Division 2 From 1 January 2018:

All ventilation units, except dual use units, shall be equipped with a multi-speed drive or a variable speed drive.

All BVUs shall have a HRS.

The HRS shall have a thermal by-pass facility.

The minimum thermal efficiency η_{t_nrvu} of all HRS except run-around HRS in BVUs shall be 73 % and the efficiency bonus E = (η_{t_nrvu} – 0,73) * 3 000 if the thermal efficiency η_{t_nrvu} is at least 73 %, otherwise E = 0.

The minimum thermal efficiency η_{t_nrvu} of run-around HRS in BVUs shall be 68 % and the efficiency bonus E = (η_{t_nrvu} – 0,68) * 3 000 if the thermal efficiency η_{t_nrvu} is at least 68 %, otherwise E = 0.

The minimum fan efficiency for UVUs (ην_u ) is

• 6,2 % * ln(P) + 42,0 % if P ≤ 30 kW and

• 63,1 % if P > 30 kW.

The maximum internal specific fan power of ventilation components (SFP_{int_limit} ) in W/(m³/s) is

• for a BVU with run-around HRS

  • 1 600 + E – 300 * q_nom /2 – F if q_nom < 2 m³/s and

  • 1 300 + E – F if q_nom ≥ 2 m³/s;

• for a BVU with other HRS

  • 1 100 + E – 300 * q_nom /2 – F if q_nom < 2 m³/s and

  • 800 + E – F if q_nom ≥ 2 m³/s;

• 230 for an UVU intended to be used with a filter.

If a filter unit is part of the configuration the product shall be equipped with a visual signalling or an alarm in the control system which shall be activated if the filter pressure drop exceeds the maximum allowable final pressure drop.