1307SDH_RDH--EN,
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Figure 6b : Type B appliances – Combustion air and
flue pipe sockets
6.3 Type C appliances
Balanced flue air heaters 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 flue seamless aluminium or stainless steel
pipes are required. All joints must be sealed to prevent
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.
For testing, the flue pipe should include a sealable test
port. The port must be at least 450 mm away from the air
heater flue connection socket.
Follow the flue pipe manufacturers installation
instructions for making joints, including connections to
the air heater, for passing through a building element
and for support requirements.
Type C2 appliances must not be applied !
Figure 7 : Type C appliances - Combustion air and
flue pipe sockets
1
2
Figure 8 : Approved appliances type C
C12
C12b/C62
C32/C62
C52
1 Combustion air
inlet opening
2 Flue pipe outlet
collar
1 Combustion air
inlet opening
2 Flue pipe outlet
collar
