PVC Aluminum Duct Hose: Flexible HVAC Combi Duct Guide for Air, Chillers and Blowers

The ECOOSI PVC aluminum duct hose, often called a PVC aluminum combi duct, is a light flexible duct made from PVC foil bonded to aluminum over a spring steel wire helix. It moves air for air conditioning, ventilation, chillers, dehumidifiers and blowers, works from -20 °C to +150 °C, compresses axially at around 1:10, and is supplied in diameters from 51 mm to 406 mm in 10 m lengths.

This guide covers the construction, the sizes and temperature range, the colour options, the applications it suits and the checks that matter at installation.

What Is a PVC Aluminum Duct Hose?

It is a two-material flexible duct. A PVC skin is bonded to a layer of aluminum foil, and a spring steel wire helix is wound into the wall to keep the circular profile. The combination is what makes the duct practical for everyday air work:

PVC outer skin gives an abrasion-resistant, washable surface that handles moisture and general site handling.
Aluminum foil layer gives the wall its shape memory, a smooth bore and a reflective surface, so the duct keeps a clean airflow path when bent.
Spring steel helix holds the round profile under suction and lets the duct compress for transport and storage.

The result is a light duct that stays flexible at low temperature, resists kinking at a small bend radius and can be cut to length on site with a knife.

Construction at a Glance

PVC aluminum foil combi duct in black, white and grey showing the aluminum bore and steel wire helix — PVC aluminum combi duct in black, white and grey, with the aluminum bore and steel helix visible at the ends.

Wall — PVC foil bonded to aluminum foil in a single flexible laminate.
Helix — spring steel wire, spiral wound and bonded into the wall.
Bore — smooth aluminum surface for low friction.
Colours — black, white and grey.
Fire performance — flame and fire retardant build.

Sizes, Temperature and Specifications

Parameter	Value
Material	PVC foil bonded to aluminum, spring steel wire helix
Inner diameter	51 mm to 406 mm
Standard length	10 m per piece
Temperature range	-20 °C to +150 °C
Compression	Axially compressible, about 1:10 extension rate
Bending	Small bending radius, kink resistant
Weight	Light, one person handling for most diameters
Fire performance	Flame and fire retardant
Connection	Push over a spigot or collar, secured with a clamp

Two numbers decide most jobs: the air temperature at the outlet and the diameter the blower or diffuser expects. Stay inside -20 °C to +150 °C, and match the duct bore to the spigot rather than stretching a smaller duct over a larger collar.

Flexibility, Compression and Bend Radius

The duct compresses axially to roughly one tenth of its extended length, which is why it suits service work: a full 10 m run fits in a van or on a shelf, and a length can be pulled out as the route demands. A small bending radius lets it turn out of a ceiling void and into a diffuser without an elbow fitting, and the low-temperature flexibility keeps the wall supple for chiller and cold air supply work rather than stiffening in a cold plant room.

Four-panel view of PVC aluminum duct: aluminum foil wall, reinforced steel skeleton, flame retardant wall and odourless material — Wall build, steel skeleton bending, flame-retardant wall and low-odour material in the combi duct range.

A duct that kinks in a tight bend loses flow exactly where the run needs it most. Keep bends as gentle as the space allows, and where a tight turn cannot be avoided, support the duct on both sides of the bend so the helix does not take the load.

Colour and Light-Blocking Options

The range comes in black, white and grey. The black series is light-blocking and abrasion resistant, which matters where light transmission through the duct wall is unwanted, or where the duct sits in a visible run and should disappear against a dark ceiling. White suits lab and clean-area ceilings, and grey is the neutral choice for plant rooms.

Tri-colour PVC aluminum duct series in grey, white and black with light-blocking abrasion-resistant outer skin — Grey, white and black series: the same aluminum-lined build with different outer skins.

Typical Applications

The duct is used wherever air has to be moved from a unit, a blower or a plenum to a diffuser or a work area:

Air conditioning and ventilation ductwork — flexible branch connections between air handling units, plenums and ceiling diffusers.
Chillers and cold air supply — spot cooling and cold air distribution where the wall has to stay flexible at low temperature.
Dehumidification — connecting dehumidifiers and drying equipment to the space being treated.
Confined space ventilation — portable blower duct for tanks, pits and manholes before entry.
Fans and blowers — utility blowers, axial fans and general air movement equipment.
Wave pool and leisure blowers — high-volume air supply ducting on blower outlets.

PVC aluminum flexible ducts connecting air handling unit plenums to ceiling diffusers in a plant room — Plant room detail: flexible combi ducts link the AHU plenums to ceiling diffusers, held with clamps and cable hangers.

Installation Notes

Cut square and clean. A square cut seats better on the spigot and stops the helix from unravelling.
Use a clamp on every joint. A worm-drive clamp or a quick-release band holds the duct on a spigot far better than friction.
Support long horizontal runs. Hangers every 1.5 m to 2 m stop the duct sagging and keep the helix from carrying the full weight.
Leave a short straight section at the unit outlet. A duct that leaves a fan outlet at an immediate bend loses flow and adds noise.
Keep the wall clear of sharp edges. The PVC skin resists abrasion but will wear through on a cut bracket or a rough thread.
Do not over-compress on installation. Pull the duct out to the length of the run so the helix is relaxed and the bore is round.

Frequently Asked Questions

What is a PVC aluminum duct hose made of?

PVC foil bonded to a layer of aluminum foil, with a spring steel wire helix bonded into the wall. The aluminum gives the bore its smooth surface and shape memory, and the PVC gives the outer skin its abrasion resistance.

What is the temperature range?

-20 °C to +150 °C. The wall stays flexible at the low end, which is why the duct is used for chiller and cold air supply work as well as warm air.

Which diameters and lengths are available?

51 mm to 406 mm inner diameter, supplied in 10 m lengths. Custom lengths and other diameters can be made for project and OEM orders.

How much does it compress?

About 1:10 axially, so a 10 m duct compresses to roughly 1 m. That is what makes it practical to carry and store on service work.

Is it suitable for cold air and chillers?

Yes. The low-temperature flexibility keeps the wall supple in cold plant rooms and on cold air supply runs, without the stiffening that affects some thinner foil ducts.

Can I get a black light-blocking version?

Yes. The range is available in black, white and grey, and the black series is light-blocking and abrasion resistant while keeping the same aluminum-lined construction.

Is it flame retardant?

The duct is built with a flame and fire retardant PVC and aluminum laminate. Check the requirement for the specific installation with your local code before specifying it for a plant room or a public building.

Choosing the Right Duct

For everyday air movement — air conditioning branch runs, chillers, dehumidifiers and blowers — the PVC aluminum combi duct covers 51 mm to 406 mm and -20 °C to +150 °C with about 1:10 compression. The PVC ducting range covers related PVC duties, the aluminum ducting range covers higher pressure and higher temperature foil builds, and the four-layer aluminum foil guide explains when a heavier wall is worth the extra cost. For diameters, samples or OEM packaging, contact the ECOOSI team.