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Collective flues systems for condensing boilers in renovation projects

The development of new condensing boilers, the use of which will soon become widespread, mean that blocks of flats already equipped with individual low-performance gas boilers must be renovated.

Development of condensing gas appliances

Under a general context of a strong rise in the price of energy, strengthening of heat regulations and real consideration for the environment, the choice of heating system during renovation projects is crucial.

The advantages of the condensing boiler are many. By recovering the energy contained in smoke, the condensing boiler enables energy costs to be reduced by 25% to 30%. Condensing boilers guarantee a high level of safety, reliability and comfort and while complying with the new heat regulation requirements:
they can reach an output greater than 108% of the NCV*.

(*Net calorific value)

Renovation of existing flues

In the face of developing those new condensing gas appliances, there is a stock of old dwellings to be renovated. They have flues that cannot be used any more, either because of their diameter, materials or their design, which can prevent the installation of the new generation of boilers.

To secure the highest efficiency of those condensing boilers , it is essential to install adapted and certified flues, of a higher quality and totally tight.

The Poujoulat products provide appropriate responses to the renovation of those blocks of flats, making it possible to install condensing boilers in individual dwellings, in blocks of flats or industrial buildings, whatever the energy used (gas and oil) or power (from 10 kw to 20 MW).

Condensor: lining of an existing traditional brick chimney or building a header and connection for boiler rooms

schema Condensor

Condensor single-wall flue is manufactured from stainless steel and is seam-welded . They are suitable for condensing boilers (gas and oil).

Condensor is the ideal solution for connecting and lining existing flues, in individual dwellings, blocks of flats or in industry. With the creation of a header, several boilers can be connected onto the same chimney.

Condensor is available in a polished stainless steel version and in all RAL colors.

The Therminox double wall insulated chimney is the ideal complement to the Condensor range for outside chimneys.

3 CE P MULTI +: High efficiency collective flue

schema 3  CE P MULTI +

The 3 CE P Multi+ is a collective concentric flue for smoke exhaust and combustion air intake for 2 to 20 individual gas room sealed boilers in a new or existing block of flats.

When renovating, it is the ideal solution in most cases where gas room sealed boilers are difficult to install in a multi-dwelling building block of flats.

The 3 CE P Multi+ combines optimization (smaller space needed for the chimney), efficiency, safety (system securing tightness, fire and condensation resistance), easy installation (press fit connection) and design (stainless-steel or RAL paint color).

Two configurations are possible:

- a stainless steel concentric flue for inside use

- a double-wall insulated flue for outside use

Smoke exhaust for cascade systems

schema Condensor

The Cascade system has been designed for the creation of headers and connection to chimneys with temperatures up to 160°C and running with pressure lower than 200 Pa.

The Cascade system is suitable for smoke exhaust for gas or low-temperature type B22P/B23P boilers installed in line back-to-back.

The diameters available (Ø 150 to Ø 250) have been designed to cover a wide range of boilers’ power, for outside or inside installation.


Find out more about the relevant solutions


Apartment, commercial and industrial buildings

Other websites edited by Poujoulat:

How to install a chimney , a chimney stack ?
How to connect an appliance, and how to line a chimney ?

Cheminées Poujoulat is the specialist in production of metallic chimneys, chimney stacks , accessories for single houses, collective buildings, industrail and offices applications, for new buildings and renovations.
Cheminées Poujoulat offers a wide choice of solutions for flexible and rigid linings, connecting chimneys for all typs of appliances , inserts, wood stove, pellet stove, and boilers. Besides, Poujoulat can offer various solutions to improve the smoke evacuation : smoke extractor fans, warm air distribution, draft regulators, solution for maintening and sweeping the chimneys.

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