Reznor, Photon, Installation Manual, EN 2021-04, D301310 Iss 0 Page No 15 of 52
I
When these units are installed
in Type B applications, air for
combustion is taken from the
space in which it is installed. Do
not restrict the combustion air
intake.
Ensure that an adequate clean
air supply for combustion and
ventilation is provided within the
building in accordance with the
relevant rules and regulations in
force.
Figure 2 Approved appliances Type B
Roof B23 / B53
Wall B23 / B53
1. Combustion air inlet
collar with grille
2. Flue pipe outlet collar
3. Gas connection
1
2
3
Figure 3 Connections on rear of unit
Type C appliances
Unit heaters used in a balanced flue
application are designed to be fitted with a
combustion air inlet duct that obtains outdoor
air and a flue pipe that exhausts flue products
to outdoors.
Single wall seamless aluminium or stainless
steel flue pipes are required. All joints must be
sealed to prevent the products of combustion
from leaking into the building. If the flue
passes through a combustible element of the
building it must be enclosed by a sleeve of
non-combustible material and separated from
the sleeve by a minimum of 25 mm air break.
The temperature of any combustible material
near to the flue must not exceed 65°C when
the heater is in operation. The flue must be
at least 150 mm away from any combustible
material.
Single wall flue pipe exposed to cold air or run
through unheated areas should be insulated.
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.
Vertical flue runs greater than 3m long will
require a condensate drain fitting between the
flue outlet of the heater and the vertical flue
pipe. Alternatively, insulated flue pipe should
be considered.
Horizontal flue runs should be installed with
a slight gradient of approximately 5° towards
the terminal. Due consideration should be
given to the possibility of condensation from
the flue freezing on any footpaths that pass
below the terminal.
