Focus on your product

Individually designed, planned and manufactured – with state-of-the-art technology

HOF systems – state-of-the-art technologies for practical applications

Equipment and systems from HOF are designed and implemented precisely to your individual requirements. We use state-of-the-art technologies in the equipment and systems to achieve excellent results.

HOF systems are often highly innovative and many new developments have been patented. HOF products can be characterized in three words which are important for pharmaceuticals and biotechnology: future-proof, powerful and practical.

HOF is known for innovative products which are developed precisely to the customers’ requirements using the latest technologies and a lot of know-how. As in all our systems, our service also proves that HOF is the specialist for individual solutions. Our systems a glance:

  • Laboratory systems (GLP)
  • Vial production systems (GMP)
  • Bulk production systems (GMP)
  • Loading and unloading systems (GMP)
  • Freezing and thawing equipment (GMP)

HOF freeze drying systems – customised, reliable and easy to operate

HOF freeze drying systems are tailored individually and precisely to the task at hand and to the specific production requirements. For systems which are required for research or for product and process development, we guarantee that the respective process parameters are fully transferable to the production systems. That ensures reliable production!

And: Each system is ideally adapted to the structural environment on site.

Keeping an overview with HOF software

The specially developed software from HOF makes the process control of HOF systems particularly user-friendly. All functions are always visible at a glance and any irregularities are identified immediately.

An optional remote control function provides reliability in production, because the cause is analysed precisely straight away in case of a malfunction.

Our own products also include a visualisation system for creating product-specific temperature profiles, system visualisations and batch-based documentation of processes.

Vial and bulk systems – variety in top quality

Freeze drying systems

HOF is the specialist for individual solutions. That is why freeze drying systems are tailored individually and precisely to the task at hand and to the specific production requirements. And: This allows us to ideally adapt each system to the structural conditions on site. In this area, HOF offers a wider range of freeze drying systems, with regard to system size, model variants and optional equipment. The portfolio ranges from small pilot systems with a footprint from 2.5 m2 to systems with a footprint of 75 m2.

The following equipment variants are available:

  • Vertical design
  • Horizontal design
  • Modular technical units which can be installed according to the building situation
  • Door concepts:
    • single door
    • double doors (facing as a reach-through system)
    • slot door especially for automatic loading and unloading systems
    • slot door integrated into swivel doors
  • The systems can be equipped with different cleaning and sterilizing units for aseptic processing areas and with systems for decontamination of the system periphery.
  • System design for drying products with organic solvents
  • Systems for process monitoring and process analysis
  • Refrigeration systems:
    • two-stage refrigeration sets with synthetic refrigerants
    • cascade refrigeration sets with natural refrigerants
    • LN2 refrigeration via heat exchangers for the installation areas and the ice condenser
    • LN2 refrigeration as direct evaporation for the ice condenser

For the vacuum systems, HOF offers different variants for different requirements:

  • Oil sealed rotary vane pumps with or without Roots-type blower
  • Glandless pumps with Roots-type blower
  • Screw compressor with or with or without Roots-type blower
  • Upstream or downstream exhaust gas filtration

As a specialist for individual solutions, HOF can also supply systems for different requirements in bulk production:

  • Systems with fixed shelves for loading with trays
  • Systems with hydraulically height-adjustable shelves for easer tray handling
  • Systems with tilting shelves for cascade filling, with the shelves designed as product pans The CIP/SIP process can be used here to reload the system with products without opening the chamber door.

Different systems are available for unloading. These are selected according to individual requirements. The same options are available for vial and bulk production systems.

Laboratory systems – optimum system technology, optimum equipment

The customised laboratory systems from HOF with very high quality are used in many renowned companies and scientific facilities for research purposes and for product and process development.

Highly efficient product results

HOF offers the modern systems in compact or split design with a footprint of 0.2 to approx. 2.5 m2. Control, visualisation and technical operation correspond to that of a production system. Transferring the determined process parameters to a production system is made easier and forms the foundation for reliable production. Each HOF laboratory systems consists of a fully functioning basic unit. Individual equipment variants for customised solutions are also available, providing the required flexibility for the task at hand.

