Quick one-man installation of a house gas pipeline

Can one man alone efficiently install a domestic gas pipeline at a family house?

Most gas fitters have to build a home gas pipeline with a rather complicated process of welding PE pipes in a hard to reach trench, thorough insulation of this joint and many other various tasks. That’s why they need at least two installers for a project of this type.

There is, however, a solution that can cut the installation time in half and, what’s more, it can easily be done by a single worker! This highly efficient solution is because of the MERABELL GAS PROFI piping system.

An illustrative example will be shown here by the company VTP Štěpánek from Havířov, which usually uses bellows pipes made of stainless steel when connecting boilers. Recently, they have also discovered the “yellow” MERABELL GAS PROFI pipe, with which it is possible to install not only the internal gas distribution, but a complete gas connection from the main pipeline in the ground to the interior of the house in one piece without a joint. Another implementation of MERABELL GAS PROFI pipeline by VTP Štěpánek was a wooden house in the picturesque village of Čechy pod Kosířem in Haná region. The construction took place in typical April weather. Therefore, the installation had to be done very quickly while the weather was favourable. This is an ideal case for the use of MERABELL GAS PROFI pipe.

What are the advantages of using the “yellow” MERABELL GAS PROFI pipe?

Speed of installation - the correct construction of a domestic gas pipeline from conventional materials (PE pipe with a transition to copper) requires many different tasks such as welding, pressing, insulating, laying the signal wire, etc. The vast majority of these tasks are completely eliminated with flexible stainless steel pipe, as the pipeline is made of one piece and the necessary pipe bends are easily formed by hand. The assembly time is thus much shorter.
One man is all it takes - the entire installation can be easily handled by one trained gas fitter alone. He only needs a few minutes of minor assistance in threading the pipe into the casing and pulling the pipe through the building structure. Here, even completely unqualified persons present on the construction site, such as the owner of the building, the driver, or another craftsman, can be used.
100% safety - with stainless steel pipe, the pipeline can be constructed with a minimum of joints. This eliminates the risk of potential leaks in the joints. The connections are only at the beginning by the main pipeline, and at the end by the boiler. The joining is done by crimping the end of the pipe with a lever press.
One pipe for everything - usually a gas pipeline is built from two systems (exterior and interior) and a minimum of one safety valve needs to be installed. With the MERABELL GAS PROFI pipe, the entire distribution system is built from one system from the main pipeline to the boiler inside the house. This eliminates the need for any additional safety features.
Smart tools – hand lever press by MERABELL is significantly cheaper and easier to operate than copper press tools. In addition, these must be calibrated regularly, which costs additional money and especially the time when tools are not available for work.
Superior warranty - stainless steel is a high quality and non-flammable material. MERABELL GAS PROFI products are therefore covered by a superior 10-year warranty.

Technical design

The required pipe dimension DN25 / 5/4” was selected using on-line pipe calculator www.merabell.com/calculator. A 30m coil of yellow MERABELL GAS PROFI pipe with a diameter of DN25/5/4” (M00129) was selected.

The piping runs from the main gas shut-off valve at the plot boundary to the technical room in the basement of the family house, where the gas boiler will be located. The exterior pipe was placed in a trench under the ground and the interior pipe under the floor. The pipe was placed in a yellow sleeve with an outer diameter of 50 mm. A steel protection pipe was used for the transition through the supporting structure of the house. After removing the protective sheathing (we recommend knife M0304), the ends of the pipe were cut with cutter M0305 and crimped with lever press M0303. The exposed ends behind the nut were re-insulated with M0321 vulcanizing tape. The total length of the entire gas pipeline from the main shut-off valve to the boiler is 19 metres. With the MERABELL GAS PROFI pipe, the gas pipeline was installed without a single joint. There was no need to use any safety valve.

