Vaillant refrigerant pipe 5/8" (15.88 mm) - 25 m, insulated

Product detailed description

Vaillant refrigerant pipe 5/8" - 25 m, insulated

This insulated copper refrigerant pipe with a diameter of 5/8" (15.88 mm) and a length of 25 metres represents the largest combination of diameter and length in the range of Vaillant installation accessories for climaVAIR air conditioners. It is intended for more demanding installations that combine the need for a larger diameter (more powerful climaVAIR pro units with an output of 5.0-7.0 kW, or the main branch of multi-port outdoor units of the climaVAIR multi multisplit system) with the need for a longer run - for example in larger family houses, multi-storey buildings, or where the powerful outdoor unit is placed further away.

Thanks to the 25-metre length in a single package, you can usually avoid the need to join several pieces of pipe together even on more demanding runs. The pipe is factory-fitted with thermal insulation along its entire length, which prevents heat loss and condensation of air humidity on the surface - important especially on long runs passing through several heated or air-conditioned rooms.

Technical parameters

Which installations this diameter and length combination is intended for

The combination of the largest available diameter (5/8") with the longest package (25 m) is mainly used for: more powerful climaVAIR pro units with a longer run to the outdoor unit; multi-port climaVAIR multi multisplit systems, where the main branch from the outdoor unit to the first distribution point (refnet) carries the combined output of all connected indoor units over a longer run; or buildings with an unusual outdoor unit location (roof, distant utility room). Always check the exact prescribed combination of diameters and the maximum permitted lengths/height differences for the run in the installation manual of the specific units.

Installation principles when working with long, larger-diameter pipe

Cutting is done with a copper pipe cutter with sufficiently wide jaws for a 5/8" diameter. Given the combination of greater weight (due to the diameter) and greater package length (25 m), pay particular attention to safe handling of the whole coil when transporting it to the installation site and when gradually unwinding it - it is recommended to unwind it in smaller sections rather than all at once along its full length. Before charging with refrigerant, the circuit is purged with nitrogen, followed by a pressure test and evacuation to the prescribed vacuum level; these operations, as well as the actual refrigerant charging (usually the largest volume of the entire pipe range for this diameter and length combination), may only be carried out by a company authorised to work with F-gases.

When routing a long run of larger-diameter pipe, pay increased attention to denser fixing of the pipe along its entire length (shorter spacing between clips than for thinner diameters), so that the heavier pipe does not vibrate during compressor operation and place strain on the flare joints at both ends of the long run.

Frequently asked questions

Is this diameter and length combination suitable for an ordinary simple flat?

Usually not - this combination is intended for more powerful units and/or longer runs. For an ordinary flat with a short run, a thinner diameter or the shorter 10-metre package from our range will be sufficient.

Is the pipe insulated?

Yes, factory-insulated along its entire length.

Can the unused part of the pipe be used for another installation?

Yes, the excess part can simply be cut off and used for another, smaller installation or kept as a reserve.

Why is this package the most expensive in the pipe category?

It combines the largest diameter (most copper per metre) with the largest package length (25 m), making it the highest-priced variant within the refrigerant pipe range.

Storage and handling before installation

Until installation, keep both ends of the pipe sealed as delivered by the manufacturer. Due to the combination of larger diameter and length, this is the bulkiest and heaviest pipe package in the entire category - allow for adequate space and load capacity during transport and storage, store the pipe in a dry place, and protect the insulation from mechanical damage.

Why choose genuine Vaillant pipe

In more powerful and larger installations, for which this diameter and length combination is intended, correctly sizing the pipe has a particularly large impact on the overall performance and reliability of the system. Using pipe with the correct diameter, wall thickness, and insulation quality according to the manufacturer's specification is a prerequisite for maintaining the warranty on the air conditioning system as a whole.

Refnet distributors and the main branch in larger multisplit systems

For multi-port outdoor units that serve several indoor units simultaneously over a longer run, the main branch between the outdoor unit and the first refnet distributor is most often implemented precisely in a diameter of 5/8" or larger. For longer main branches (25 m), it is also important to observe the maximum permitted height difference between the outdoor unit and the furthest distributor, as stated by the manufacturer in the installation documentation for the specific multisplit system.

Leak testing and safety

After installation, all flare joints are checked for tightness using leak-detection foam spray or an electronic leak detector. With this combination of larger diameter and longer run, any refrigerant leak represents the relatively highest volumetric flow rate among the entire pipe range, so thorough leak testing after installation is extremely important.

Warranty and compatibility

The pipe is a supplementary installation material for Vaillant climaVAIR systems and is covered by the standard 2-year warranty period. Using pipe that matches the manufacturer's specification is a prerequisite for maintaining the warranty on the air conditioning unit as a whole.

Extended frequently asked questions

Can this pipe be used with other air conditioner brands too?

Yes, it is a standard ACR copper pipe with a common 5/8" diameter, compatible with other brands using the same gas branch diameter. Always check the prescribed diameter in the installation manual of the specific unit.

Is it worth ordering the full 25 m even if the exact run length is not completely certain?

Yes, if in doubt, it is safer to order a longer package with a margin - additionally buying and joining a second package means an extra joint on the most heavily loaded branch of the circuit.

Does the pipe need any preparation before installation?

No, it is delivered ready for installation - simply cut it to the required length, form the flare cones, and connect it to the units.

