off cone that opens/closes the gap for the flow of coolant. The temperature of the heating radiator is regulated in this way: the amount of coolant passing through the radiator.
Different valves are installed on single-pipe and two-pipe wiring. The hydraulic resistance of the valve to a single-pipe system is much lower (at least twice) – this is the only way to balance it. It is impossible to confuse the valves – it will not heat. For systems with natural circulation, valves for one-pipe systems are suitable. When they are installed, the hydraulic resistance, of course, increases, but the system will be able to work.
Each valve has an arrow indicating the movement of the coolant. During installation, it is installed so that the direction of flow coincides with the arrow.
What materials
The valve body is made of corrosion-resistant metals, often additionally coated with a protective layer (nickel or chrome plated). There are valves from:
- bronze (with nickel and chrome plating);
- brass (coated with a layer of nickel);
- of stainless steel.
The bodies are usually brass or bronze with nickel or chrome plated
It is clear that stainless steel is the best option. It is chemically neutral, does not corrode, does not react with other metals. But the cost of such valves is high, it is difficult to find them. Bronze and brass valves are about the same in terms of service life. What is important in this case is the quality of the alloy, and well-known manufacturers carefully monitor it. Whether or not to trust the unknown is a moot point, but there is one point that is better to track down. There must be an arrow on the body indicating the direction of flow. If it is not there, you have a very cheap product that is better not to buy.
By way of execution
Since radiators are installed in different ways, the valves are made straight (through) and angular. Choose the type that will be better for your system.
| Name/company | For which system | Du, mm | Housing material | Operating pressure | Price |
|---|---|---|---|---|---|
| Danfos, angled RA-G adjustable | single pipe | 15 mm, 20 mm | Nickel plated brass | 10 Bar | 25-32 $ |
| Danfos straight RA-G adjustable | single pipe | 20 mm, 25 mm | Nickel plated brass | 10 Bar | 32 – 45 $ |
| Danfos, angled RA-N adjustable | two-pipe | 15 mm, 20 mm. 25 mm | Nickel plated brass | 10 Bar | 30 – 40 $ |
| Danfos straight RA-N adjustable | two-pipe | 15 mm, 20 mm. 25 mm | Nickel plated brass | 10 Bar | 20 – 50 $ |
| BROEN , straight fixed | two-pipe | 15 mm, 20 mm | Nickel plated brass | 10 Bar | 8-15 $ |
| BROEN , straight fixed | two-pipe | 15 mm, 20 mm | Nickel plated brass | 10 Bar | 8-15 $ |
| BROEN , corner adjustable | two-pipe | 15 mm, 20 mm | Nickel plated brass | 10 Bar | 10-17 $ |
| BROEN , corner adjustable | two-pipe | 15 mm, 20 mm | Nickel plated brass | 10 Bar | 10-17 $ |
| BROEN , straight fixed | single pipe | 15 mm, 20 mm | Nickel plated brass | 10 Bar | 19-23 $ |
| BROEN fixed angle | single pipe | 15 mm, 20 mm | Nickel plated brass | 10 Bar | 19-22 $ |
| OVENTROP , axial | 1 / 2 “ | Nickel-plated brass, enamelled | 10 Bar | $ 140 |
thermostatic heads
There are three types of thermostatic elements for heating thermostats – manual, mechanical and electronic. All of them perform the same functions, but in different ways, provide different levels of comfort, and have different capabilities.
Manual
Manual thermostatic heads work like a regular tap – turn the regulator in one direction or another, passing more or less coolant. The cheapest and most reliable, but not the most convenient devices. To change the heat transfer, you must manually turn the valve.
These devices are quite inexpensive, they can be placed at the inlet and outlet of the heating radiator instead of ball valves. Any of them can be adjusted.
Mechanical
A more complex device that maintains the set temperature in automatic mode. The basis of this type of thermostatic head is a bellows. This is a small elastic cylinder that is filled with a temperature agent. A temperature agent is a gas or liquid that has a large coefficient of expansion – when heated, they greatly increase in volume.
The bellows supports the stem, blocking the flow area of the valve. Until the substance in the bellows is heated, the stem is raised. As the temperature rises, the cylinder begins to increase in size (gas or liquid expands), it presses on the rod, which more and more blocks the flow area. Less and less coolant passes through the radiator, it gradually cools down. The substance in the bellows also cools down, due to which the cylinder decreases in size, the rod rises, more coolant passes through the radiator, it starts to warm up a little. Then the cycle repeats.
gas or liquid
With such a device, the room temperature is fairly maintained at exactly +-1°C, but in general the delta depends on how inert the material in the bellows is. It can be filled with some kind of gas or liquid. Gases respond faster to temperature changes, but are more difficult to produce technologically.
