Save up to 1,200 euros per year on gas heating thanks to efficient flue gas dampers

Maisach, 07 October 2022 – With rising gas prices, consumers are looking for ways to reduce heating costs as winter approaches. Flue dampers offer a cost-effective solution. They avoid heat loss and thus reduce the fuel requirement for gas heating systems. At today’s gas prices, savings of up to 1,200 euros per year are possible, depending on the system and size. Thanks to their low purchase price, the flue gas dampers pay for themselves within a short time and reduce the emission values of the heating system. The retrofittable flue gas dampers from Kutzner + Weber, a brand of the Raab Group, have been tried and tested for years.

This autumn and winter season, in addition to the cold, many consumers and businesses are concerned about the high cost of gas and oil. Since many heating systems consume more fuel than necessary due to technically induced heat losses, there is immense savings potential here. With the help of a flue gas damper, cooling losses in the fireplace during standstill and room heat losses can be significantly reduced.

Energy guzzlers Heat losses

Standstill losses or also operational readiness losses occur because the internal structures of the fireplace, such as the combustion chamber, heat exchanger and reheating surfaces, are cooled by the ambient air during breaks in operation of the fireplace. If the fireplace goes back into operation when heat is required, these elements and the interior of the fireplace must be reheated before the heating gases can deliver their heat output to the heat exchangers, for example.

Space heat losses occur in a similar way. The heated room air flows through the fireplace via supply air openings, latent leaks and design-related openings via the flue gas system into the outdoors. If these temperature losses are prevented, i.e. the interior remains hot or warm depending on the downtime, the heating gases could deliver their power to the heat exchangers immediately after start-up.

Flue gas dampers reduce or completely close the clear cross-section of a flue gas system for fireplaces. They are always placed after the flue gas socket of the fireplace, mainly in the connecting pipe between the fireplace and the chimney. When the heating system is in operation, the damper is open and the flue gases can take their predetermined path. When the system is switched off, the damper closes automatically and the warm air from the heating system cannot escape. This means that less fuel is needed and fewer emissions are produced, which improves the overall energy balance. The efficiency of the fireplace is also increased by the use of flue gas dampers.

Save up to 4,000 kW/h per year

Together with the FH Gelsenkirchen, Kutzner + Weber has quantified the effects of heat loss in a study. The study examined atmospheric gas appliances, i.e. floor-standing gas-fired special boilers and gas-fired boiler fireplaces, like those found in thousands of apartment buildings in European cities and in the boiler rooms of single-family homes. It turned out that the average space heating loss of a small atmospheric floor-standing boiler is 4,000 kWh per year. With a gas price of currently at least 30 cents, the resulting costs amount to 1,200 euros a year – and rising. Due to the relatively low purchase costs of Kutzner + Weber flue gas dampers, plus installation costs by a specialist company, the damper pays for itself in the best case after just a few months, depending on consumption and the model required.

Flue dampers are also suitable for multi-storey residential buildings. If, for example, four gas boilers hang on top of each other in a four-storey house, a so-called multiple occupancy, the chimney cross-section is larger than with a single gas boiler. Since the appliances run differently depending on the heat demand in the individual residential units, the chimney is usually warm in the winter months and thus more air flows through the appliances that are not currently being operated. A flue gas damper prevents the warm air from escaping and prevents heat loss in the inactive therms.

There are two types of control for flue gas dampers: motorised or thermal. Flue gas dampers with motorised control for fireplaces with electrically assisted operation, for example draught burners, react synchronously by integration into the control electronics of the fireplace. Flue gas dampers with thermal control are regulated by the flue gas mass flow. They are mostly used with atmospheric gas appliances of type B 11, for example gas boilers and continuous flow heaters. They open very quickly at the start of the boiler run and close shortly after the unit is switched off.

The flue gas dampers from Kutzner + Weber can be retrofitted for all types of heating systems. Also and especially for gas heating systems, which are particularly affected by the current price increases. This provides consumers with an efficient and practical cost brake for their heating costs.