Bs6644 - 70Kw To 1.8Mw - elco THISION L EVO Series System Manual

2.4 BS6644 – 70kW to 1.8MW
Open Flued Type B and Room sealed Type C Appliances Installed within an Enclosure (Natural
ventilation requirements direct to Outside Air.)
Flue type
Open flue Type B
Room sealed Type C
Open Flued Appliances Installed within a Boiler Room (Natural ventilation requirements direct to
Outside Air.)
Open flue Type B
Low Level (Free Area / kW)
High Level (Free Area / kW)
Balanced Flued Appliances Installed within a Boiler Room (Natural ventilation requirements direct to
Outside Air.)
Room sealed Type C
Low Level (Free Area / kW)
High Level (Free Area / kW)
Room sealed appliances with an Maximum Operating Pressure not exceeding 100 mbar in ventilated
occupied spaces with an air change rate exceeding 0.5 air changes per hour do not require additional
ventilation. If the air changes rate is below 0.5 per hour, 2 cm
shall be required.
Open Flued Appliances Installed with a Draught Diverter (Mechanical ventilation flow rate requirements
direct to Outside Air.)
System Type & Operational Time Grille Location
Low Level Inlet (m3/h / kW)
High Level Extract (m3/h / kW)
(Difference Between Inlet and Extract Air)
Open Flued Appliances Installed without a Draught Diverter (With or without stabilizers) (Mechanical
ventilation flow rate requirements direct to Outside Air.)
System Type & Operational Time Grille Location
Low Level Inlet (m3/h / kW)
High Level Extract (m3/h / kW)
(Difference Between Inlet and Extract Air)
Where high level discharge openings are not mechanically assisted, the free area must be calculated as
detailed above. All air inlet and extract fans must be fitted with automatic controls (interlocks) causing
safety shut-down or lockout of the installed gas burning appliances in the event of an inlet or extract air
flow failure.
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Ventilation direct to outside air
5 cm² 10 cm²
5 cm²
Ventilation direct to outside air
4 cm²
2 cm²
Ventilation direct to outside air
2 cm²
2 cm²
Ventilation to an internal space
Not permitted
5 cm² 10 cm²
2 -1
kW ventilation at high and at low level
Ventilation direct to outside air
2.07 +/- 0.18
Ventilation direct to outside air
1.35 +/- 0.18
Not permitted
10 cm²
2.8
2.6