Liquids change volumes a little slower, but they are easier to produce. In general, the difference in the accuracy of maintaining the temperature is about half a degree, which is almost impossible to notice. As a result, most of the presented thermostats for heating radiators are equipped with thermal heads with liquid bellows.
With remote sensor
The mechanical thermostatic head must be installed so that it is directed into the room. This way the temperature is measured more accurately. Since they have a fairly decent size, this method of installation is not always possible. For these cases, you can put a thermostat for a heating radiator with a remote sensor. The temperature sensor is connected to the head with a capillary tube. You can place it at any point where you prefer to measure the air temperature.
All changes in the heat transfer of the radiator will occur depending on the air temperature in the room. The only disadvantage of this solution is the high cost of such models. But the temperature is maintained more accurately.
| Name/company | Setting range | Operating temperature range | Management type | Functions/Purpose | Connection type | Price |
|---|---|---|---|---|---|---|
| Danfoss living eco | from 6 ° C to 28 ° C | from 0 ° C to 40 ° C | Electronic | Programmable | RA И M30X1,5 | $70 |
| Danfoss RA 2994 with gas bellows | from 6 ° C to 26 ° C | from 0 ° C to 40 ° C | Mechanical | For all radiators | clip-on | $20 |
| Danfoss RAW-K with liquid bellows | from 8 ° C to 28 ° C | from 0 ° C to 40 ° C | Mechanical | For steel panel radiators | M30x1,5 | $20 |
| Danfoss RAX with liquid sphon | from 8 ° C to 28 ° C | from 0 ° C to 40 ° C | Mechanical | For design radiators white, black, chromed | M30x1,5 | $25 |
| HERZ H 1 7260 98 with liquid sphon | from 6 ° C to 28 ° C | Mechanical | M 30 x 1,5 | $11 | ||
| Oventrop “Uni XH” with liquid sphon | from 7 ° C to 28 ° C | Mechanical | zero mark | M 30 x 1,5 | $18 | |
| Oventrop “Uni CH” with liquid sphon | from 7 ° C to 28 ° C | Mechanical | without zero mark | M 30 x 1,5 | $20 |
Electronic
The size of the electronic thermostat for the heating radiator is even larger. The thermostatic element is even bigger. In addition to the electronic filling, two batteries are also installed in it.
The movement of the stem in the valve in this case is controlled by a microprocessor. These models have a fairly large set of additional features. For example, the ability to set the temperature in the room by the hour. How is it fashionable to use? Doctors have long proven that it is better to sleep in a cool room. Therefore, at night, you can program the temperature lower, and in the morning, when it’s time to wake up, it can be set higher. Comfortable.
The disadvantage of these models is their large size, the need to monitor the discharge of batteries (enough for several years of operation) and the high price.
How to install correctly
They put a thermostat for a heating radiator at the inlet or outlet of the heater – there is no difference, they work with equal success in both positions. How to choose a place to install?
According to the recommended installation height. This item is in the technical specifications. Each device goes through a factory setting – they are calibrated for temperature control at a certain height and usually this is the upper radiator manifold. In this case, the heat regulator is installed at a height of 60-80 cm, it is convenient to manually adjust it if necessary.
If you have a lower saddle connection (pipes fit only from the bottom), there are three options – look for a device with the ability to install at the bottom, install a model with a remote sensor, or reconfigure the thermal head. The procedure is simple, the description must be in the passport. All you need is to have a thermometer and turn the head in one direction at certain moments, then in the other direction.
The installation process itself is standard. The valve is threaded. Appropriate fittings are selected under it or a reciprocal thread is cut on a metal pipe.
One important point that those who want to install a thermostat for a heating radiator in apartment buildings should keep in mind. If you have a single-pipe wiring, they can only be installed if there is a bypass – a pipe section that stands in front of the battery and connects the two pipes to each other.
Otherwise, you will regulate the entire riser, which your neighbors will definitely not like. For such a violation, a very substantial fine can be issued. Therefore, it is better to put a bypass (if not).
How to adjust (reconfigure)
All thermostats are factory set. But their settings are standard and may not match your desired parameters. If something does not suit you in your work – you want it to be warmer / colder, you can reconfigure the thermostat for the heating radiator. This must be done with the heating on. You will need a thermometer. You hang it at the point where you will control the state of the atmosphere.
- Close the doors, put the thermostat head in the leftmost position – fully open. The room temperature will start to rise. When it becomes 5-6 degrees higher than what you want, turn the knob all the way to the right.
- The radiator starts to cool down. When the temperature drops to a value that you consider comfortable, start slowly turning the knob to the right and listen. When you hear that the coolant is noisy, and the radiator starts to warm up, stop. Remember what number is on the handle. It will need to be set to achieve the required temperature.
Adjusting the thermostat for the heating battery is not difficult at all. And you can repeat this action several times, changing the settings.