The plastic flexible flue system is designed for vertical application and may be dragged a maximum of 45° from vertical. In addition, we recommend that the inside dimension of the shaft should be a maximum of 2x the diameter of the pipe to prevent siphoning. A spacer should also be placed every 2 metres to prevent premature wear due to abrasion. When the outside temperature drops below 5° C, the flexible pipe should be warmed up before installation.

See also the installation film on this website.

More infomation

CoxDENS^® PP Flex is a flexible PolyPropylene flue system developed for use with condensing gas- and oil-fired heating appliances. 
In addition, it is ideally designed for structural shafts with bends and is mainly used for shaft renovations in single-family dwellings.

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CoxDENS is Cox Geelen's range of PP plastic products.

CoxDENS is available in single-wall UV-resistant PP or flame-retardant PP, in flexible PP and in concentric assemblies, where the flue is in PP.

It is suitable for high-efficiency, fan-assisted, gas- or oil-fired heaters with flue gas temperatures below 120°C (T120).

Cox Geelen heeft de ECONEXT^® dakdoorvoer ontwikkeld met een aantal bijzondere eigenschappen. Alle ECONEXT^® dakdoorvoeren zijn leverbaar in de concentrische versies 60/100 en 80/125 mm en parallel in 60/60 en 80/80 mm.

No, it is not permitted to install the CoxDENS^® PP Flex horizontally.

The maximum angle at which the CoxDENS^® PP Flex material may be used is 45°.

The single-walled rigid CoxDENS^® PP and the flexible CoxDENS^® PP Flex are both used on oil and gas-fired fan-assisted condensing high-efficiency heaters with a flue gas temperature < 120° C. 

CoxDENS^® PP is also used in our concentric product range with PP flue pipe and outer pipe in plastic, alu or stainless steel.

Als fabrikant kan Cox Geelen u niet in alle gevallen rechtstreeks leveren.

U kunt ons bereiken via algemeen telefoonnummer 043 40 99 500 afdeling verkoop of sales@coxgeelen.com.

Onze medewerkers zullen u adviseren waar u het beste terecht kunt met uw aanvraag.

The maximum permitted temperature for PP materials is 120° C.

Diameter 60 mm: 12,5 - 25 - 50 - 80 meter
Diameter 80 mm: 12,5 - 25 - 50 - 80 meter
Diameter 110 mm: 15 and 25 meter

The 's' in PPs stands for 'schwerentflammbar', i.e. flame retardant. If the PP is exposed to a source of heat and the heat source is removed, the flame extinguishes within seconds. By adding special additives, we create this flame-retardant property, making the product even safer.

No, as a manufacturer, Cox Geelen cannot deliver directly to you.

For consumer orders, we kindly direct you to a technical wholesaler.

Please check our website to see which points of sale you can contact.

If you need advice, you can reach us at phone number +31 43 40 99 500 or email us at sales@coxgeelen.com.

Please refer to the installation instruction of your heating appliance for this. However, more than 25 m is not allowed.

Both are single-walled systems made of PP.

CoxDENS^® PP is bright white and also UV-resistant. All diameters namely 60, 80, 100, 110, 125, 160 and 200 are in white.

CoxDENS^® PPs is translucent in colour, fire-retardant but not UV-resistant. Diameters 60 and 80 mm are translucent, larger diameters Ø 110, 125, 160, 200 and 250 mm are finished in grey.

Both systems can be used interchangeably.

The minimum processing temperature of PP (Polypropylene) is generally above 5°C. We advise against processing PP below 5°C as the plastic becomes brittle and more susceptible to breakage or damage. This property is inherent to the plastic itself and is not related to its fabrication process.

Yes, you can always make a price inquiry with us.
Subsequently, orders and deliveries will be handled through a technical wholesaler of your choice.

Please check our website to see which points of sale you can contact.