Fa. Abel Wellpappe in Form GmbH & Co. KG

Climate-neutral and efficient heating with local heat

There are more sensible measures for active participation in climate protection by reducing CO2 emissions than tacking on high personal commitment to roads or runways. Climate protection is more successfully pursued with positive-active participation, and a large number of companies already began taking measures to reduce their CO2 emissions several years ago.

This also includes the Middle Franconian company Abel Wellpappe in Form, which, founded in 1997, is currently the market leader in Europe when it comes to processing corrugated board with heights between 3.6 and 7.2 mm into corrugated board pads and contour-precise molded parts. Moreover, the end products are single-material packaging made of corrugated board, which – another sustainability plus point – guarantees sort-free recycling. In 2022, the packaging specialist had decided to convert its previously oil-fired hall heating systems to local heating. The local heat is supplied by a cooperative company from the region, which generates it from the combustion of biogas and wood chips. With the conversion of its heat supply, Abel will be able to produce climate-neutral from now on.

Specially designed to supply production and logistics halls

LK Metallwaren GmbH supplied and installed decentralized warm air heaters with oil burners for the production and storage halls at Abel Wellpappe in Form since 2007.

After the company opted for local heating in August 2022, the oil burners in the existing LK warm air generators in Halls 3 to 8 were removed and a PWW register installed in their place.

The distribution of local heat is now handled by the existing LK warm air generators.

LK Warm air heater RBW with condensing technology

LK Warm air heater RBW with condensing technology

In Halls 1 and 2, the aging oil-fired radiant system was dismantled and replaced with a new LK GCS (Green Climate System) warm air heater. The newly installed system has been specially developed by LK Metallwaren for the heating and ventilation of production and logistics halls. With it, the two hall areas can henceforth be heated independently of each other via a two-room control system.

The plant is equipped with a mixed air device, through which the hall is supplied with outside air. The operator can independently determine the proportion of outside and recirculated air to be introduced into the hall on a scale of 0 to 100 percent. During the heating period, for example during break times, intermittent ventilation can be carried out via an interval control system, thus saving considerable costs compared to continuous ventilation.

LK Warm air heater GCS (Green Climate System)

LK Warm air heater GCS (Green Climate System)

However, the LK Warm Air Generator GCS is not only capable of converting cold air into warm air: It also goes the other way. In this way, it ensures a pleasant, precisely controllable hall climate via night cooling even in the warm season. For the summer months, summer/night cooling is stored in the control system. By means of this option, the hall climate can be optimized over the cooler night temperatures. The best possible time for this is usually between 11 pm and 7 am. In order to prevent a possible cooling of the hall, a temperature limit can be specified.

Use with other regenerative heating sources

The LK warm air generator GCS can also be used for other regenerative energy sources. For example, for air heating in the hall can be installed a special heating and cooling coil, which is connected to a cascade of several connected heat pumps.

Heat pumps filled with R32 refrigerant or R290 natural refrigerant are used for this purpose. The integrated filter additionally ensures that the intake air is filtered throughout the entire air exchange and thus cleaned of dirt and dust particles.

Reimbursement of costs by BAFA

And there is another significant plus point: those who opt for the GCS can significantly reduce their acquisition costs. The German Federal Office of Economics and Export Control (BAFA), for example, offers support for new installations in the form of subsidies of up to 40 percent. This is another way to save resources!

For the founder and managing director of Abel Wellpappe in Form Roland Abel, the decision to switch from heating oil to local heating has more than paid off. Because: “We now not only have a climate-neutral heat supply, but have also made ourselves independent of the use of finite resources.”

With the LK warm air generator GCS, 100% of the outside air is used to obtain heat via heat pumps

Optimal climate throughout the year

Resource-saving – cost-saving – climate-friendly: With the LK Warm Air Generator GCS, LK Metallwaren has developed a new generation of hall heaters. It guarantees industrial companies optimal climatic conditions throughout the year and does not require fossil fuels.

The war in Ukraine, which broke out in February 2022, has recently made the one-sided dependence of our energy supply in Germany abundantly clear. This makes it all the more important now to create the conditions for a shift away from fossil fuels toward an increasingly self-sufficient supply of renewable energies.
The heating of large production halls or warehouses is a central and also costly component of this supply. With the LK warm air generator GCS the Schwabach-based plant manufacturer LK Metallwaren now provides industrial companies with a heating system that combines all the requirements of an energy supply via regenerative heat generators with the demands currently placed on a modern, maximally climate-neutral solution.