Material and processing of the copper pipe

This is high-purity ACR copper, degreased on the inside directly at the factory, supplied in soft (annealed) copper form. At this largest offered diameter, the pipe is significantly stiffer than thinner variants, so when shaping any bends along the run, it is strongly recommended to use a pipe bender of the appropriate diameter instead of manual shaping, which at this wall thickness risks visibly flattening the cross-section.

The effect of diameter and length on system performance and noise

On long runs with a larger diameter, it is important to precisely follow the prescribed amount of additional refrigerant charge based on the run length - insufficient refrigerant charging on a longer run of larger diameter results in a noticeable drop in performance, while excessive charging can overload the compressor. A correctly sized combination of diameter and refrigerant quantity for the given run length ensures quiet operation and full utilisation of the unit's declared output.

Which pipe diameter and length do I need

In this category you will find Vaillant refrigerant pipe in diameters of 1/4", 3/8", 1/2" and 5/8", in lengths of 10 m and 25 m. This largest combination (5/8", 25 m) is intended for more demanding installations - don't forget to also order the corresponding smaller-diameter liquid branch (typically 3/8" or 1/4" depending on the specific system), ideally also in the 25-metre length, so that both branches run alongside each other without the need for additional joints.

Delivery and transport

Due to the combination of the largest diameter and the longest package, this is the largest product in this accessory category in terms of both volume and weight - delivery is therefore usually carried out by courier directly to the address rather than to a parcel locker, as the size and weight of the package commonly exceed the limits of most pickup points.

Recyclability and environmental impact

Copper is a fully recyclable material. Due to the larger diameter, a metre of this pipe contains the most copper in the entire range, which, in the event of a replacement or shortening of the run, also represents the highest material value of the returned offcuts at a scrap metal collection point.

Summary - who this product is intended for

The 5/8" refrigerant pipe in a 25-metre package is intended primarily for installation companies carrying out more demanding installations - more powerful climaVAIR pro units on longer runs or larger climaVAIR multi multisplit systems with several connected indoor units. It is the most extensive (and highest-priced) diameter and length combination in this accessory category, so it is worth thoroughly checking the exact requirements of the specific unit combination in the manufacturer's installation manual before ordering, or consulting the choice with your air conditioning supplier.

Don't forget to also order the corresponding liquid branch for this pipe, and if needed, replacement or antibacterial filters for the indoor units - all accessories can be found together in the Vaillant Air Conditioning Accessories category.

Planning larger multisplit installations

When designing a larger multisplit installation with several indoor units connected to one powerful outdoor unit, it is advisable to first design the position of the refnet distributors so that the sum of the branch lengths to the individual indoor units does not exceed the maximum total pipe length prescribed by the manufacturer for the given system. The larger-diameter main branch (this product) should run as directly as possible to the first distribution point, from where the refrigerant is then distributed through thinner branches to the individual indoor units according to their individual output.

For such large installations, it is worth having the installation company or supplier prepare a precise run design, including the required diameters and lengths for each section, before ordering the material - this avoids additional purchases or, conversely, surplus material after the installation is completed.

Typical mistakes when installing large systems

In larger installations with longer runs of larger diameter, the most common mistake is underestimating the number and spacing of fixing elements along the entire length of the run - a heavier, larger-diameter pipe without sufficient fixing can sag over time, leading to uneven stress on the flare joints at both ends. Another common mistake in multi-port systems is incorrectly determining the diameter of one of the branches after the distributor - the manufacturer prescribes an exact diameter for each branch according to the output of the specific connected indoor unit, not a uniform diameter for all branches alike.

Pressure testing and evacuation procedure for a larger circuit volume

With the combination of larger diameter and longer run, the total internal volume of the refrigerant circuit is significantly larger than for shorter and thinner pipes in this category, which extends the time required to reach and maintain the prescribed deep vacuum level during the vacuum test. After connecting both pipe branches to the service valves, the circuit is first pressurised with nitrogen to the value prescribed by the manufacturer and left for several hours to check for tightness; the nitrogen is then released and the circuit is connected to a vacuum pump with sufficient capacity for the given circuit volume. Only after confirming that the vacuum holds at the prescribed level for a sufficient time are the service valves opened and the refrigerant released into the entire circuit.

Due to the larger circuit volume, it is particularly important with this diameter and length combination to precisely follow the manufacturer's prescribed additional amount of refrigerant per metre of run, on top of the unit's basic charge - failing to correctly calculate this value is among the most common causes of underperformance after installation on a longer run of larger diameter.

Refrigerant flow noise at high flow rates

At high outputs and larger refrigerant flow rates, for which this diameter combination is intended, the noise level of the flow inside the pipe depends not only on the correct diameter but also on the quality of the run's routing - sharp bends, unnecessary narrowings, or loose fixing of the pipe to the building structure can cause audible flow noise or vibrations transmitted into the structure, especially at higher compressor output during peak cooling or heating. A well-routed run with a sufficient number of flexible clips minimises the transmission of vibrations from the pipe into the building's walls or ceiling structures, which is all the more important with this largest diameter and longest run in the range, as it is the section with the highest refrigerant flow rate in the entire system. If you have any doubts about the suitability of this combination for your specific set of units, please contact us - we will be happy to advise you based on the unit models and planned run length - simply provide the exact designation of both the outdoor and indoor units and the approximate distance between them, including any height difference, so that we can recommend a truly suitable and precise combination of pipe diameters and lengths for your specific planned air conditioning installation.