Thermoheads for radiators are needed to create the optimal temperature regime in the house. Heating operation is more efficient when all heating points of the system are determined - in each individual room. Manual heating control cannot ensure high accuracy and timeliness of compensation.
Why should I install a thermostat?
When using a thermal head for radiators, the heating system becomes more efficient. The flow of hot water through the pipe decreases in a timely manner with an increase in the external air temperature, thereby reducing the heating power.
Cone valves are used in classic heating systems. Ball valves are also common, having a number of features:
- Used only in two positions: open and closed. It is difficult to set intermediate positions, and the risk of leakage outside the extreme positions of the ball also increases. Thermal heads for radiators are deprived of this.
- No automatic control, all water flow adjustments are made manually.
- The ball valve instantly applies pressure to the system, which can lead tomechanical damage to the radiator tubes and joints.
- Thermal heads for radiators use natural physical properties and can work autonomously without additional maintenance.
Device arrangement
Let's consider the insides of the thermal head for radiators. The principle of operation of the device is based on the use of physical quantities: the tensile force of the spring and the expansion of gases under the influence of temperature. Outwardly, it looks like a corrugated shell that changes in size.
The safety margin of the spring is enough for the entire service life of the device. Thermal heads can be without power and with it: from the battery and the network. Simple designs are preferred, but remote sensor systems are more accurate.
For the temperature converter, sensitive elements are used: solid (springs or plates), liquid (the principle of operation is like a thermometer), gas (substances lighter than air). The heating agent in the radiator can be water or a specialized fluid with additives. The last point to consider when choosing the type of thermal head.
What to consider?
With proper execution of the heating system, a thermal head is used for the radiator. Feedback from experienced plumbers shows that automatic adjustment saves money, resource consumption, and also frees a person from constant control of the temperature in the room. The set heating rate will be kept within the error set by the manufacturer of the device.
However, installer errors will cause a huge deviation in performance due to the following factors:
- The sensitive sensor capsule must be in a horizontal position. It is recommended to install the device at the base of the radiator. If this cannot be avoided due to pipe routing, then the following conditions are taken into account.
- The sensor capsule must be open. Curtains, furniture, decorative grilles, and close proximity to wall coverings interfere with the correct operation of the sensing element.
- If the location will inevitably be in a niche, then a thermal head for a radiator with a remote sensor is used here. The sensing element is located directly on the wall in the room, but not above the radiator. Avoid drafty places where cold air often moves from windows and doors.
- It is not recommended to cover the thermal head with curtains, and also to install the sensitive element vertically when the device is used horizontally.
Inaccuracies are introduced by installing a radiator and a sensor directly under a wide window sill, which traps heated air and distorts the measurement results. In the packaging of most devices, there is a product passport, but not all the conditions for the correct location are indicated there. Only experienced installers are able to accurately take into account even such a minor nuance for the layman as a draft due to an open window.
How does the system work?
The sensor device can be schematically represented as a regular valve or tap with a thermal head for a radiator. ATin contact with hot liquid is a thermostatic valve, in its simplest form, which is a spring with a piston. The elastic element is connected to the working volume, which contains a gaseous substance sensitive to temperature.
The pressing force is adjusted by the rotary scale knob, so the required temperature in the room is set. Depending on it, a piston moves, blocking the flow of fluid. The device is mounted with union nuts, this allows you to change the element when parts of its design fail. They provide additional fluid supply through ball valves in case of breakdown of the automatic control system.
What determines the heat transfer of radiators?
The type of connection of heating pipes affects the efficiency of the entire system as a whole. According to the reviews of installation specialists, the “bottom-down” radiator connection scheme is optimal. Such designs have an optimal loss of heat transfer coefficient and a minimum number of connections.
One-way or series connection of radiators is less efficient. The last element in the circuit practically does not heat, and the first one heats the room to uncomfortable temperatures. A versatile method of supplying pipes is found in private homes with enviable popularity, with this type there is an entrance on one side, and a liquid outlet on the other.
In the latter case, heat transfer losses will be 12%. The versatile method is optimal from the point of view of power distribution, but in the designrequires a lot of space and number of connections. The thermal heads themselves are divided according to the installation method:
- Angular - needed in parallel connection systems and with horizontal supply.
- Straight - used for sequential pipe laying.
You can use any connection scheme, only before work it is recommended to take into account the nuances of mounting radiators and thermal heads.
