Table of Contents
- Total pressure is the full energy of the moving air; static pressure is the usable pushing force after velocity energy is set aside. Fans are classed by the static pressure they can develop against a system - and the recovery core is one of the biggest resistances in that system.
- The pressure drop across a recovery core (driven by face velocity) must be overcome by the supply and exhaust fans. A higher-effectiveness, smaller core raises pressure drop and pushes the fan into a higher static-pressure class - more motor power and more noise. Selection balances recovery gain against fan penalty.
- EC (electronically commutated) fans hold efficiency at part load, so a recovery system with variable flow keeps its fan energy low even when the core drop is significant. In a retrofit or AHU upgrade, pairing recovery with EC fans captures both the heat saving and the fan saving.
- Is static pressure the same as pressure drop? The core pressure drop is the static pressure the fan must supply across that component; total system loss is the sum of all components. Does a bigger core avoid the fan penalty? Yes, at the cost of size and material; the optimum is found by lifecycle cost, not by minimising either alone. Need help specifying the right air-to-air heat recovery for your project? Contact the QIYU engineering team - WhatsApp +86 157 5335 5505, or email kuns913@gmail.com. Frequently Asked Questions What is fan static pressure class? It groups fans by the static pressure they can deliver, such as low, medium or high pressure, which must match the duct and exchanger pressure drop. Why must the fan match the recovery core? Undersized static pressure starves airflow and cuts effectiveness; oversized wastes fan power, so the fan curve must clear the core's operating pressure drop at design flow.
Total pressure is the full energy of the moving air; static pressure is the usable pushing force after velocity energy is set aside. Fans are classed by the static pressure they can develop against a system - and the recovery core is one of the biggest resistances in that system.
The pressure drop across a recovery core (driven by face velocity) must be overcome by the supply and exhaust fans. A higher-effectiveness, smaller core raises pressure drop and pushes the fan into a higher static-pressure class - more motor power and more noise. Selection balances recovery gain against fan penalty.
EC (electronically commutated) fans hold efficiency at part load, so a recovery system with variable flow keeps its fan energy low even when the core drop is significant. In a retrofit or AHU upgrade, pairing recovery with EC fans captures both the heat saving and the fan saving.
Is static pressure the same as pressure drop? The core pressure drop is the static pressure the fan must supply across that component; total system loss is the sum of all components.
Does a bigger core avoid the fan penalty? Yes, at the cost of size and material; the optimum is found by lifecycle cost, not by minimising either alone.
Need help specifying the right air-to-air heat recovery for your project? Contact the QIYU engineering team - WhatsApp +86 157 5335 5505, or email kuns913@gmail.com.
Frequently Asked Questions
What is fan static pressure class?
It groups fans by the static pressure they can deliver, such as low, medium or high pressure, which must match the duct and exchanger pressure drop.
Why must the fan match the recovery core?
Undersized static pressure starves airflow and cuts effectiveness; oversized wastes fan power, so the fan curve must clear the core's operating pressure drop at design flow.