home

CLV-systems
CRO-systems
CRA-systems
Cascade-system
Chimneys
Ventilation-systems
Contact

CRO-systems

With the Collectief Rookgas Optifor (CRO Ð Collective Combustion gases Optifor), Breman IJsselmuiden provides a valuable asset to a market in which a new generation of heating appliances and the recovery of heat energy via the home ventilation system (AGPO and STORK) have already been complementing each other for a considerable time. The CRO system arose from the well-known Collectief Rookgas Afvoerkanaal (CRA Ð Collective Combustion gas Outlet duct). The CRO system is an extended version of the CRA system in which the construction and the diameters of the ducts are matched to the AGFO Optifor appliance in close consultation with AGPO. It is a ventilation product in which the use of modern machines and specialised knowledge are combined effectively.
The proven capabilities of CRO
We can construct the ducts for discharging the combustion products of the combined CRO system in aluminium or stainless steel. The ducts are provided with insulating material with a closed cell structure to prevent condensation on the outside. This construction also makes it possible for condensation that occurs in the exhaust pipe to drain down and be collected. Fresh air can be supplied to the appliance in various ways. The first approach, preferred by appliance manufacturer AGPO, involves placing a collective air intake duct beside the collective exhaust ducts in the service shaft. In this approach, fresh air is drawn in from the roof which allows for no pressure difference between intake and outlet.
The supply ducts are made of concertina tubing, which allows for 6 cm adjustement and are also insulated with a material with a closed cell structure to prevent condensation on the outside of the ducts. We can insulate the ducts in our factory in IJsselmuiden. An alternative approach is where the fresh air for each home is provided by a ventilation duct from the outside wall (constructed with the building or added later).

Summary of the advantages of the CRO system:

  • A gastight system with a limited number of connections per floor, and with built-in drainage.
  • Simple and fast installation.

Consultation with client
The supply and installation of the system is preceded by a comprehensive and thorough consultation with the client in which we can draw upon 20 years of specialist experience. In this discussion, the client, in close consultation with Breman IJsselmuiden, determines the arrangement of the service shaft, the design of the roof plates or chimneys, and their colour. All aspects that affect the other disciplines involved in this work are also taken into account.

Roof fitting for every desired situation
DThe standard roof fitting of the CRO system consists of a cover plate bearing the required pipes. We can extend this construction to a combined roof plate or roof cap. In this extended form, we also incorporate the outlets for ventilation ducts and the sewer vent. It is also possible to provide fittings for a roof ventilator, or transit possibilities for other types of pipes and cables, in the roof caps. The outlets can be supplied in any RAL colour.

Dimensions of the CRO-system

Appliances Diameter of air intake Diameter of outlet for combustion gases
1 150 130
2 200 200
3 250 260
4 300 303
5 355 351
6 400 405
7 450 457
8 500 503
9 500 503
10 560 553
11 630 603
12 630 603
13 710 653
14 710 653
(sizes in mm)

In consultation with the boiler supplier, it may be possible to customize from the quoted sizes. Tables are also available for 20 kW, 25 kW, and 35 kW.


Chimney for sloping roof, 2 x CRO,
and 1 x sewer ventilation