The requirements on a ventilation system are not always the same. In many applications, all that is required is a straightforward exchange of air, whereas in other applications the requirements can be very exacting with regard to temperature, humidity and purity of the air. Rosenberg air handling units in the Airbox series have a modular design and  can be individually configured. In this way, the appropriate solution can be assembled using a kind of modular principle for each application in a quick and straightforward procedure. Both, in the high-tech area and for classic building technology, air handling units from Rosenberg deliver clean air at the right tempered room climate. Weather-proof and explosion-proof designs are possible, as well as TÜV certified hygiene variants. The units consist of a framework structure with double-skinned panels that have acoustic and thermal insulating properties. The individual modules for the filter, fan, heater, cooler, heat recovery, acoustic insulation as well as the frame materials, are assembled flexibly according to the customers‘ requirements.

The F40 series is produced in a frameless design. The panels are screwed together from the outside so that the devices are smooth internal surfaces and are hence hygienically safe. The air handling units Airbox A20, S40, S60, T60 are equipped with a framework construction made from aluminium or galvanised, rolled steel profiles and aluminium cast corner connectors or plastic corner connectors. ac unit spare partsIn the case of the Airbox A20, the double-skinned panels are insulated with non-combustible, sound and thermal insulating mineral wool. vibration from ac unitThe Airbox S40, S60 and T60 air handling units are also filled with non-combustible, sound and heat insulating rock wool insulation. through wall air conditioner heater unit

In addition to galvanised steel panels and the framework construction, it is also possible to select coated steel, aluminium and stainless steel versions in our range. For modules with smaller dimensions, the base frame is manufactured in various heights (100, 300, 500 mm) using galvanised, folded steel sheet. Larger modules have a welded base frame (primed or galvanised). 3 mm aluminium profile 1,5 mm galvanised steelor stainless steel 1,5 mm galvanised steel 1,5 mm aluminiumand thermally decoupled The main factors which are important for the energy efficiency of an air handling unit are the air velocity in the profile unit face as well as the electric power consumption of the fan which is dependent on the air volume and pressure increase. In a combined air handling unit with heat recovery (HRU), the efficiency and pressure loss of the heat recovery must also be taken into account. We work in accordance with the statutory requirements of the German Energy Saving Ordnance (EnEV), as well as the requirements of the German AHU Manufactures Association (RLT) when selecting the parameters for air velocity, the electrical power consumption of the fans and the efficiency of heat recovery.

The criteria of the RLT energy efficiency label correspond to the standard DIN EN 13053 A1 (2011). This standard defines nine air velocity classes from V1 to V9, six heat recovery classes from H1 to H6 as well as six classes for the power consumption of fans from P1 to P6. The specific power consumption of a fan (SFP), installed in the air handling unit, is calculated as defined by the current DIN EN 13779. Air velocity class without thermal air treatment Air velocity class with air heating and / or heat recovery Air velocity class with additional functions Electric power consumption class Heat recovery classes (4,000 - 6,000 hours per year) > 1,6 to 1,8 > 1,8 to 2,0 > 2,0 to 2,2 > 2,2 to 2,5 > 2,5 to 2,8 > 2,8 to 3,2 > 3,2 to 3,6 The accuracy of the data output by our AHU selection software is regularly checked and certified by TÜV Süd, on behalf of the RLT association. For more information about the RLT energy efficiency label, refer to the AHU guideline 01 from the German AHU Manufactures Association (RLT).

Test certificate of energy efficiency labelFile format: .pdfFilesize: 632.69 kB Performance experiment of all fresh air-handling unit with high sub-cooling degree and year-round exergy analysis Zhongbin Zhang, Yamei Pan, Hu Huang & Qing Jiang In this article, an all fresh air-handling unit with high sub-cooling degree is presented. In this unit, refrigerant flows through the high-pressure liquid receiver before it goes through the sub-cooler so as to ensure sufficient sub-cooling degree. Based on the experimental comparison between this unit and conventional unit, coupling relationships between condensing temperatures and sub-cooling degrees of these two units are worked out and analyzed. Experimental results and exergy analysis show that, sub-cooling degree drops with the decrease of condensing temperature, and sub-cooling degree of the designed unit is kept over 7°C when the sub-cooling degree of the conventional unit is only close to 0°C. Furthermore, a method of year-round exergy calculation is presented and applied in calculating and analyzing the year-round exergy of the all fresh air-handling unit.

Calculation and analysis show that the all fresh air-handling unit designed and investigated in this article has a year-round exergy efficiency of 28.38%, which is 3.17% higher than that of the conventional unit without high sub-cooling degree.Engineering room airflow may present a real challenge when balancing an HVAC system. Most calculations only use the heat loss or gain of a room to decide on required airflow and often don’t take into consideration required room ventilation needs. Let’s take a look at how an air change calculation may simplify this step in your air balancing. What is an Air Change? An air change is how many times the air enters and exits a room from the HVAC system in one hour. Or, how many times a room would fill up with the air from the supply registers in sixty minutes.   You can then compare the number of room air changes to the Required Air Changes Table below. If it’s in the range, you can proceed to design or balance the airflow and have an additional assurance that you’re doing the right thing.

If it’s way out of range, you’d better take another look. To calculate room air changes, measure the supply airflow into a room, multiply the CFM times 60 minutes per hour. Then divide by the volume of the room in cubic feet: In plain English, we’re changing CFM into Cubic Feet per Hour (CFH). Then we calculate the volume of the room by multiplying the room height times the width times the length. Then we simply divide the CFH by the volume of the room. Here’s an example of how a full formula works: Now, compare 7.5 air changes per hour to the required air changes for that type of room on the Air Changes per Hour Table below. If it’s a lunch or break room that requires 7-8 air changes per hour, you’re right on target. If it’s a bar that needs 15-20 air changes per hour, it’s time to reconsider. Let’s look at this engineering formula differently. For example, what if the airflow is unknown and you need to calculate the required CFM for a room? Here is a four-step process on how to calculate the room CFM: Step One – Use the above Air Changes per Hour Table to identify the required air changes needed for the use of the room.

Let’s say it’s a conference room requiring 10 air changes per hour. Step Two - Calculate the volume of the room (L’xW’xH’). Step Three - Multiply the volume of the room by the required room air changes. Step Four Divide the answer by 60 minutes per Hour to find the required room CFM: Here’s an example of how to work the formula: When designing or balancing a system requiring additional airflow for ventilation purposes, remember this room will normally demand constant fan operation when occupied. This may present a problem for other rooms on the same zone, so take that into consideration. Many of these rooms may require a significant amount of outdoor air. The BTU content of this air has to be included in the heat gain or heat loss of the building when determining the size of the heating and cooling equipment. Practice these calculations several times in the shop or office. Then do the calculations in the field several times over the next week to check airflow in rooms with uncommon ventilation requirements.