The importance of a clean ventilation system

A clean ventilation system ensures low power consumption, high productivity, and animal welfare

Tommy H. Krogh, Poultry Specialist, SKOV A/S

The housing climate is a critical factor for animal welfare and productivity!

It places high demands on the ventilation system to ensure the correct temperature, air quality, and air humidity, regardless of building, production, and climate conditions.

Why is a clean ventilation system important?

When SKOV dimensions a ventilation system, great importance is attached to ensuring that the animals have the right climate – also during periods when the system runs at maximum capacity.

At the same time, we are very conscious of not delivering a ventilation system that is "oversized," which will make the investment bigger than necessary.

Therefore, the ventilation system must work as dimensioned, especially during the hot (and humid) periods and when the stocking density is high.

In this connection, the farmer must maintain and clean the ventilation system.

A poorly maintained and cleaned ventilation system will give rise to greater power consumption and, at worst, will not ensure good productivity and animal welfare.

Based on many years of experience and tests, we have collected some examples of where we most often see problems occurring and what the consequences for the performance of the ventilation system typically are.

Dirte light trap

What are the consequences of a lack of maintenance and cleaning?

In most of our systems – LPV, Tunnel, and Combi-Tunnel – the capacity and functionality of the air outlet are the substantive factor for the system's performance. The aerodynamic chimneys and wall fans are designed for maximum air output at low energy consumption.

At the same time, chimneys and wall fans must handle the housing air with all the impurities it contains, which is why we often see problems here.

Our experience shows that:

  • A dirty chimney with a fan can lose 12-15% performance.
  • 230V fans contain capacitors, a wearing part that continually loses functionality and must be replaced. The fan may lose 10-50% of its output depending on how worn the capacitor is.
  • Chimneys or wall fans equipped with light traps naturally have a higher pressure loss, which we allow for in our dimensioning. An unclean light trap constitutes an additional pressure loss, quickly reaching 20-40% of the capacity. (Light traps are typically used in breeder and layer productions).
  • If the shutter cannot open completely due to dirt, it may reduce the outlet output by 10-20%.
  • In wall fans, where the fan blade is belt-driven, it will eventually become loose and worn. A more than 10% performance loss is likely if the belt is not replaced or tightened.

Particular focus on older ventilation systems

SKOV ventilation systems work for many years, and we have systems that have been running for more than 30 years. It is imperative to focus on the performance of these old ventilation systems.

They are dimensioned for the genetic potential of the animals at the time the livestock house was built. Fortunately, the potential of the animals has changed positively over the last many years, where the animals have generally become bigger or are performing at an increasingly higher level.

Likewise, the climate in many areas has become more extreme, with higher temperatures and more significant fluctuations.

It means that our dimensioning of older ventilation systems is based on a different reality and that today we would probably have dimensioned an equivalent ventilation system with higher performance.

If the lack of cleaning results in a further capacity reduction of the ventilation system, it can have consequences for power consumption, productivity, and animal welfare!

Our recommendations

In general, SKOV recommends the following:

  • Check if the system is correctly dimensioned in relation to the current production together with your ventilation supplier. It is crucial for older ventilation systems.
  • If the ventilation system is under-dimensioned, devise a reconditioning plan with your supplier. Establishing a high-pressure cooling system that can provide a temperature reduction of 5-7 degrees (depending on the air humidity level) can be a sensible addition to an undersized system.
  • Get a service engineer from your ventilation supplier to review the installation at least once a year before the summer, as this is when the ventilation system must perform at maximum.
  • Develop good routines for cleaning the system and especially the air outlets.