The LK GCS warm air heater – the GCS stands for “Green Climate System” – was designed to operate completely without fossil fuels for the intended heating of the halls. Heat is recovered via an air-to-air heat pump and thus uses the “most cost-effective” resource of all: the air surrounding us. The user can regulate to the exact percentage point the proportion of outside air or ambient air that the GCS warm air heater draws into the hall. Here, air heating takes place via a heating coil specially adapted for this purpose, which is directly connected to the heat pump outdoor units.

When outside temperatures are cold, a drop in heat pump performance must naturally be taken into account. To cover peak loads, the “Green Climate System” uses an electric reheating coil so that fossil fuels do not have to be used in these cases either. The system behaves in its mode of operation similar to

The main focus of the presentation this time will be the presentation of GCS brand warm air heaters and the proven REKU ventilation systems.

Efficient heating – intelligent ventilation

This year, the Stuttgart LogiMAT will again be held with the participation of the plant manufacturer LK Metallwaren. From April 25-27, 2023, this will bring its visitors up to date on the use of efficient, resource-saving hall heating and ventilation systems.

For the sake of the climate, heating industrial halls in a C02-neutral way and using regenerative resources: This is the motto with which LK Metallwaren would like to address interested trade fair participants at this year’s LogiMAT in Stuttgart, including above all logistics operators.

“While we are one of the leading suppliers of hall heating and ventilation systems we are not part of the core family of the industry. However, with the large number of personal and professional contacts that we have made here as exhibitors since 2005, LogiMAT is now one of the most important events in our annual trade fair calendar,” says Sales Manager Harald Wimmer, summarizing the many positive experiences of the Schwabach-based plant manufacturer during its past participations in the Stuttgart trade fair.

The focus of the presentation this time will be the presentation of
warm air generators of the brand GCS
and the proven
REKU ventilation systems
will be. Wimmer: “In combination with state-of-the-art heat pump technology, hall heating and ventilation systems today no longer require fossil fuels. Accordingly, CO2 emissions can be reduced to zero and, in this way, climate protection targets for the non-residential sector can also be met.”

Green Climate System GCS

By using an air-to-air heat pump, the ambient air can be used as a heat source. This ensures both a particularly energy-efficient and environmentally friendly application. The heaters in the hot air generator are thereby piped to the heat pump and filled with R32 refrigerant for further operation. Advantage of plants made by LK Metallwaren: In all plant combinations with heat pumps, the heating element can be operated for heating (direct condenser) or for cooling (direct evaporator). In this way, plant operators can ensure a stable hall climate throughout the year, significantly improving not only the production environment but also the working conditions for employees. Further advantages: Plant technology that is supplied via heat pumps is subsidized by the
Federal Office of Economics and Export Control
with up to 35 percent of the eligible costs.

As an alternative to heat pump technology, LK systems can also be operated with the use of other non-fossil heat generators such as geothermal, wood chips or pellets. Even retrofits can be realized within a short time with little technical effort.

As in previous trade fair appearances at LogiMAT, LK Metallwaren will once again present itself with extensive consulting expertise and streamlined equipment. For the presentation of
heating system and ventilation systems
two 60-inch screens will provide the necessary visuals on the 20-square-meter corner stand in Hall 5 Stand 5B26. The sales manager of LK Metallwaren Harald Wimmer as well as Henri Dosse (area manager northwest) and Jan Beyer as further sales representatives will be available for best advice to the fair visitors over the entire course of the three fair days.

Hybrid heating

LK "Green-Climate-System (GCS)" Warm Air Heater

The Climate Protection Act has been in force since August 2021.
The German government has tightened climate protection targets and enshrined the goal of greenhouse gas neutrality by 2045. By 2030, emissions are already to be reduced by 65 percent compared with 1990.

Warm air heater RBW
LK Warm air heater RBW

LK Metallwaren offers three innovative solutions for the heating, ventilation and air conditioning of production, logistics and industrial halls. In order to achieve the climate protection targets in non-residential buildings, LK Metall has combined the RBW warm air heater and the REKU ventilation system with heat pump technology , as well as developing the new “Green Climate System”, which heats industrial halls without using gas as a fuel.

