What types of CLV fireplaces can you choose?

An Opsinox CLV fireplace is available in an overpressure version as well as in a underpressure version. We will now discuss the main differences.

A CLV fireplace with negative pressure

In a CLV chimney with negative pressure, there is negative pressure in the collective flue under all circumstances with regard to the air supply duct. This guarantees that flue gases can never flow back unintentionally. In a traditional CLV chimney with underpressure, flue gases are removed by thermal draft. A fan in the central heating appliance transports the flue gases to the CLV system and sucks the combustion air from the CLV system.

A CLV fireplace with overpressure

In a CLV chimney with overpressure, the flue gases are transported through the system by the fan in the boiler with overpressure. To ensure that flue gases do not recirculate, a non-return valve is fitted in the flue gas outlet or the air intake. A CLV chimney with overpressure can save even more space and money as it is possible to work with smaller diameters.

Some central heating boilers are suitable for connection to under pressure systems, others for over pressure systems and still others can be made suitable for both. The Opsinox technical staff will be happy to assist you with professional advice to ensure you make the right choice.