If you are looking for a side channel fan - or blower - for an industrial application, you will soon find out that there are several different versions. One of the first choices you have to make is: do you choose a single-stage or a two-stage side channel blower?
This may sound like a small detail, but in practice, this difference matters quite a lot. Not only for the performance of your system, but also for its longevity, energy consumption and reliability.
In this blog, we take you into the world of side channel blowers. We will calmly explain the characteristics of these blowers, what exactly is the difference between single-stage and two-stage side channel blowers, and of course: which one fits your application best?
And to make it a little more concrete? We share two real-life examples - from the logistics and wellness worlds - where choosing the right blower really made the difference.
What exactly is a side channel fan?
Let’s start at the beginning. A side channel blower is a type of blower that moves air or gas through a rotating impeller and side channels. Unlike, say, a centrifugal fan, side channel blowers are primarily about reliability, constant airflow and relatively low maintenance.
They are widely used in a variety of industries, think of:
- Vacuum lifters
- Aeration of water (swimming pools, Jacuzzis)
- Pneumatic conveying
- Air transportation in production processes
- Suction of dust or air in installations
But within the side channel fan range, you again have a choice of single-stage or two-stage versions.
And that’s exactly where the first questions often arise.
The difference between single-stage and two-stage side channel fans
The main difference between single-stage and two-stage blowers is in the way the air is moved and pressurized.
A single-stage blower has - as the name implies - one impeller. The air is passed through the impeller once and then moves to the exhaust.
A two-stage blower has two impellers in a row. This means that the air is sucked in first, compressed a little, and then passes a second impeller once more. This creates a higher pressure, but the air displacement (the flow rate) is somewhat lower.
In brief:
- Single-stage side channel fan → lots of air, low pressure
- Two-stage side channel fan → less air, but much higher pressure
But when do you choose what?
We would like to explain this using two practical examples.
Case study 1: Vacuum charging in logistics
Vacuum lifters are a well-known example of an application where a two-stage side channel fan is indispensable.
For example, we came to a customer in the logistics industry. They were working with vacuum lifters to lift heavy bags. Sounds simple, but those bags had a somewhat rough, porous exterior. As a result, there was always a little bit of leakage at the suction cups.
With a single-stage blower, it failed to generate sufficient vacuum. As soon as a bag moved slightly or skewed, the system lost power too quickly.
The solution? A two-stage side channel blower. This blower could build much higher negative pressure and was powerful enough to lift the bags quickly and safely - even with small leaks in the system.
Important advantages in this situation:
- High vacuum in case of leakage
- Fast vacuum building
- Safe operation
- Reliability in daily use
Case study 2: Aeration of Jacuzzis in a hotel spa
A very different application - but equally important - we find in the wellness sector.
For a hotel with several luxury Jacuzzis, we were asked to supply the blowers for the aeration. This is all about experience: powerful air bubbles in the water, without disturbing noise from the technology in the background.
Because the pipes were short and there was little resistance in the system, we chose a single-stage side channel blower here. Perfectly suited because a single-stage blower moves a lot of air at a low pressure.
The result? Jacuzzis with powerful bubbling action, whisper-quiet blowers and energy-efficient installation.
Important advantages in this situation:
- High air displacement
- Quiet in use
- Low energy consumption
- Perfect for aeration without much resistance
Now when do you choose which blower?
Very simply put:
| Application | Best choice |
| Lots of air, little resistance | Single-stage side channel fan |
| High pressure, vacuum, high resistance | Two-stage side channel fan |
But practice, of course, is always just a little more nuanced. Factors such as pipe length, filters, bends and required capacity all play a role.
Need help? We are happy to think with you.
About DOVAC
DOVAC is a specialist in vacuum technology, blowers and industrial air applications. We supply a wide range of side channel blowers, vacuum pumps and spare parts for various industries.
With personal advice, technical support and a large inventory, we will help you quickly and competently.
Would you like to know more about our products or a customized advice? Please feel free to contact us.
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