Nortek Reznor VRA-4E Series, Installation, Commissioning, Servicing

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1712VRA ‐ 4EGBEN, pag.. 7/25
3.3.2 Combustion air inlet pipe & flue pipe for balanced
flue installation (Type C appliances)
Balanced flue air heaters are designed to be fitted
with a combustion air inlet pipe that obtains outdoor
air and a flue pipe that exhausts flue products to
outdoors. Air heaters if fitted with a power venter
permitting either a vertical or horizontal combustion
air inlet/flue pipe system.
The heaters must be
installed with a concentric vertical or horizontal
flue/combustion air inlet. The heaters are only
approved for use when installed with the
appropriate approved concentric vent terminal.
See table 6. Both the flue and combustion air pipes
must be sealed. Use gasket sealed seamless
aluminium pipe or equivalent. The flue pipe must
include a re-sealable test port to allow good average
sampling of the flue gas mixture for testing, the port
must be at least 450 mm away from the air heater flue
connection socket.
Figure 2b :
Combustion air and flue pipe sockets, Type C
1 Flue products flue outlet socket for flue pipe
2 Combustion air inlet opening
Follow any flue pipe manufacturers’ installation
instructions for making joints, including
connections to the air heater, for passing through
a building element and for support requirements. If
more than one air heater is being installed in the
same place each heater must have a separate flue
system. Where condensation is unavoidable, provision
must be made for the condensation to flow freely
to a point to which it can be released, i.e. a drain
or gully. The condensation drain from the flue must
be constructed from non-corrodible material not
less than 20 mm diameter. Copper or copper
based alloys must not be used for condensation
drains
Table 6 Combustion air inlet & flue pipe requirements
12 20 ‐ 30 35 ‐ 145
mm Flue pipe/Inlet pipe 80 100 130
m
Flue pipe/Inlet pipe 9 9 9
m Flue pipe/Inlet pipe 0,75 0,75 0,75
m Flue pipe/Inlet pipe 1,5 1,5 1,5
m Flue pipe/Inlet pipe 2,5 2,5 nvt Equivalent Length of
90°elbow
VRA ‐ 4E
Heater socket & pipe dia
Max straight length
Equivalent length of 45°
elbow
Equivalent length of 90°
elbow
Concentric vertical vent or wall terminal : Mugro/Burfix dia 130
Concentric horizontal vent or roof terminal : Mugro/Burfix dia 130