Combined+
What is Combined+?
The Vahterus Combined+ is an advanced evaporator solution where a flooded evaporator is equipped with an integrated droplet separator and superheater. By combining these functions within a single shell, Combined+ delivers a compact solution that simplifies installation, reduces footprint and minimises piping requirements. At the same time, the flooded evaporation principle maintains the high efficiency and performance benefits associated with flooded evaporator systems, helping customers optimise overall system operation without increasing installation complexity.
Where to Use Combined+
The Vahterus Combined+ is ideal for applications requiring both the high efficiency of flooded evaporation and reliable outlet gas superheating. Typical applications include industrial refrigeration and heat pump systems using natural refrigerants such as ammonia (NH₃), carbon dioxide (CO₂) and hydrocarbons.
The integrated superheater helps ensure dry suction gas, supporting safe compressor operation during start-ups, variable load conditions and other situations where condensation may occur in the suction line. By combining flooded evaporation and superheating in a single unit, Combined+ offers a practical solution for improving system reliability while keeping installations compact and straightforward.
Vahterus Combined+, an advanced evaporator solution helping customers optimise overall system operation.
Operating Principle in Heat Pump Applications
The Vahterus Combined+ features two dedicated heat transfer sections within a single unit. The primary heat transfer section vaporises the refrigerant from liquid to gas. To maintain the benefits of flooded evaporation, the liquid level is controlled above the main heat transfer area, ensuring efficient heat transfer and stable operation.
A secondary heat transfer section functions as an integrated superheater, increasing the temperature of the saturated suction gas before it enters the compressor. The superheater can utilise either an external heat source or high-pressure condensate, which is consequently subcooled. When hot condensate is used as the heat source, the result is typically COP-neutral. For maximum operating flexibility, Vahterus recommends incorporating a condensate bypass option.
Vahterus Combined+ Solution
The Combined+ concept is available across a range of Vahterus Combined evaporator models, including:
5/3, 6/4, 7/5, 8/6, 9/7 and 14/9. In selected applications, larger shell sizes can also be utilised to provide increased superheating capacity and support specific system requirements.
The shell pressure and temperature ratings remain in line with standard Vahterus Combined designs. The integrated superheater section is available with design pressures of 16, 25, 40 or 60 barg, with higher ratings available on request. The superheater pressure rating can be selected independently of the shell and plate pack design pressure, providing greater flexibility for system design.
Vahterus Combined+ combines flooded evaporation, droplet separation and superheating within a single shell.
Get in Touch with Our Experts
Whether you're considering the Vahterus Combined+, optimising an existing process or exploring innovative heat transfer solutions, our experts are here to help. Backed by decades of engineering experience and trusted by industry leaders worldwide, we work closely with customers to deliver reliable, efficient and future-ready solutions. Let's discuss your requirements and find the right solution together.