Rinnai HDC 1600i Low NOX Installation And User Manual page 29

FLUE REQUIREMENTS
The flue must be installed by a competent, authorised person. It is the installer's
responsibility to ensure that the unit has been installed to all current local
requirements. Ensure that the flue terminal and hot water outlet connection cannot be
touched by children. The flue must be clear of obstructions and shrubbery.
Flues
The Rinnai HDC Condensing water heaters internal units may only be installed with the
approved Rinnai HDC flue kit provided. These instructions only apply to coaxial Rinnai
Flues. If in doubt contact Rinnai UK.
The required clearance of the flue terminal is shown on page 31.
When multiple units are installed together there must be enough clearance to satisfy the
requirements of the regulations. Under current regulations the heaters should have at least a
100mm clearance between them. The flue terminal should be over 2m from ground level
whenever possible. For lower installations a terminal guard cage must be installed.
Flue Length
Concentric flues: a single, coaxial, 80mm diameter inner pipe / 125mm diameter outer pipe,
flue system can be fit directly on top of the HDC.
The maximum flue length for coaxial flueing system is 15m total equivalent length. From total
equivalent length subtract 2m for each 90° bend (max 5 bends) and 1 m for each 45° bend.
There is no limit to the minimum length of the flue. Installations with total equivalent length of
flue >6m must alter the flue length Dip Switch (see page 40).
Split system: a special adapter must be first installed on top of
the appliance to bring the normal 80/125mm flue to a split
system flue diam. 80/80mm.
The maximum flue lengths are: air intake 5m total equivalent
length, 25m for exhaust.
From total equivalent length subtract 2m for each 90° bend (max
5 bends) and 1 mt for each 45° bend. There is no limit to the
minimum length of the flue. Installations with total equivalent
length of flue >6m must alter the flue length Dip Switch (see
page 40).
Common Header (Cascade) Flues
It is possible to connect this appliance into common header flue, cascade system.
For information on these installations contact Rinnai.
Separate instructions are provided with the flue system detailing the installation of the flue
components.
Always install a CO sensor in the boiler room and DO NOT install the water heater in an
area of negative pressure in case of B type common vent systems.
The drain pipe should be run in 22mm PVC, uPVC, or ABS pipe, copper is not
recommended. The drain pipe MUST be trapped.
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