For residents of apartment buildings, especially old buildings, from year to year, with the onset of the cold period, the same problem arises. We are talking about the quality of heating residential premises. Centralized heat supply, despite all its archaism, remains today the main option for heating the housing stock in almost all settlements and cities of our country.
For reference: According to the State Statistics Committee, today up to 75% of the housing stock in our cities is heated by a centralized heating system.
Hot batteries in the house are not yet a sign that it will be warm and comfortable inside the apartment. Autonomous heating, underfloor heating in the apartment, heating methods that most of our citizens can only dream of. Apartment buildings, especially «Khrushchev» and panel high-rise buildings, due to their design features, are characterized by huge heat losses. Normally warming up a residential building with conventional radiators in severe frosts is a problematic task.
For this reason and for a number of others, residents are forced to look for ways to help solve the problem. One of the effective, relatively inexpensive and most practical options for additional heating is a heated floor from a heated towel rail.
Connecting a heated floor to a heated towel rail
The idea of using centralized heating as the main source of heat for the operation of other heating systems in the apartment is not new. Using massively electric household heaters to create a comfortable temperature in an apartment is a costly exercise. Insufficient thermal efficiency of residential premises causes high costs for additional heating. Underfloor heating in this regard is the most effective way of heating. For private houses, this heating scheme is real and feasible, but for city apartments, the legality of this engineering and technological solution comes first.
The main reason for the ban is that inserting additional heaters into the central heating system can adversely affect the quality of heating in neighboring apartments.
For reference: in a central heating system, the working pressure differs significantly from the optimal parameters that the pipes of the underfloor heating circuit have. Do not forget about the temperature of the coolant. For a warm floor, the optimum heating temperature is 35-450C, while in the radiators of the central heating system the coolant has a temperature of 65-750FROM.
The incompatibility of operating parameters calls into question the combination of a centralized heat supply system with a heating pipe laid in the floor. If we omit the legality of this engineering solution in this situation, heating engineers speak negatively about the idea of using a heating plant for underfloor heating. The poor quality of the coolant and the high probability of water hammer makes such a technical solution a problem area in the apartment. It’s a completely different matter when it comes to heating a limited area in your apartment.
For example: a bathroom, toilet and other rooms are in dire need of additional heating. Install a heated floor in the bathroom, which will be connected to a heated towel rail, a task that you can handle on your own. Calculations and expenses in this case do not play a key role. A small area and small amounts of work allow this heating method to be used in a city apartment without harming neighbors.
Principles of operation of the heating system
Such a connection option does not represent technical complexity. The heated towel rail is a heating device installed in almost every city apartment. From a constructive point of view, this is an external communication element through which the hot coolant or hot water of the DHW system circulates. Such elements are often placed as a compensating loop of the heating system, playing the role of an additional source of heat in rooms with high humidity. The name of the element speaks for itself, hence the serpentine shape, thanks to which the heated circuit can be effectively used.
For aesthetics, towel warmers are usually made of stainless steel or plated with nickel. The very design and method of connecting the heated towel rail to centralized communication make it possible to connect a water floor pipe to it without much difficulty. As a rule, pipes of small diameter are used for underfloor heating. For a bathroom, the area of \u200b\u200bwhich rarely exceeds 4-5 m in a city apartment2it will take only 15-20 meters of pipe.
There are two types of heated towel rails:
- a coil that is connected to a centralized heating system;
- coil, which is connected to a centralized hot water supply.
In the first case, with the onset of the heating season, water fills the heated towel rail and, accordingly, enters the underfloor heating circuit, heating the floor surface.
The first option works only during the heating season. The rest of the time your warm floor will be inactive. A coil connected to the DHW system looks preferable. Such a floor in the bathroom will always work, providing a good microclimate and a comfortable temperature.
What does the wiring diagram look like?
The option of connecting a heated towel rail in an apartment also determines the method of installing a warm water floor.
On a note: in some houses, the coil installed in the bathroom is fed by the coolant going in the opposite direction. This option is the most suitable in terms of manufacturability.
The acceptable temperature of the coolant allows the floor heating to work with maximum efficiency. However, there is one thing! At the end of the heating season, your coil will be cold and no use will come from a warm floor. This wiring diagram is not ideal.
Underfloor heating works better when connected to a heated towel rail connected to the hot water supply of the bathroom. Here you need to select a pipe for the water circuit of the correct diameter, accurately calculate the length of the pipeline, the heated area and choose the correct connection method. It is better to take metal-plastic pipes for a warm floor, with a diameter of 16 mm.
The installation process itself is quite simple and straightforward. All work consists in connecting (insert) to the main pipe (riser) of the water floor circuit. The new pipe will go to the floor, and return back to the coil. Be sure to install a starting valve at the tie-in point, with which you can adjust the flow rate, turn on and off your additional heating. This option is the simplest and cheapest, but provided that the pressure in the pipes is within normal limits.
Underfloor heating, as usual, is not much different from traditional practice. The water circuit pipe is laid into the substrate with a certain step. The bending radius of the pipe should be minimal to ensure the normal flow of the coolant throughout the system. If you cannot do with one circuit in the bathroom, you will have to use a manifold. With this device, you can not only connect a larger number of water circuits, but also accurately regulate the water supply and the heating temperature of the heating floor. You can install a circulation pump for reliability, however, the profitability of your miniature heating system will be minimal.
Conclusion. What problems can you face
Using centralized heating and a hot water system for installing underfloor heating is a rare phenomenon and is rather an exception to the rule. The efficiency of your design directly depends on how centralized communication systems work. The pressure drop in the system, the deterioration of the quality of the coolant affects the permeability of the water circuit.
You should also be aware of possible emergencies. As a result of a rupture of the heating circuit pipe due to water hammer, the resulting leak will have to be eliminated immediately. To do this, you will need to remove not only the tiles, but also dismantle the screed section. It is highly likely that if the integrity of the water circuit is violated, you will flood your neighbors from below.
It should be remembered! A hot towel warmer will be a problem for you. The absence of a heating regulator in this case will become an obstacle for you to set a comfortable temperature in the bathroom. An overheated floor will dry out a small bathroom. Interruptions with hot water in apartment buildings are a fairly frequent phenomenon, so there is no reason to rely on the constant normal operation of a warm floor.
A collector and a temperature control sensor will help to partially solve the problems, but then your heating system will go beyond the planned budget.