Technical data

  • Total footprint: 0,22 m2 to 2,5 m2
  • Number of shelf sets: 3+1 to 7+1
  • Dimensions of shelf sets (mm): 250/300; 420/470; 600/600
  • Hydraulic adjustment of shelves
  • Operating voltage: 400 V/50 Hz
  • Cooling from +20° C to -50° C ≤ 40min
  • Heating from -40° C to +20° C ≤ 60 min
  • Temperature range from -55° C to +80° C (optionally down to -60° C)
  • Evacuation time from 1000 mbar to 0,1 mbar ≤ 20 min
  • End vacuum: 5 µbar
  • Leak rate: < 0,01 mbar*l/s
  • Ice capacity: 4 - 40 kg
  • Temperature minimum condenser: ≤ -70° C (optionally ≤ -75° C)
  • Control: Siemens SPS S7-300
  • User interface: HOF Freeze Viewer Professional

HOF Loading and unloading systems - safe and patented

The safe, optimum and integrated transport of pharmaceutical products and primary packing is the core property of the loading and unloading systems from HOF. The large number of models for loading freeze dryers ranges from models for technical centres to production sizes. And: It allows individual adaptation to any layout. The new design was specifically adapted to customer-specific requirements. High performance and reliability are the crucial factors here. The range covers manual, semi-automatic and fully automatic systems. Special packaging materials such as 2-chamber vials or 2‑chamber syringes can be transported with ease. We hold patents worldwide for these technologies.

Versatile and individual

The loading and unloading systems are installed and tested at our own production facility together with freeze dryers or in front of a suitable dummy frame. The clear advantage is the reduced installation and test period at the customer site. Existing freeze dryers can be retrofitted with the innovative loading and unloading systems from HOF to meet future requirements. Depending on the requirements, loading and unloading systems can be designed for insulator or RABS technology.

Bulk systems


  • Robot with filling lance
  • Robot with suction device
  • Product separator


  • Filling trolley with dosing system
  • Filling trolley without dosing system


  • Lances for filling process
  • Lances to the filling process
  • Product separator

Vial systems


  • Magazine filling
  • Manual transfer trolleys to freeze dryer
  • Semi-automatic loading and unloading
  • Automatic loading and unloading

Frameless row by row

  • Loading and unloading row by row
  • Loading row by row
  • Unloading row by row
  • Unloading multi-segments
  • Batch loading for trolley systems

Frameless by shelf

  • Loading and unloading trolley system
  • Loading trolley system
  • Unloading trolley systems

HOF smartVTS: Vial transfer system

S – safe
M – modular
A – automated
R – reliable
T – time-efficient

The demand for high-quality loading and unloading systems for freeze-drying systems in the pharmaceutical and biotechnological industry is increasing and, with it, the technological requirements. HOF fulfils this need - with the right innovative answers and the expansion of reliable and high-quality production.

Therefore, new developments have been continuously implemented in the field of loading and unloading systems in the past. The new HOF smartVTS meets the highest customer demands and is a good example of HOF’s knowledge, creativity and innovative power.

Reliable, functional and easy cleaning processes

Reliability and fast detection of individual objects all the way to hygienic design are crucial for HOF plant sensor technology. The same with the HOF smartVTS.

The latest sensor technology made of stainless steel with adequate shape requires high functionality and guarantees optimal cleaning and sterilization results.
Production reliability is additionally increased by not having to readjust the positions during possible sensor replacement.

All machine parts in the classified area have been tested with regard to the hygienic design so that the largest possible radii, selection of materials and easy disassembly for the cleaning process have a decisive influence on the results.

Shorter changeover times

Changeover times with varying vial sizes will be significantly reduced in the future with the HOF VTS series through a simplified functional design of the format parts. The same with the new HOF smartVTS.

An exchange of format parts in a cRABS or an insulator is simplified even by glove intervention. Format parts with bottleneck guides are used at certain points to increase production safety.
All format parts are designed to avoid confusion.

Flexible control technology and intuitive user guidance

In the future, control technology of the loading and unloading systems will focus on the new possibilities offered by Siemens as part of the TIA Portal (Totally Integrated Automation Portal).

The user software’s user interface has been oriented towards the future and has been specially designed for application in the clean room. This increases flexibility and guarantees state-of-the-art, needs-based technical solutions.

Intuitive operator guidance via touchscreen, permanently assigned function keys or a combination of both, new control panels used by HOF, now standardized, provide an optimal solution for users. Displays with a wide viewing angle ensure an optimal overview of all plant conditions.

