Lochinvar Copper-Fin II CX401, Designer'S Manual, Page: 12 / 32

10
L o c h i n v a r
D E S I G N E R
’
S G U I D E C O P P E R
-
F I N I I B O I L E R
6 1 5 - 8 8 9 - 8 9 0 0
Lochinvar
NOTE:
Venting of a
high efficiency
appliance into a
cold or
oversized
masonry
chimney can
result in
operational and
safety problems.
For this type of installation, it is best to use a
draft control for each water heater located
on the riser between the vent outlet and the
breeching - Location “A”. When this riser is
too short to permit the installation of a draft
control, locate a separate control for each
water heater on the main breeching as
illustrated in Location “B”. If, because of
general crowding or other reasons, neither
of these locations are possible, use a single
large control in the breeching between the
water heater nearest the chimney and the
chimney, as shown in Location “C”.
All draft readings are made while unit is in
stable operation (approximately 5 minutes
running time).
Masonry Chimney
A masonry chimney must be properly sized
for the installation of a high efficiency gas
fired appliance. Exterior masonry chimneys,
with one or more sides exposed to cold
outdoor temperatures, are more likely to
have venting problems. The temperature of
the flue products from a high efficiency
appliance may not be able to sufficiently
heat the masonry structure of the chimney to
generate proper draft. This will result in
condensing of flue products, damage of the
masonry flue/tile, insufficient draft and
possible spillage of flue products into an
occupied living space.
Carefully inspect all chimney systems during
the project design phase. If there is any doubt
about the sizing or condition of a masonry
chimney, it is prudent to reline the chimney
with a properly sized and approved chimney
liner system. Metallic liner systems (Type “B”
doublewall or flexible or rigid metallic liners)
are recommended. Consult with local code
officials to determine code requirements or the
advisability of using or relining a masonry
chimney.
Powered Sidewall Venting
This venting system uses a powered
vent cap assembly which pulls the flue products
out of the stack. The fan in the powered vent
cap generates a negative draft at the unit.
Combustion air is drawn from the mechanical
room (See Combustion and Ventilation Air
Requirements, page 6).
(FIG. 9) MULTIPLE UNIT BAROMETRIC
DAMPER INSTALLATION
(FIG. 10) POWERED SIDEWALL VENTING
(POWERED VENT CAP SHOWN)
NOTE:
Common venting
systems may be
too large when
an existing unit
is removed. Be
careful to resize
any common
venting system
when new
appliances are
installed or
existing
appliances are
replaced.