Features of the sensing element
Thermoheads for radiators with a bottom connection are needed when using a heating system in private homes. One-story buildings do not tolerate unnecessary communications, so the pipes to the radiator are brought from the floor. With this arrangement of the sensitive sensor, additional positive points appear:
- Cold air is at the bottom and is controlled by the coldest point in the room.
- The most accurate regulation occurs when thermal heads are installed for each individual supply. But such measures are more costly.
- More accurate temperature measurements are obtained when connecting radiators with separate parallel branches. A bypass pipeline passes through each, and the connection to the inlets takes place at a height of no more than 5 cm. This ensures high efficiency of the heating devices.
Types of producers
The leading brands in heating systems are:
- Kermi panel radiators (Germany) are equipped with Oventrop thermal heads;
- bimetallic Rifar (Russia);
- tubular Zehnder (Germany);
- steel panel Prado (Russia).
Kermi radiators are popular: therm-x2 plan-v typ11 smooth, therm-x2 profil-v profile. It is found in markings: FTV, PLV - with bottom eyeliner; FKO, PLK - from the side; Ph O - hygienic.
Types of shut-off and control equipment for radiators:
- "Oventrop" - manufacturer Germany: multiflex CE series for one-pipe systems; ZB series for two-pipe; ZBU customizable; F - composed of brass and soft seal. Oventrop uni with integrated valve.
- Danfoss - the following types: RA5062, RA5065, RA2920, RA2940, RA2994, RA5068, RA5074. They differ structurally and are designed for a certain radiator power.
Each manufacturer produces competitive models that differ in cost and principle of operation. Consider two types of thermal heads for radiators: Danfoss and Oventrop.
The first type of heating regulators
Oventrop is a thermal head for the Kermi radiator, and pipes are also produced under this brand. The manufacturing plant completes its products with shutoff valves of this type only. Plastic pipes "Oventrop" have an EVON coating, which is a protection against the harmful effects of oxygen.
Thermoheads "Oventrop" for radiators have been tested in production. Liquid regulators allow you to create an optimal heating control system, reduce resource consumption andmaintain the required temperature with a given accuracy. They were installed in Kermi radiators.
Second type of heating regulators
Thermal heads for Danfoss radiators can be made in the following variations:
- RTD-G - more throughput, larger connection diameter. They are used in a single-pipe heating scheme or in private homes when a two-pipe system is not equipped with a circulation pump.
- RTD-N - a two-wire connection to the radiators, a circulation pump is present.
For Danfoss RA2920, RA2940, RA2994 models, select only the horizontal placement of the regulator. Take into account the points that introduce measurement errors if the devices are incorrectly installed on the radiators. Convection currents should be considered when choosing a vertical sensing element.
Danfoss RA5062, RA5065 models have a long capillary tube, this design reduces measurement errors at any location of thermal heads. Types RA5068 or RA5074 are used in inaccessible areas and have a remote temperature sensor.
Knob selection options
The first point when choosing shut-off and control equipment is the type of heating system: one-sided, versatile, "bottom-down". The second are the dimensions of the sensor and valve design, throughput, temperature range. Of no small importance is the type of sensing element: gas, liquid, solid.
Gas filling is more sensitive to changesambient temperature. However, accuracy is lost. Liquid thermal heads change the flow when the value fluctuates by a fraction of a degree. The mounting method and location of the sensor, the option for displaying information is selected.
There are models with remote control, with LCD screen when running on batteries. Because of their practicality, the simplest designs with a built-in sensor have become widespread.
Installation Method
Remote control is required when mounting radiators inside housings, under grilles, in a niche. Installation of thermal heads begins with the emptying of the heating system. Before draining, it is recommended to cool the radiator so as not to burn yourself. The construction materials of the thermal head are quite soft and it is not recommended to overtighten the fastening nuts.
It would be better to use a torque wrench. There is a flow direction indicator on the body of the device; for proper operation, it is better not to confuse it. After assembling the sensor, the optimum temperature is set and proceed to start the liquid into the system.
It is recommended to bleed air from pipes and radiator. To do this, there is a drain valve that is unscrewed and part of the liquid is drained into a special container until the bubbles stop coming out.
Additional activities and maintenance of regulators
The selected temperature on the sensor is maintained automatically. The heating system requires annual maintenance after the cold season and before the onset of winter. Fluid often spoils without the use of filterscoarse cleaning and when tap water is used as the working medium.
Rust inevitably appears due to low-quality parts of the heating boiler, pump, valves. Solid impurities appear from the boiling of the liquid. During operation, it is recommended to periodically check the heating of each radiator by touch.
