Design and installation of water supply and heating systems for a house made of copper pipes

Recommendation points

• Normative documents for the development of the project and the distribution of water supply and heating from copper pipes
• Safety measures and restrictions on use
• Basic water supply and heating schemes from copper pipes
• Water supply: diagrams and wiring
• Heating from copper pipes
• Tools and piping installation
• Tools and materials
• Methods for connecting copper pipes
• Soldering
• Crimp

Copper pipes have unique performance properties and are still the best option for laying internal communications in the house. In this material, we will consider the principles and rules for installing a water supply system and a heating system made of copper pipes in order to use such an expensive material with maximum efficiency.

If the construction estimate allows the use of copper pipes, then this will be the best option for water supply and, especially, for heating. Their advantages include:

• resistance to sudden temperature changes, to possible freezing of water in pipes;
• easily tolerate high network pressure and even water hammer;
• resistance to chlorine in water;
• low roughness – minimal hydraulic resistance and reduced formation of lime deposits;
• bacteriostatic – bacteria do not grow in copper pipes;
• high aesthetics of external wiring.

Normative documents for the development of the project and the distribution of water supply and heating from copper pipes

In addition to the basic state standards for the design and installation of heating and water supply systems, specialized regulatory documents have been developed on the performance of work from copper pipes:

• SP 40-108-2004;
• STO NP “AVOK” 6.3.1-2007.

In the documents, you can find requirements for the chemical composition and assortment of pipes, for the composition of water, recommendations, tables and nomograms for hydraulic calculation, calculation of expansion joints and fasteners, requirements for connections and installation, compositions of solders, recommendations for corrosion protection, hydraulic test modes, repair recommendations.

Copper pipes intended for the distribution of heating and water supply must be manufactured in accordance with GOST R 52318-2005.

Safety measures and restrictions on use

As a safety measure against stray currents (copper is an excellent conductor) and external corrosion with hidden installation, it is advisable to use copper pipes in a protective polymer sheath.

The use of lead solders in the drinking pipeline is prohibited, since lead is a toxic substance. When connecting pipelines by soldering using fluxes, before using water for food, you need to flush the system using the “first” water for household purposes.

When connecting copper piping to aluminum equipment, in order to avoid the creation of a galvanic pair and, as a result, electrochemical corrosion, it is advisable to separate them with a dielectric insert – for example, a polypropylene fitting. Brass, bronze or stainless steel fittings are also acceptable. It is advisable to use radiators and mixers made of copper, bimetallic, as well as products that have already been prepared by the manufacturer for installation with a copper pipeline.

When using steel and copper elements in one system, it is advisable to install steel elements earlier in the water flow: for example, a riser is steel, wiring is copper. If this is not possible, it is necessary to use magnesium spacer products – passive anodes (used mainly in industry). To a greater extent, this applies to galvanized steel.

The activity of the reaction between metals depends on the concentration of oxygen in the water: the more oxygen, the faster the reaction rate. If the water supply of the house is autonomous, and there is aeration in the water treatment system (for deferrization), this should be taken into account when completing the pipelines. Also, unnecessarily, you should not drain all the water from the systems – this will reduce their service life..

Table. Galvanic compatibility: “+” – it is possible, “-” – it is impossible, “P” – connection is allowed only through soldering

Metal	Steel	Aluminum	Duralumin	Copper	Brass	Bronze	Chromium	Nickel	Zinc	Tin	Solder PIC
Steel	+	+	+	–	–	–	+	+	+	+	+
Aluminum	+	+	+	–	–	–	+	–	+	P	P
Duralumin	+	+	+	–	–	–	+	–	+	P	P
Copper	–	–	–	+	+	+	+	+	–	P	P
Brass	–	–	–	+	+	+	+	+	–	P	P
Bronze	–	–	–	+	+	+	+	+	–	P	P
Chromium	+	+	+	+	+	+	+	+	+	P	P
Nickel	+	–	–	+	+	+	+	+	+	P	P
Zinc	+	+	+	–	–	–	+	+	+	+	+
Tin	+	P	P	P	P	P	P	P	+	+	+
Solder PIC	+	P	P	P	P	P	P	P	+	+	+

Basic water supply and heating schemes from copper pipes

The diagrams for pipelines made of various materials differ slightly. Consider the main contours of the systems, taking into account the characteristics of the material used.