The HOF smartVTS sets new standards for design, technology and functionality


  • Format widths up to 1520mm
  • Fixed side guides on the individual positioning plates, transfer plane and buffer surface
  • All stainless steel components in contact with the packing device are provided with an FDA-compliant coating to minimize friction.
  • HOF VTS can be used both in the RABS and in the isolator
  • Mechanical connection between the individual panels and the transfer level to ensure a clean transition between components
  • Unloading unit inside the freeze dryer (ejection unit’s CIP and SIP, no additional space required in the equipment room behind the freeze dryer)
  • Bellows optionally made of PTFE or stainless steel
  • Format-independent horizontal vial ejection
  • Format-independent horizontal vial recognition
  • Small format parts for easy handling
  • Short changeover times through the use of universal format parts
  • Easy sensor replacement without reorientation
  • All format parts can be mounted or adjusted without tools


  • Row-by-row loading after single-lane feeding of vials by the upstream machines
  • May be discharged as single row or multi-row
  • Vial neck guides at critical points to improve vial stability at high levels of performance
  • Automatically-swiveling hexagonal stopper for transporting vials
  • Correction value entry for hexagonal stoppers for vial tolerances
  • Freely adjustable system output of 20-100%
  • Verification of row length before transferring on the buffer surface


  • Band body as open construction for improved H2O2 decontamination is possible
  • Hygienic design sensors with resistance to H2O2 and all common cleaning agents
  • HOF WIP cleaning system (wash-in-place), for example, toxic applications
  • Material selection is based on common cleaning agents for highest possible resistance


  • All drives are provided as servomotors with integrated absolute encoders
  • Operation of the loading/unloading system and freeze dryer through a control panel
  • Input table for precise positioning and identification of sample vials

Operating modes: Production, Cleaning, Service, Sensor test

PAT technolgy:

  • Automatic exchange of normal plugs against prepared plugs with wireless temperature sensors at a freely selectable position on the positioning plate
  • Automatic removal of vials with wireless temperature sensors before transferring vials to the crimper
  • Detection of prepared vials via camera system
  • Fully automated stopper handling via robot system (clean room-suitable, H2O2-resistant)

Freeze-Thaw Units – precise processes and own software

Adjustable freezing speed and full control over the freezing process are among the top specifications for freezing systems from HOF. The total fill quantity is frozen evenly and independent of the bag size.

Each product bag has the same freezing conditions and, at the end, the same shape. This allows bar codes to be machine-read on the flat surface, for example of a plasma bag. The reliable documentation of temperature and time are a matter of course.

Freezing systems from HOF are energy-saving with indirect refrigeration and use no energy when idle. Large doors ensure fast loading and unloading. The interior of the devices are made of stainless steel and can be cleaned easily.

HOF FTU Plasma: Freeze-Thaw Units for blood transfusion services

Adjustable freezing speed and full control over the freezing process are among the top specifications for freezing systems from HOF.

The total fill quantity is frozen evenly and independent of the bag size.

Each product bag has the same freezing conditions and, at the end, the same shape. This makes it possible for bar codes to be machine-read on the flat surface, for example of a plasma bag. Reliable temperature and time  documentation is a matter of course.

Adjustable freezing with full control and proprietary software

Absolutely reliable freezing and thawing

HOF‘s Freeze-Thaw Units guarantee quality-compliant storage of blood plasma because the product bags are frozen within 45 minutes to at least -30 °C at the bag’s core. At the same time, up to 120 bags with a capacity of 400 ml can be processed. The frozen blood plasma can also be safely thawed again.

Custom requirements – individual plant sizes

Because our customers have different product capacities, there are two model types available: On the one hand, systems for processing up to 60 of the 400 ml bags are manufactured and, on the other hand, systems for up to  120 of these bags.

For individual adaptation Plants are divided into two different types. The compact design accommodates all process-relevant components within the device. On the other hand, there is the possibility of split-construction to lower the sound pressure level directly on the device. Here, the refrigeration components outside the unit are mounted on a separate machine frame.

Advantage: uniform heights of bag systems

The integrated pneumatic adjusting plate system compresses the product bags for the freezing process, so that all processed product bags have the same height after freezing.

The product bags also have flat surfaces on both sides: Barcodes can be machine-read and storage is greatly simplified.

Transparent documentation

The HOF Freeze Viewer Professional software developed by HOF is available for the documentation of processrelevant data. This software, which is configured for blood transfusion services, collects data such as bar codes,  process reports and temperature history and either prints them out in the form of a process report or electronically transfers them to a higher-level system.

More than just hardware and software

The device design for blood transfusion services is based on HOF’s state-of-the-art technology. Apart from production, we also offer, as part of the scope of supply, special packaging, transport and handling support, as well as  annual service and maintenance units.

HOF FTU Pharma: Freeze-Thaw Units for the pharmaceutical industry and biotechnology

Adjustable freezing speed and full control over the freezing process are among the top specifi cations for freezing systems from HOF.

