In many sectors, such as the food industry, energy industry, logistics, mechanical engineering or building services engineering, cooling is always system-relevant and critical for the quality of processes and thus the final products. The reliability of the heat exchangers in terms of fail-safety, hygiene and energy efficiency is the focus here. With the range of different applications, heat exchangers are exposed to a variety of demanding environmental conditions that can affect their lifetime.
If your heat exchanger is defective, regardless of the brand, Roller, as a manufacturer of high-quality heat exchangers, will be happy to assist you with consultancy and rebuilding. It is important to us to analyse the cause of the defect and to provide you with a more resistant replica with a long service life.
This page gives you an insight into the performance of the 1:1 replica of your high-quality heat exchanger.
Corrosion in food display counters
In food retailing, the requirements for air coolers are as various as the range of food on offer. In food display counters in particular, a wide variety of factors such as amines, salts and organic acids (e.g. acetic acid) have an effect on the heat exchanger due to the often open meat and sausage products, salads, marinades and other dishes. Humidity, cleaning agents and mechanical influences do the rest. The use of suitable material combinations, coupled with proven corrosion protection coatings, reliably withstands corrosive attacks.
Verdigris on copper pipes
Salts, vinegar, smoke or even cleaning agents have a damaging effect on the air coolers in cold rooms. Here it is important to know the effect of these influences on corrosion. Copper, oxygen and acetic acid react to form copper acetate and water. This is easily recognisable by the green colouring. Compared to patina, verdigris occurs locally and is associated with an increase in volume. Moreover, verdigris is toxic! This necessarily leads to leaks and can cause problems with the food safety authorities.
Use of incorrect materials
External influencing factors are also responsible for the performance of heat exchangers outside of food refrigeration. Based on the chemical fundamentals, the assessment of the exchange effect of individual substances is of high importance. This heat exchanger made entirely of aluminium was not suitable for use in a potash and salt mine. In this case, the solution was a replica made entirely of copper.
Pollutant gases from sewage pipe
Improper installations also affect the lifetime of heat exchangers. This very localised corrosion attack stems from a missing siphon in the condensate drain pipe below the air cooler. The aggressive pollutant gases from the waste water line attacked the aluminium fins here and led to the collapse.
- Corrosion in food display counters
- Verdigris on copper pipes
- Use of incorrect materials
- Pollutant gases from sewage pipe
For the sake of the environment
- Extending the service life of your entire plant
- Ensure future-proof operation of the plant
- Ensure energy efficiency requirements
- Increase reliability
- Prevent leakage due to corrosion
- Savings through adaptation to changed plant parameters
- Contribution to climate protection through energy-efficient operation
- Short delivery time, for minimum restriction of operating procedures
- Large selection of standardised heat exchangers for common cooling cabinets
- Manufacturer-independent reproduction also in batch size 1
- Identical dimensions eliminate the need for conversion work on the tubing
- Competent consultancy in the event of changes to system parameters (refrigerant, refrigerated goods,...)
