Reznor, PVE, Installation Manual EN 2019-11, D301113 iss D Page 15
Natural ventilation openings to
plant rooms for flued heaters
Where the heater(s) is installed in a plant
room and in flue mode (ie without a positive
connection to atmosphere of combustion
air ductwork) the minimum free area of
ventilation opening needs to be -
• At high level 2 cm
2
for each kW of rated
heat input.
• At low level 4 cm
2
for each kW of rated
heat input.
The high level ventilation opening should be
sited on an external wall and positioned as
high as is practical and always within the top
15% of the wall height.
The low level natural ventilation opening
should be situated on an external wall and
be within 1000 mm of floor level for natural
gas and ideally at floor level for L.P.G gas
installations but in any event no higher than
250 mm.
Model
High cm
2
Low cm
2
30
64
128
50
107
214
72
158
316
95
211
422
120
263
525
145
315
630
Table 10 : Minimum Free Area of Natural
Ventilation Openings for flued heaters.
Natural ventilation openings to
enclosures for room sealed heaters
For enclosure applications the minimum free
area of ventilation opening will also depend
upon whether the heater(s) is installed in
room sealed mode (e.g. with a connection to
atmosphere of both flue and combustion air).
Or with flue only (ie without the connection
to atmosphere of a combustion air duct)
Where the heater(s) is installed in a plant
room The maximum temperature within the
plant room should not exceed 32°C and in
room sealed mode (ie with a connection to
atmosphere of both flue and combustion air)
the minimum free area of ventilation opening
needs to be.
• At high level 5 cm
2
for each kW of rated
heat input
• At low level 5 cm
2
for each kW of rated
heat input.
The high level ventilation opening should be
sited on an external wall and positioned as
high as is practical and always within the top
15% of the wall height.
The low level natural ventilation opening
should be situated on an external wall and
be within 1000 mm of floor level for natural
gas and ideally at floor level for L.P.G gas
installations but in any event no higher than
250 mm.
Model
High cm
2
Low cm
2
30
160
160
50
267
267
72
394
394
95
527
527
120
656
656
145
787
787
Table 11 : Minimum Free Area of Natural
Ventilation Openings to enclosures for room
sealed heaters
Natural ventilation openings to
enclosures for flued heaters
Where the heater(s) is in an enclosure and
in flue only mode (ie without a positive
connection to atmosphere of combustion
air ductwork) the minimum free area of
ventilation opening needs to be:
• At high level 5 cm
2
for each kW of rated
heat input
• At low level 10 cm
2
for each kW of rated
heat input