The total fi ll quantity is frozen evenly and independent of the bag size.

Each product bag has the same freezing conditions and, at the end, the same shape. This allows bar codes to be machine-read on the fl at surface, for example of a plasma bag. Reliable temperature and time documentation is  a matter of course.

Adjustable freezing with full control and proprietary software

Safe control of all parameters

Reliable process control is indispensable when freezing and thawing pharmaceutical and biotechnological products. The same applies to the adjustable freezing and thawing speed. Here, with the individual Freeze Thaw Units  (FTUs), HOF meets all the requirements of professional users from the industry. The FTUs are each developed and manufactured according to customer-specifi c requirements. Products that have to be fed into bag systems can  be transported into the plant either manually or by means of a semi-automatic loading aid developed by HOF.

Custom requirements – individual plant sizes

Two types are offered in order to respond fl exibly to on-site installation possibilities. The compact design accommodates all process-relevant and electrotechnical components inside the device.

On the other hand, there is the possibility of split-construction to lower the sound pressure level directly on the device. Here, the refrigeration components outside the unit are mounted on a separate machine frame.

Reliable cooling, reliable heating

Product tempering takes place within the FTU via a plate system. The control panels are designed to freeze the entire load evenly and regardless of bag size.

For temperature control, silicone oil is cooled with a separate cooling system or heated with the built-in electric heater. The integrated refrigeration system’s design is specified according to customer requirements. Optionally, a R452A type hydrofluorocarbon compressor system, a natural refrigerant compressor system (ethane/propene), or a liquid nitrogen system are available.

Included in delivery: „HOF Freeze Viewer Professional“

The FTUs are equipped with a visualization system for process control, the „HOF Freeze Viewer Professional“. This system complies with FDA requirements according to 21 CFR Part 11. With this software, specially developed by HOF, all process-relevant data, such as batch reports and temperature profiles can be printed out in the form of a process report or sent to a superordinate system. Customers can create respective recipes for the individual products individually.

Service is one of them

HOF’s FTUs always comply with state-of-the-art technology and meet high safety standards. Apart from production, HOF stands for comprehensive project support. At the same time, the entire project - from plant planning and production at HOF to commissioning - is entirely managed on-site by a project team. HOF is also available during transport and during introduction of training courses and the annual service and maintenance units.

Pioneering alternatives to conventional compression refrigeration

HOF has a long-standing commitment to the issues of environmental protection, climate protection and greenhouse gases. We consequently offer our plants based on
conventional refrigeration technology as well as a whole range of refrigeration technologies that are based on the use of natural refrigerants. Instead of refrigerants with a high impact on the climate, such as R404A/R507A, these plants use hydrocarbons (ethane/propene), liquid nitrogen or – as in the case of our innovative HOF CryoBlizzard cold air machine – air as a refrigerant.


The new innovative technology: HOF CryoBlizzard central refrigeration

Freeze drying with air as a refrigerant

HOF has developed a new process which uses ambient air as a refrigerant and exceeds the current requirements for freeze drying and blast freezing.

This approach is at the core of the new and innovative HOF CryoBlizzard for refrigeration. This cold air machine allows low temperatures to be generated at a very low operating pressure using the cold air process with heat recovery.

The HOF CryoBlizzard as a closed cold air machine is speed controlled and can therefore be run under partial load very efficiently.

Benefits at a glance:

  • Natural refrigerant (GWP 0)
  • Uses ambient air
  • “Scale up” using central cooling
  • Future-proof and not affected by regulations
  • Low maintenance effort
  • High temperature flexibility
  • Low noise emissions
  • Nearly no requirements for machine room installation (pressure analysis/refrigerant)
  • Very low training required and good safety aspect for employees and site

Freeze drying with compression refrigeration

The objective: combining proven technology and the F-Gas Regulations

The compression refrigeration cycle used to be the most commonly used refrigeration cycle. This refrigeration process is based on boiling and condensing refrigerants.
These will have to be replaced or reduced in the future to meet the targets of the European F-Gas Regulation.

Benefits at a glance:

  • No special requirements for the material
  • Proven, tested and optimised technology since 1988
  • Refrigerant in safety group A1
  • Space requirement

Freeze drying with nitrogen as a refrigerant

A simple process with a natural substance from the atmosphere

The advantages of the HOF freeze drying process with liquid nitrogen as a refrigerant are based on the refrigerant itself: Nitrogen is a naturally occurring component of the atmosphere. Delivered by the nitrogen supplier and stored in outdoor tanks, the refrigeration capacity is available immediately and without restrictions.