LK Warm air heater RBW with condensing boiler and heat pump technology
LK Warm air heater RBW with condensing boiler and heat pump technology

The hybrid heating system with gas and heat pump technology

The very efficient RBW warm air heater with condensing technology is extended with a heat pump package. The combination of gas as a fuel and heat pumps for heat exchange creates the hybrid heating system. Here, the heat pump takes over the heat generation mainly in the transitional period, i.e. in autumn and spring. In winter, on the other hand, the gas heating only switches on when the outside temperatures are too low to heat mainly with the heat pump.

With the air-to-air heat pump, the air is used as a heat source and thus an efficient and environmentally friendly operation is realized. The heaters in the warm air heater are piped to the heat pump and filled with R32 refrigerant. Additional fan units make independent operation of warm air heater and heat pumps possible. The air-to-air heat pumps used with the new R32 refrigerant significantly improve energy efficiency.

Comparison of the greenhouse potential of refrigerants
Graphic - Global Warming Potential (GWP) over 100 years
Graphic – Global Warming Potential (GWP) over 100 years
Source: IPCC Fourth Assessment Report. Global Warming Potential (GWP) over 100 years.

Compared: 2,088 (R410A) vs. 675 (R32). The advantages of hybrid heating are obvious. Hybrid heating reduces CO2 emissions by up to 30%, significantly reducing the need to burn fossil fuels. Another advantage of hybrid heating is the cooling function, which is provided by the heat pumps at all times. Especially in summer, this additionally improves the hall climate for the staff. LK hybrid heating is used in production and logistics halls. In the case of renovation, a gas hybrid heating system is subsidized by BAFA with up to 30 %.

The ventilation system REKU combined with heat pump technology

The LK ventilation systems REKU are often used in aerosol polluted production areas such as machining fabrications, welding shops and areas with high process waste heat. Filtrations up to class F7 ( New: ISO ePM 2.5) can be used in supply and exhaust air. The filter class can be adjusted depending on the application. With the integrated heat recovery system, up to 84% of the thermal energy contained in the exhaust air is transferred to the supply air via a plate heat exchanger using the counterflow principle. The outside air drawn in is thus heated and fed into the hall. With this technology, the supply air and exhaust air flow is separated from each other. Thus, heat from polluted air can also be used.

LK Ventilation system REKU with heat pump package
LK Ventilation system REKU with heat pump package

In summer, the process waste heat is discharged directly to the outside. The heat recovery is bypassed via a bypass to avoid unnecessary heating. A combination of the LK ventilation system REKU and an air-to-air heat pump does not require fossil fuels. As with the other system combinations with heat pumps from LK Metallwaren, the heating element can be operated for heating (direct condenser) or for cooling (direct evaporator). This added value helps to significantly improve the hall climate. Another advantage is that this combination is also subsidized by up to 35%.

The LK Warm Air Generator Green Climate System
The LK Warm Air Generator Green Climate System

The new LK “Green-Climate-System” (GCS) warm air heater

In order to conserve finite resources, the LK design engineers have developed the new CO2-neutral LK “Green-Climate-System (GCS)” Warm Air Heater developed for industrial halls from 4 m hall height. The “Green Climate System” does not use fossil fuels. The LK warm air heater is installed under the hall roof and draws in either hall air or outside air. Ventilation is provided by highly efficient radial impellers with EC motor technology. The passing air is heated via a heating coil connected to the heat pump. An upstream filter cleans the fresh and hall air supply from impurities. In case of very cold outdoor temperatures, it is possible to use an electric reheating coil. This covers peak loads without having to resort to a fossil fuel.

The system behaves similarly to the heating element in the heat pump in the domestic sector. Here, as in the systems already mentioned above, a heat pump with R32 coolant is used. The new system can thus heat and ventilate the hall during the winter months. In summer, ventilation and cooling is possible. With the new LK warm air heater “Green-Climate-System”, LK Metall relies 100% on the medium electricity and thus on regenerative energy sources. This makes the new plant system particularly eligible for subsidies.

Conclusion: LK Metall relies on energy efficiency and resource-saving systems with its entire plant technology in hall heating.


The new office building of mister*lady GmbH in Schwabach (photo source: LK Metall)

Dust-free feel-good climate without drafts on 4,500 sqm

The German fashion retailer mister*lady relies on energy-efficient heating without dust and drafts. LK Metall installed an innovative heating and ventilation system as part of a new construction of a logistics center for the German fashion retailer mister*lady in Schwabach. An investment that has already proven itself in many ways, emphasizes mister*lady managing director, Rudolf Kempter.