- On-site measurement on request
- Advice on ideal corrosion protection
- Wide range of corrosion protection options
- Various fin materials
- Tinned tube over the entire length for increased reliability against corrosion
Highest material quality
- Use of high-quality copper tubing primarily from German manufacturers
- Heat exchanger coil for an operating pressure of 16 bar / 80 bar with high-pressure refrigerants (CO2/ R744)
- Core tubes in copper CuDHP with thick walls
- Possible fin spacings: 2.0 / 2.5 / 3 / 4 / 4.5 / 6 / 7 / 8 / 10 / 12 mm (others on request)
- Core tube with smooth or grooved inner surfaces
Quality and pressure checks
- Production in accordance with the Pressure Equipment Directive 2014/68/EU
- Pressure checks on units with water/brine: 18 bar overpressure
- Pressure checks on units with coolant: 27.5 bar overpressure
- Pressure checks on units with high-pressure refrigerants: < 27.5 – 115 bar overpressure
- All units are subject to an exacting outgoing quality check
- Special checks when flammable coolants are used
- Use of the highest quality materials from primarily German brand manufacturers
- Robust products with maximum energy efficiency and durability
- Fast processing times for shortest delivery times
- Quality manufacturer with unusual flexibility
- Reliable spare parts supply at short notice
- 75 years of strong relationships with our customers
Wide range of applications, e.g. in meat and sausage cabinets with fan-guided air circulation or free cooling
Used e.g. in catering refrigeration units and cabinets in various design variants with refrigerant, water or brine
Various designs to be used in a wide range of cooling and air conditioning scenarios with almost all refrigerants
Highly efficient, interconnected supply and exhaust air heat exchangers for efficiencies of up to 80% with very low air-side pressure losses - TÜV type-tested
are designed so that the circuits are arranged in intermeshing or parallel form in a heat exchanger coil. They are very popular where space is limited or as a redundancy solution
These fins can be used in the long term with slightly aggressive ambient air
Offers excellent protection against aggressive atmospheres with uniform coating of the entire block ( fin, tubes and end plates)
Here, a vinyl-based epoxy coating against slightly aggressive substances and the hydrophilic fin for protection in humid atmospheres are available.
According to specification
The unit has already been built by Roller and you have the order number or a serial number. If not, we will define the new heat exchanger based on the requirements of your application.
According to sample
Is it a third-party brand or a Roller order number is no longer available? You are welcome to provide us with your custom sample.
Please feel free to provide us with old technical drawings. If there are no longer any available, please use the measurement guide to specify the reconstruction. Please also enclose photos of the old unit.
Replica - LE - V-shape Re-cooler
Our customer of this heat exchanger needed a short-term replacement of his V-shaped recooler. In his system, this sprayed recooler, consisting of two registers arranged in mirror image, had become leaky due to corrosion and was to be replaced exactly as it had been. Thus, a replica with hydraulic branching/distribution of the media flow and hydrophilic coated fins, which allows the water of the wetted heat exchanger to flow off more easily, was created in the closest possible match to the sample supplied.
The original sample provided to us is available to us as a technical specification in terms of dimensions, pipe geometry, etc. and is usually returned to the customer with the replica unit as proof in a sturdy wooden box. Often there are still various add-on parts on the samples, which may be reused on site.
|Address||Germany / Ingelheim on the Rhine|
|Product||LE - Special design|
Replica - LE/LK - Air handling unit
Cut or in one piece? The task was quite clear: in the several-year old air-handling unit, the original heat exchangers were leaking due to corrosion and had to be replaced. However, the corridor next to the ventilation system is so narrow that a 1:1 replacement is impossible. So, what to do? The old heat exchangers can only be sawn up and taken out piece by piece. The solution for the new heat exchangers is to insert exact-fit heat exchanger modules that are piped in the AHU and hydraulically connected.
|Product||LE / LK|
Replica - LE / LK - Food process cooling
For a chocolate producer from Rhineland-Palatinate, an existing heat exchanger for a cooling tunnel was rebuilt 1:1 and replaced. The required cooling capacity of 77kW with limited space conditions of 1.7 sqm inflow area led to this cubic direct evaporator with 20 (!!!) pipe rows in depth. With a 50x50 aligned pipe system, the pressure loss is kept as low as possible with a volume flow of 13,000m²/h.
Fail-safety is ensured by the split in two interlocked R407C refrigeration circuits, which operate redundantly to each other.
|Application||Food process cooling|
|Address||Germany / Rhineland-Palatinate|
|Product||LE / LK|
Replica - LE / LK - Solvent resistant
The heat exchanger provided to us as a sample for reproduction was used to condensate solvents contained in the air flow. However, the material used did not withstand the aggressive solvents. The Roller rebuild of the evaporator coil was remedied by a version made entirely of copper (corrosion protection variant E), in conjunction with a solder with a very high silver content.
|Product||LE / LK|