Benefits at a glance:

  • Natural refrigerant (GWP 0)
  • Simple process
  • Proven since 1994
  • Future-proof and not affected by regulations
  • Low noise emissions
  • Low maintenance costs

Freeze drying based on hydrocarbons as natural refrigerants

Compression chiller as a cascade

The cascade is another variation of the classic compression refrigeration cycle.

The basic principle links several separate refrigeration systems with different refrigerants. For natural refrigerants, we use a two-stage cascade.

Benefits at a glance:

  • Very low GWP ≤ 6
  • High efficiency
  • Experience since 2007
  • Future-proof and not affected by regulations
  • Modular system
  • Reliability

You can find more detailed information in our brochure:

Innovative refrigeration technologies

Pioneering alternatives to conventional compression refrigeration

> Download PDF

For questions please contact Oliver Fleischer available - Department for Refrigeration Technology Development
and Service Management

Phone + 49 6462 9169-0 - fleischero(at)

Our service for you – as individual as our solutions

Only our own employees work on your system at HOF – even long after it has left our factory. HOF employees transport, install and commission your system and also qualify it. This minimises interfaces and excludes problems, saving time and costs.

24 hours service

You can always reach one of our employees in emergencies at +49 6462 9169-0. 24 hours a day, 365 days a year. Why? Simply because we know that our systems are an important part of the production process and that production reliability has to be ensured. Our emergency team from service and production know the system down to the last detail and can help immediately to keep downtimes as short as possible. The on-site warehouse with over 60,000 items ensures that the essential spare parts for all systems are always available without delay.

You can download our HOF Quick Support here.

Qualification – for your reliable production

We qualify your systems in a GxP-regulated environment. Our own qualification department creates the individual qualification and validation requirements for our systems. This includes:

  • Performance specification
  • Project and quality plan
  • System description
  • Risk analysis for system-specific risk scenarios
  • Hardware design specification
  • Software design specification
  • Traceability matrix
  • Calibration and SAT (site acceptance test)
  • Qualification documentation for IQ and OQ

Extensive measurement equipment

The documents are created and coordinated based on a performance specification. HOF carries out the tests planned in the qualification documents. Extensive measurement equipment is available for calibration and qualification. The following are calibrated:

  • Temperature
  • Relative pressure
  • Absolute pressure
  • Vacuum Pirani and capacitive
  • Conductance
  • Flow rate and others

Among others, Kaye validation systems are used for the qualification in the framework of temperature distribution measurements and sterilisation validation. The validation and qualification systems are subject to continuous testing.

Qualified process development

The services provided by HOF also include qualified process development to offer you added reliability. We use our extensive modern equipment and the available laboratory systems to support you in all matters of process control. This allows us to reduce process times and optimise the quality of the dried product where possible. Equipment for resistance and temperature measurement as well as a cryo-microscope are available for detailed examination of your product.

Design and concept studies – individual and excellent integration

A sound concept is always the basis for the success of your project. As a specialist for individual solutions, we ensure the best possible integration of freeze drying equipment and systems in industry and research. Customised concept studies and plans in 2D and 3D form the basis for our joint work. In addition to the functional aspects, other important parameters are also taken into account:

  • Reliability of the system
  • Easy access for service and maintenance
  • Safety
  • Investment and availability of the systems
  • System capacities

Maintenance – safety through regular checks

Regular maintenance is necessary for perfect functioning of your system. We recommend annual maintenance – necessary due to the service life of seals, for example. It is practical to carry out the annual calibration of the measurement equipment and the sensor system at the same time. After completing the maintenance and calibration work, the systems undergo documented test runs. What is important in this context: The HOF team is also available for freeze dryers from other manufacturers!

Training – successfully transfer of knowledge

For the targeted transfer of knowledge, we always offer training courses which are adapted to your company and your system. HOF training courses are designed to familiarise your employees with your individual system fundamentally and comprehensively, reducing downtimes, enabling fast and independent working and increasing productivity. To increase learning success and knowledge transfer, our employees focus on a personal teaching approach based on practical application.


The stocked HOF systems are a well-established and safe investment, due to their short-term availability and superior quality.

A broad portfolio encompassing anything from lab freeze dryer systems to production plants to freezing- and thawing machines is available in our own store for you to choose from.

Before shipping and hand-off, every system is rigorously tested by HOF. This offers safety and guarantees a long service-life. Specific requirements of your unique application can be implemented in the systems.

Any questions?