Background: mister*lady GmbH moved its headquarters from Nuremberg to Schwabach. In addition to the new central administration with an area of 6,000 m², two logistics halls with an area of 4,500m² each were built. Each hall has 10 gates, a room height of about 7.50 m and a room volume of about 75,000 m³.

In particular, the climate-friendly heating and ventilation of the logistics halls posed a challenge. Managing Director Kempter was faced with a choice. “The architect, general contractor and other consultants recommended different solutions,” he recalls, “so with new construction, it’s important to find out exactly what the requirements are.” Of course, the warehouse activities had to be taken into account: The approximately 22 mister*lady employees moved about 15 million parts in about one million packages per year in single-shift operation. Around 3,600 arrivals and departures took place at the 10 loading stations.

Since the production halls employ the company’s own staff, Kempter is particularly concerned about their well-being: “A modern and energy-efficient solution was important. To achieve a good indoor climate for our people, the temperature distribution must be even and free of dust and drafts. Rudolf Kempter deliberately decided against using gas-fired dark radiators.

Technical structure of the hot air generators
The warm air generators installed under the ceiling draw in waste heat rising from the hall – such as heat generated by lighting or solar radiation – and filter it. In addition, fresh outside air can be drawn in. The air passes a stainless steel combustion chamber to bring it to the desired room temperature. Turbulent flow of the exhaust gases is generated inside the heat exchange tubes arranged on the left and right, thus ensuring optimized heat exchange. Special air outlets and return air ceiling fans distribute the air flow draught-free in the hall. The hot air distribution is controlled automatically by means of PI differential temperature control via measuring sensors in the working area and on the ceiling.

A control system regulates the temperature of the system intelligently and adapted to the wishes of mister*lady: The hall is heated individually as required. The desired room temperature is freely programmable. After an installation period of only one week, mister*lady was able to put the systems into operation.

Costs in view
Looking back, after a first winter heating season, the managing director’s expectations have been met: “The employees are satisfied. The air layering is super, as promised. The air is distributed evenly. There are no cold or warm corners, no trace of drafts.” The energy consumption is also convincing: “On normal working days, we need an average of 320 m³ of gas during the cold season, which corresponds to a cost of about €80,” says Rudolf Kempter.

Especially in the transitional period, the system does not require the burner to be switched on. Then the accumulated heat under the hall roof is already enough. The return air ceiling fans then distribute it evenly back to where it is needed. Great climate should also prevail in the summer at mister*lady. Here, the good hall insulation and the ventilation system play the supporting role. At night, the system draws in the cold outside air and has already ensured pleasantly cool temperatures in the logistics hall by the time the shift begins in the morning. This makes extra air conditioning superfluous.

Advantage: less space required for hall expansion
Another advantage of the plant will only come into play in the future. Rudolf Kempter has further plans for the expansion of the hall. He would like to add a lattice mezzanine at mid-hall height for administration. No problem thanks to the intelligent air distribution of the RBW 125. “With our heating solution, even the employees on the first floor still get warm feet. In addition, there is no need to maintain a minimum distance, as is required for radiant heaters. The space consumption would have been enormous with probably up to 70 radiant heaters needed in the logistics area,” he concludes.


Warm air heater RBW - Gentle temperatures on 7,700 sqm

Three different temperature ranges for sensitive goods

Euphoniums, cajons and agogos – all these wonderful musical instruments can be found in Treppendorf in the Steigerwald in the 7,700 square meter logistics halls of the Thomann music store. In total, there are about 24,000 items here – from guitars and pianos to stringed instruments and various types of percussion instrument.

“We need a special indoor climate for storing musical instruments,” explains Stefan Thomann, co-founder and project manager for logistics at the music retailer. “The items are very sensitive; for example, if the humidity is too low, the tops of guitars can crack. With temperatures, constant air quality is especially crucial.”

Therefore, the company paid special attention to heating and air conditioning technology. Stefan Thomann: “For the pallet warehouse, we only had low temperature requirements because employees are not permanently working here. In the small parts storage area, on the other hand, we were aiming for a temperature of 16 to 17 degrees. But for incoming goods, it had to be a little warmer. The challenge with the technology: despite the three different temperature areas, it is one large, continuous hall.” This three-part temperature concept was realized by LK Metall. Two RBW direct-heated warm air generators with integrated mixed air equipment were used in the pallet and small parts warehouse, which were mounted on the hall ceiling between the two areas. An RBW warm air heater with integrated mixed air unit was also installed in the goods receiving area.