Water supply: diagrams and wiring

The pressure head and storage water supply systems are fundamentally different. The choice of system depends on the source (mainline or autonomous), average daily and peak flow rates, and the characteristics of plumbing equipment. The storage system is characterized by the presence of a storage tank installed at the highest point of the system: the higher the tank, the more pressure it can create.

Options for organizing water supply to a private house. 1. Well together with a pumping station. 2. Well and external pressure tower. 3. Centralized water supply. 4. Well and internal accumulator (free-flow diagram)

If the hot water supply in the house is centralized, the wiring around the house can be one- and two-pipe. With both schemes, in contrast to a dead-end cold water supply system, the water is constantly in motion, providing a sufficient temperature at any time of the day.

In the absence of a main supply, hot water supply to the house is organized using a storage or instantaneous water heater, autonomous – electric, or indirect heating – built into the boiler circuit.

Below are some typical hot water supply schemes.

Organization of hot water supply. 1. Two-pipe. 2. One-pipe with recirculation

By the type of wiring, a tee (serial) and collector (parallel) system is distinguished. The tee system is characterized by a low (relatively) cost and simple installation, but it is only suitable for houses with a small number of water intake points. In addition, if one mixer fails, the water will have to be shut off throughout the house..

1. Tee wiring. 2. Collector wiring (star)

The collector (beam) system is more complicated and more expensive, but it is ideal for a large house, without complicating anyone during operation:

• such a scheme ensures stable water pressure and temperature, regardless of the number of taps turned on simultaneously;
• any of the mixers can be turned off autonomously;
• the system is available for mounting new “beams” if necessary;
• adjustment of the entire system is concentrated in one place: on the collector.

The collector circuit is more material intensive, which, given the cost of copper pipes, matters.

Below are examples of the distribution of cold and hot water according to the collector circuit for two bathrooms and a kitchen.

Heating from copper pipes

As with the use of other materials, heating assembled from copper pipes can be gravity and forced. The gravity system is arranged in one-, two-story houses, works due to the forces of gravity, changes in the density of the coolant during heating and cooling. For normal operation of a system with natural circulation, pipes of the largest possible diameter are selected to reduce hydrodynamic resistance.

Heating with natural circulation. 1. Boiler. 2. Expansion tank. 3. Heating radiators

The forced system includes a pump that pumps the coolant through the pipes, creating excess pressure and head. Pipes can be selected with a smaller diameter and to compensate for the increased resistance due to the high head of the circulation pump. Considering the cost of copper, the second option seems to be more attractive in terms of overall costs.

Forced circulation heating. A. One-pipe wiring. B. Two-pipe wiring. 1. Boiler. 2. Security group. 3. Expansion tank of membrane type. 4. Circulation pump. 5. Radiator

By the type of wiring, one and two-pipe systems are fundamentally distinguished, each of which has its own design options.

The greatest advantage of copper pipes over metal-plastic ones, which are now widespread, is manifested in single-pipe wiring. Copper makes it possible to sequentially mount a long chain of radiators: more than 5-10 pieces. The coolant, if desired, can be heated to the permitted 150 ° C, therefore, even in the last, in the direction of travel, the water temperature will be high enough, maintaining the proper power of the body return.

The two-pipe scheme can be: passing (Tichelman loop), dead-end (shoulder) or beam (collector). There is no unambiguous leader among the systems, it is necessary to consider the application of this or that scheme individually, although in most cases builders prefer a passing scheme.

1. Tichelman loop. 2. Dead-end or shoulder wiring

Collector heating wiring

When installing underfloor heating, copper pipes provide good temperature uniformity, are very reliable, durable and can be laid without fittings, exclusively by bending according to one of the following schemes:

• spiral;
• snake;
• double snake.

Double snake gives the best temperature uniformity over the heated area.

1. Snake. 2. Double snake. 3. Double helix

To supply underfloor heating, a separate boiler circuit can be allocated, or the wiring is installed on the return pipe at a low temperature of the coolant.

