Heat, energy & performance
The baffle filters are where grease first bites and where the easiest energy is lost. Every gram of grease narrowing a baffle raises the pressure drop the fan must overcome, and that pressure feeds straight into energy use. Clean filters are the cheapest, fastest way to keep an extract efficient.
The short answer
The baffle filters are where grease first bites and where the easiest energy is lost. Every gram of grease narrowing a baffle raises the pressure drop the fan must overcome, and that pressure feeds straight into energy use. Clean filters are the cheapest, fastest way to keep an extract efficient.
The detail
Baffle filters are the primary grease filter in a DW/172 system, set at 45 to 60 degrees so grease impinges on the metal and drains while air passes through. They are the first line of grease capture, which means they are also the first component to load up between cleans.
A clean baffle has a known pressure drop. As grease coats it, the gaps narrow and the pressure drop rises - the filter becomes harder to pull air through. That extra pressure is added resistance for the fan, and through the fan laws it translates directly into higher energy use or lost airflow.
Because filters load first and fastest, they are where a small, regular effort pays best. Degreasing or swapping baffles on a sensible schedule keeps the pressure drop low continuously, rather than letting it climb through the whole period between deep cleans and drag energy use up with it.
Filters are only the front of the system, though. Grease that gets past loaded baffles goes on to coat the plenum and duct, so filter care and full system cleaning work together. Clean filters keep the day-to-day resistance down; a full TR19 clean clears what has moved downstream. Left unchecked, that downstream grease is where the larger pressure penalty and the greater fire risk both accumulate, which is why filters alone never tell the whole story.
What it means for you
Filter care is the highest-return maintenance an operator can do. It is quick, it needs no roof access, and it directly holds down the pressure drop that drives fan energy. A kitchen that keeps its baffles clean is keeping its extract near its efficient point almost for free.
But filters cannot be the whole plan. Once grease is past the baffles into the plenum and duct, only a full clean recovers that airflow. The two together - routine filter care plus periodic TR19 cleaning - keep the system efficient across its whole life.
Phoenix Duct Clean handles the full system, and can advise a filter routine that keeps the pressure drop low between visits - so your energy use stays down all year, not just after a deep clean.
The service behind the guide
Sibling guides
Heat, grease and the summer season · Make-up air and airflow balance · Stadium and event kitchen cleaning
Questions
Grease narrows the gaps in a baffle filter, raising its pressure drop. That extra resistance feeds through the fan laws into higher energy use or lost airflow. Clean filters keep the pressure drop low and the fan efficient.
Baffle filters are the primary grease filter in a DW/172 system, angled at 45 to 60 degrees so grease impinges and drains. They capture grease first, which also makes them the first component to load up and restrict airflow.
It depends on cooking volume, but because filters load first and fastest, frequent degreasing or swapping gives the best return. Keeping them clean continuously holds pressure drop and energy use down between deep cleans.
No. Grease that passes loaded baffles coats the plenum and duct, and only a full clean recovers that airflow. Routine filter care plus periodic TR19 cleaning together keep the system efficient across its life.
Yes. As the primary grease filter, clean baffles reduce the grease reaching the duct, which lowers both fire risk and downstream fouling. So filter care supports airflow, energy, fire safety and cleaning intervals at once.
Phoenix Duct Clean · by the numbers
Grease in the baffles costs energy daily. Book a TR19 clean and get a filter routine that holds.