Main benefits of GAS PROFI pipes

pipe is made of high quality stainless steel AISI316L
flexibility of the pipe allows shaping by hand
is covered with yellow protective PE (polyethylene) sheathing.
The MERABELL GAS PROFI pipe is certified in accordance with the ČSN EN 15266 standard, which allows the pipe to be routed in the wall without a protection tube. Protection tube must be used when passing through the perimeter wall, underground and under the floor.

Main benefits of GAS PROFI hose with gas lock and thermal fuse

The MERABELL GAS PROFI hose is certified according to the ČSN EN 15266 standard (Stainless-steel pliable corrugated tubing kits in buildings for gas with an operating pressure of up to 0.5 bar) that is already mandatory in the Europe. The hose is protected against mechanical damage on its surface by a clear PVC protective jacket and a stainless-steel braid. The swivel ending on the side of appliance (cooker) prevents the hose from twisting in the thread and possible gas leakage. The thermal fuse of the valve automatically closes the gas supply when the temperature exceeds 100 °C. The bayonet lock allows for very easy disconnection and connection of the gas appliance by the user, without the need to call a certified installer – e. g. when it is necessary for painting, cleaning.

The main benefit of this premium hose lies in a unique 25-year warranty, which allows its long-term use without the need for replacement after regular inspections or when replacing the appliance. In the long run, this abundantly compensates Heimstaden for the higher purchase price of the hose, which is only in the order of hundreds of crowns compared to the solution used so far (conventional gas hose + VAIT safety valve).

Excerpt from standards and technical regulations

Source TPG 70401:
It is necessary to use stainless-steel pipes according to EN15266 for the construction, repairs and extension of house gas pipelines.

Source EN 1775:
Article 5.2.5 prescribes that joints made of stainless steel-flexible pipes may only be made by persons with special training and reference is made to informative Annex E for instructions on how to join this type of pipes. *You can sign up for certification training here:

Part E2: Only a pipe and fitting system that meets the requirements of EN 15266 should be used.

Gas distribution systems consisting of stainless-steel flexible pipes run underground:
When installed below ground level, the pipes must be placed in a protector, one end of which is led out into the space (cabinet, niche, etc.) so that a gas leak can be checked. A sufficient solution is to lead out one end of the protector, with the other side being designed as a sealed end. The unsealed end of the protector must be secured against water ingress, e.g. in case of rain, etc.

The depth of the pipe installation below ground level must be at least 600 mm. If the minimum installation depth of 600 mm below ground level cannot be observed, the pipework must be mechanically protected against any impermissible loads, e. g. by a protective pipe.

Recommended installation procedure

prepare excavation with minimal depth of 80 cm and fill it with sand
insert the protective pipe into the passage through the peripheral masonry (for DN 5, min. inner diameter should be 40 mm)
measure the length of the piping from the main gas shut-off valve up to the appliance (including internal pipeline)
prepare the protector for underground part of the distribution system
prior to laying into the trench, slide the protector onto the pipe in a free space (be careful not to damage the PE jacket by careless handling, contact with coarse and sharp objects)
place the pipe with the protector in the trench and pass it through the wall into the building
thread a nut on the piping, crimp the end of the piping, fit the gasket and install into the cabinet with main gas shut-off valve
make a backfill up to the height of 30 cm and lay a warning film
fill up to ground level

Project assessment

Thanks to the efficiency of the MERABELL GAS PROFI system, VTP Štěpánek managed to build the entire home gas system from the main pipeline to the appliance in couple of hours.

When comparing the costs, it turned out that even a higher purchase price per meter of stainless-steel piping does not necessarily mean higher total costs. In this particular case, the price for 3,5 hours of work, 21 m of MERABELL GAS PROFI piping, protector and two nuts was even a few hundred crowns cheaper than the original budget for the combination of PE and copper, where a significantly larger number of transition and connecting elements would be needed. Thanks to the significantly reduced installation time, the MERABELL GAS PROFI pipeline is clearly a more efficient solution.