Advice! When installing underfloor heating, apply the screed only after testing.

Tools and piping installation

After the development of the project, you need to prepare the necessary tools and materials, carry out installation in accordance with regulatory documents and conduct hydraulic testing.

Tools and materials

Many well-known companies produce specialized tools and fittings for installing copper pipes.

The most famous are:

• REMS, Germany;
• Viega, Germany;
• Rothenberger, Germany;
• Virax, France.

To cut the measured sections of the pipeline, you will need a pipe cutter (for thin-walled products) or a hacksaw for metal (for thick-walled products). The calibrator is designed for deburring and enlarging the diameter of a thin-walled pipe for fittings. In some cases, a reamer and flare tool will be required instead of a calibrator. To bend pipes, you will need a pipe bender – spring, crossbow or other design, which gently bends thin-walled sections of copper pipeline.

1. Manual pipe bender with electric drive. 2. Hydraulic manual pipe bender. 3. Spiral for bending copper pipes

For different types of connections, you may need:

• a torch with a cylinder and a flux brush for soldering;
• crimp connection pliers.

Advice! Choose burners with piezo ignition – a very convenient function.

There is a special tool for copper pipes – a beveler. With its help, bends are formed from the material of the pipe itself, which reduces the cost of fittings.

You may also need wrenches (especially for threaded connections), a file, fine sandpaper, or a polymer rough scrubber.

The materials required depend on the type of connection:

• fittings – for soldering, crimping, threaded connection;
• solder and flux for soldering;
• fum tape for threaded connections.

Methods for connecting copper pipes

Solder and crimp connections are available for thin wall pipes. Thick-walled ones are mounted using compression and threaded fittings, as well as flange connections (for large diameters, they are rarely used in private houses). Copper can also be welded, but this method is only available to professionals, so it will not be considered further.

Soldering

For the installation of engineering in-house systems, it is sufficient to perform soft soldering at temperatures up to 250 ° C. Soldering with hard solder, although it forms a stronger connection, is performed at temperatures up to 730 ° C, requires more expensive tools, solder and higher qualifications of the craftsman. This type of connection is required for refrigeration and climatic technology, where significant working pressure is created inside the pipeline..

Special copper fittings are needed to solder the pipeline. It is also possible to reduce the number of fittings for soldering due to the formation of bends from the material of the pipe itself..

Below is a diagram of creating a bend on a copper pipe using the extrusion method without using a tee..

A hole with a diameter of 2 · 3s less than the diameter of the inlet pipe is cut in the pipe, where s is the wall thickness. The working rod of the bell is inserted into the hole, and then the drive is turned on and the side pipe is removed. This method only works fine for soft copper pipes. If necessary, solid pipes are pre-annealed in the place where the bend is formed.

Copper tubes are connected by capillary soldering (term according to GOST 17325-79). To make a soft solder connection:

1. Prepare the pipe for brazing – remove burrs, the oxide film from the inside with a metal brush, and the outside surface with a soft sandpaper.
2. Apply flux to the outer surface with a brush to evenly distribute the solder.
3. Insert the pipe into the fitting. The annular gap should be less than 0.5mm.
4. Use a gas torch (or blowtorch) to warm up the joint without holding the flame in one area.
5. As soon as the solder starts to melt when it touches the heated area, the desired temperature is reached.
6. Solder by injecting solder into the annular gap. The flux must ensure uniform spreading.
7. Leave the joint at rest until completely cooled, then strip the seam.

Crimp

It is somewhat easier than soldering to make crimp connections. This requires press fittings with an inlay to ensure the tightness of the pipeline. The pipe is inserted into a press fitting with a tab, after which it is clamped with pressing tongs with a force of 32 kN, forming one or two compression circuits. There are also fittings using special sleeves with double O-rings for soft copper pipelines. Different manufacturers use different methods of visual control of the crimp performance: these can be edges crumpled into a comb, a broken plastic ring, etc..

For thick-walled pipes, it is rational to use compression or threaded fittings. When connecting thin-walled pipe sections to thick-walled pipelines, there are transition fittings.

Finally, watch a video on how to solder and crimp.