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Modernising an apartment building inexpensively

Apartment house modernisation

  • General circumstances

    The building was constructed 20 years ago. The thermal insulation is sufficient. But the owner wants to replace the old oil boiler with a current model.

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  • Challenges

    The owner of the house wants to keep the costs as low as possible and therefore does not want to install completely new regenerative heating technology. He only wants to replace what is necessary.

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New and more environmentally friendly heating system

The apartment block consists of six residential units. The landlord wants to modernise the heating technology as simply as possible. Read on to find out how he approaches the project and which systems he chooses.

Judicious modernisation

The landlord knows that oil heating systems do not have any long-term future. But it is still possible to install modern condensing boilers during renovation projects or in new buildings. Due to his positive experiences with his existing oil heating system, he would prefer to remain with an oil based solution – they have proven their worth to him, and this would be the simplest way to replace the system.

The challenges of the project

In terms of environmental protection, the landlord considers using the roof of the building to install an additional solar heating system. The building already has adequate thermal insulation. This is a good basis for being able to operate the future heating system at low cost. Furthermore, the owner looks at having a ventilation system installed during the modernisation project.

Reasons for choosing the new technology

The old appliance has reached the end of its useful life after almost 20 years and will simply be replaced with the new condensing boiler. The solar thermal technology on the roof supports the heating boiler. This cuts fuel consumption and reduces harmful emissions.

If the output of the solar modules is sufficient, it can cover all DHW heating in the summer. This means that the oil heating boiler could remain switched off during this period. Furthermore, the landlords can apply for subsidies for installing renewable energy technologies.

The products for the project

The owner often heard planners and domestic technology experts mention products made by the company WOLF during discussions. As the products can be perfectly combined and have good reputations, the owner decides to follow these recommendations.

WOLF Oil heating COB-2

COB-2 oil condensing boiler

This appliance represents the latest generation of this tried-and-tested technology. It burns more cleanly and economically than older oil appliances.

A particular advantage: the boiler is especially optimised for use in hybrid systems. The model with 40 kW of output is suitable for the apartment block.

WOLF flat-plate collectors F3-1 and CFK-1

F3-1 flat-plate collector

This collector is very popular for use in solar heating systems thanks to its excellent value for money and robust construction.

WOLF decentralised living space ventilation CWL-D-70

CWL-D-70 ventilation unit

These decentralised appliances are ideal for renovation projects as they can be installed separately in individual rooms.

They use the countercurrent principle to supply fresh air without causing draughts and without losing great amounts of heat. They also counteract mould formation in the interiors.

Sounds complicated? Not for us!

It can be complex and time-consuming to find the right solution for your home. We can help you to understand everything that is really relevant to your project in only a few minutes.

Positive effects even without changing the system

As this example shows, even a modest modernisation project that does not change the entire heating system can have noticeably positive effects. Especially if the developer integrates additional modern and ecological components and creates a hybrid system in this way. This can be best achieved by obtaining all components from a single supplier so that they can be optimally combined with one another.

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Advice: oil heating

Products: Oil hybrid 

Project: Simple replacement of an old heating system