The Internet contains a lot of different information on the design of engineering systems.

So as not to repeat the already written, we briefly review the features of the design of heating, and in particular, PEX underfloor heating and cooling surfaces.

Also, pay special attention to some points, if ignored, may result in numerous waste, rework and make the construction process chaotic.

There are statistics on the cost of construction work. According to them, building a house without a project cost on average 15% more expensive and 20% longer than the construction of the project. This despite the fact that the project is worth about 5% of the value of the house, and it takes full account of all the needs of the customer.

Plus, at times reduced confusion and conflict on the site.

When selecting and installing materials and equipment without the project is likely that the cash investments of the customer several times higher than really necessary. On the other hand, in an effort to minimize the cost of the equipment can be selected, whose characteristics can not provide the solution of tasks.

Of technological literacy project depends on the level of financial costs, not only for the installation of heating systems, and the continued operation and maintenance. The proper selection of equipment depend on its safety, durability, functionality and appearance. So do not hesitate to ask your designer - and literacy in depth answers, you will be able to judge the level of their competence, and not be tormented by doubts superfluous.

1. Providing customer input to project development. At this stage it is necessary to treat with the utmost seriousness. Errors and omissions in this stage do further work on the project will be meaningless. At a cost of filling the questionnaire 30 minutes - you will save thousands of dollars that could be used to address the results of errors caused by incomplete or incorrect input data. Source data must be complete and accurate as possible.

2. Thermal envelope calculation. All complex construction

calculations, including Thermal, produced in specialized computer programs Thermal calculation. For existing buildings is calculated heat transfer coefficient of the building envelope K [W / (m2 × ° C)], based on the original data. Also commonly used reciprocal of the coefficient - thermal resistance R [(m2 × ° C) / W]. If a building is only designed, based on the results of heating may be deduced about the properties of energy-saving design of structures, and the appropriateness of their additional warming. Or at a rate of heat transfer resistance can appreciate how "warm" your walls and windows. The higher the thermal resistance of the construction R, so it keeps the heat of the room.

Resistance values are normalized by state building codes.Examples of the calculation of the exterior walls of structures are given in the table below:Name Construction fences, thickness

Thermal resistance, [W / (m2 × ° C)]Normative value for Kiev Calculation temperature graphOutdoor Ceramic brick wall 1 40 cm 0.86 2.8 Thermal calculation bricks 40 cmOutdoor Ceramic brick wall 2 40 cm + 10 cm foam 2.85 2.8 Thermal calculation bricks 40 cm and plasticRoofing Drywall 1 min wool 10 cm, wooden crate 2.36 4.95 Thermal calculation roof mineral wool 10 cmRoofing Drywall 2 min. wool 20 cm, wooden crate 4.29 4.95

Thermal calculation of roof mineral wool 20 cm

Not estimate the heat loss area in square meters!

Often heat loss areas are commonly calculated by the specific heat load, for example: 100 W / m ² floor area multiplied by 100 m ² and get heat loss 10 000 W = 10 kW. This methodology is valid only to a certain extent for a preliminary determination of the total heat load of the building as a whole and is indicative. When the average unit heat loss through the building 100 W unit heat loss areas can vary widely from 20 to 200 W / m ² or more.

Example of calculation of heat loss of three buildings in the same area of Aurora, IL. Heat loss from the same premises have 25, 87 and 220 W/m2!

Therefore, to determine the heat loss from individual buildings to the following factors:

- Heat transfer coefficients walling;- Square envelope;- Outdoor temperature. For Illinois home, for example, take the minus 22

degrees;- Room temperature;- The presence or absence of mechanical ventilation;- Ventilation rate and supply air temperature,- Availability of additional sources of heat or cold in the room.

Example - payment in full heat for a residential home in Rockford, IL.

Development of preliminary layouts zones underfloor heating heating zone valves, PEX tubing with Oxygen barrier, circulator pumps and radiant heating manifolds. We strongly recommend you for use PexMall.Com – this store has best rates in internet for any radiant floor heating supplies.

Pexmall, LLC

40 E. Main St., #1098

Newark, Delaware 19711

http://www.pexmall.com/radiant-floor-heating

Based on the calculated heat loss, room configuration and customer plans are put on the floor area where it will be mounted Radiant floor.

The advantage of water underfloor heating is that it gives you the freedom to design solutions for furniture arrangement, in contrast to the electric floor heating. The pipe can be laid even under furniture.

As practice shows, on average, under standard conditions warm floor can cover load of about 100 W / m ². This may vary in the smaller or increase depending on:

- Pitch PEX pipe is laid in a loop

- Diameter of the PEX pipe;

- The temperature of the coolant into and out of the water circuit floor heating;

- Floor covering;

- Insulation for PEX pipe;

- Thickness and material ties;

- The internal temperature in the room - for example, in a private home country 22 ... 24 degrees, and in the storage room - 12 degrees.

The maximum possible heat transfer is limited, typically:

- Permissible temperature of the floor surface to the building regulations;

- The maximum permissible temperature screeds and floor covering, on the recommendations of their manufacturers.

Limit temperature heating surfaces in accordance with building standards and regulations in force in Ukraine, snip 2-04-05-91 * are:

+26 ° C for floor space with the constant presence of people;

+30 ° C to bypass lanes, benches, swimming pools;

+31 ° C for floor space with a temporary stay of people and boundary zones;

+28 ° C, +30 ° C, +33 ° C, +36 ° C, +38 ° C for heating the ceiling height of the room does not exceed 2.8, 3.0, 3.5, 4, and 6 m, respectively.

warm wall beneath window rooms with large heat losses if floor heating can not cover them, to install additional heating devices designed or wall heating.

Often, too, the power is not enough floor heating in the bathrooms. Desired temperature in the bathrooms private home country relatively high +24 ° C, and the effective area of floor heating is not enough. If the bathroom has a window, you can set them under additional heater or warm wall, which in addition to its main task - air heating, will also neutralize unpleasant convective movement of cold air descending from the window down, and prevent condensation on the glass. If there is no window in the bathroom or the placement of Engineers has not determined under the window heater, uncovered balance of power should be covered by the wall heating or heated towel rail.

For the installation of risers should be sufficient space in the channels of the walls. Best of all, when the risers heating system distribution manifold located at the geometric center of the zone underfloor heating. Often this center coincides with the center of the ground floor of the building. This placement makes the length of pipe from the distributor to the contour of the floor heating the same, which in turn facilitates the hydraulic system setup and make it work stable.

To avoid expensive works on wall space for installation of risers shall be provided at the stage of architectural design or construction of the building.

Typically, at this point a few times have to change the configuration of the proposed system underfloor heating depending on the wishes of the customer. Follow the detailed calculations made after appropriate agreement on basic policy decisions, schemes with the customer and make any necessary changes.

The detailed design drawings, thermal and hydraulic heating design of the floor PEX system.

After agreeing to be the preliminary schemes detailed calculation of the project.

Calculated and shown on the drawings:

- The final contours of water capacity of floor and wall heating,- Power, models and sizes of floor heating supplies;- Pitch PEX tubing laying;- Diameter PEX tubing;- The characteristics of the distribution of reservoirs;- Valves and the values of its settings (valves, control valves for

hydraulic adjustment and alignment of circuits);- The design of the "pie" warm floor.

The problem of heating calculation - to choose the system configuration and materials, structural analysis of gender, circuits and heaters so as to provide the required comfort conditions in the room.

The problem of hydraulic calculation of water underfloor heating - to make the system stable and to obtain data for the sizing of pumps and boilers.

Example drawing of heating warehouse and trading center.