Music store Thomann
Music store Thomann

Evenly from the floor to the roof

The heating system is controlled by a building management system and several thermostats. If the temperature in one of the zones falls below a programmed set point, the respective heating system automatically turns on. Through the surface of the combustion chamber, the heat released by the burner is transferred directly to the passing air. Thus, up to 95 % of the energy used is converted directly into heat. In addition, further heat exchange of the flue gases takes place through the downstream, countercurrent heat exchange tubes, which are washed by the air flow along the entire length of the plant. At the end of the heat exchange pipes, the heated air leaves the plant via mixed air parts. Individually installed return air ceiling fans ensure uniform heat distribution over the entire height of the hall. A differential temperature control system also optimizes and reduces the temperature differences from the roof to the floor in the entire hall area to around 3 to 4 degrees.

A special feature of the system: the warm air generators can be used not only for heating, but also for ventilation. “In the summer months, the temperature in the hall is driven down by a summer night cooling system,” explains Harald Wimmer Sales Manager at LK-Metall. “This allows air temperature, air quality and air distribution to be adjusted as needed.”

Thanks to the finely tuned heating technology between the halls, the sensitive musical instruments will be safely stored in the future with regard to room temperature.

Efficient and climate-friendly! Heating solutions for large production halls

Regulate 32,000 sqm to constant 18 °C hall temperature

The RBW decentralized warm air generators from LK Metall are an efficient and climate-friendly heating solution for large production halls.

In order to heat the new light-flooded production hall with a total area of around 32,000 m2 evenly and effectively during the annual heating period and to achieve a pleasant hall climate in summer, the axle manufacturer commissioned Kessler+Co. GmbH & Co KG from Abtsgmünd, Germany, provided the LK Metall company with a climate-friendly heating system using effective condensing boiler technology.

A total of 12 decentralized warm air generators of the RBW type were installed over a wide area under the hall ceiling. In order to achieve a uniform temperature of around 18 °C during the heating period, rising hall air is extracted, filtered and heated via the combustion chamber and the designed heat exchangers and fed back into the hall without drafts. The decentralized warm air generators are each heated with a natural gas-fired gas blower burner.

Warm air heater RBW for Kessler+Co
Warm air heater RBW for Kessler+Co

Additional use of waste heat

The rising warm hall air from process heat and the solar radiation via the skylights are an additional usable heat source for the warm air generator. The hall air extracted and filtered under the hall ceiling mixes with supplied fresh air. Due to the additional use of waste heat in combination with the modulating burner operation of the units, the RBW warm air generators consume significantly less energy.

“The use of the decentralized warm air generators type RBW for heating production halls is a convincing contribution to climate protection,” says Harald Wimmer Sales and Marketing Manager for hall heaters at LK Metall, “Because the additional use of waste heat means that less fossil fuel is consumed. This significantly reduces CO2 emissions.” The heat output range of RBW warm air heaters is from 40 kW to 160 kW. Special knitted metal filters made of stainless steel clean the hall air from dust particles and aerosols from production. Around 90 installed return air ceiling fans reduce the temperature stratification over the entire hall height to 0.3 °C to 0.5 °C per rising meter. These are regulated by sensors in the ceiling and floor areas.

Cooled hall air in summer

In the summer months, the RBW warm air generators improve the hall climate through the mixed air device. An automatic night-summer ventilation control system uses the cool outside air at night to cool the hall air, reducing accumulated heat from the day back to a comfortable temperature. “Thus, the RBW warm air heaters are also used in summer to maintain a pleasant daytime temperature,” said Harald Wimmer after commissioning the heating systems at Kessler+Co.

Central control from PC

A modern PLC flexibly controls the warm air generators. All settings are made via the respective touch displays on a total of four control cabinets. In order to be able to operate the twelve warm air generators centrally via a PC, the systems were integrated into the company’s network. Regardless of the size of the production and manufacturing halls, the RBW warm air heaters from LK Metall are a flexible, efficient and infinitely scalable heating solution with an extremely high efficiency of up to 99% based on the calorific value, thanks to the decentralized installation under the hall roof.