andrews MAXXflo - FLUE SYSTEMS

MAXXo Water Heater
2020
FLUE SYSTEMS
e versatile ueing options will provide a solution to most
ushing requirements. e heater, when tted with
a concentric ue system, provides a room sealed
application. e concentric ue, supplied by Andrews,
is available for either horizontal or vertical installation
and the table below shows the basic kit supplied plus
optional extras. Alternatively, the heater can be tted with
a conventional ue system, which can be obtained from
a specialist ue stockist. A ue system suitable for a
condensing pressurised system must be specied.
e table and the concentric ue component below show
the maximum allowable length of ue for both systems.
e following pages show standard kits and additional
items for concentric ue supplied by Andrews. Horizontal
and vertical ue kits must be ordered separately. Flue kits
are not included in the heater price.
e ue system must be properly installed. Ensure
the inner ue is securely sealed at all the joints
otherwise incomplete combustion may result.
Do not exceed maximum ue lengths including
elbows.
GENERAL
Flue terminals must be installed in accordance with
BS 5440 and IGE/UP/10 to ensure the products of
combustion are properly dispersed. e drawing on page
27 shows minimum clearances for the ue terminals.
e ue terminal should be positioned where it will not
cause a nuisance from noise or from the combustion
products accumulating. Please contact Andrews technical
department if advice is needed for a particular installation.
See drawings on page 26.
We recommend that a condensate trap be tted when the
secondary ue length is over 1.5m.
If installed in a roof valley, the terminal should be at least
1m above the highest part of the roof structure and 2.5m
from any adjacent structure. e terminal must be tted
with a guard if less than 2m above ground level or in a
position where it may cause injury to persons resulting
from touching a hot surface. Guards can be ordered with
ue components. See table on pages 20 and 23.
Model CWH30 CWH60 CWH90 CWH120
Flue size (concentric) mm 80/125 80/125 130/200 130/200
Max. ue run – concentric (a) m 14 12 14 14
Max. ue run – conventional (b) m 50 20 50 40
Max. ue static pressure Pa 140 140 140 140
Max. ue gas volume m
3
/h 41 82 123 164
Max. ue gas temperature °C 52 52 52 52
(a) For a concentric ue/room sealed, reduce ue length by 1.2m for 90° bend, 0.7m for 45° bend and 1.5m
for condense trap.
(b) For a conventional ue, reduce ue length by 4m for 90° bend, 2m for 45° bend and 4 m for condense trap.
e different ventilation requirements for room sealed or conventional ue systems are given on pages 28 – 30.
SECTION 3 • INSTALLATION