Combustion Air - Riello Array AR 3000 Installation And Operation Manual

Fig. 33 Exhaust located on side wall
− It is not recommended to terminate vent above any door
or window, condensate can freeze causing ice formations.
− Do not use chimney as a raceway if another boiler or fire-
place is vented into or through chimney.
− Because the unit is capable of discharging low temperature
exhaust gases, the flue must be pitched back towards the
unit a minimum of 1/4" per foot to avoid any condensate
pooling and to allow for proper drainage.
− While there is a positive flue pressure during operation, the
combined pressure drop of vent and combustion air sys-
tems must not exceed the following equivalent length:
−
PIPE SIZE - 8"
Model
MAX. equiv. MAX. equiv.
(m)
AR 3000 21
AR 4000 12
Fittings as well as pipe lengths must be calculated as part of the
equivalent length, according to the following table:
45° ELBOW - 8"
Model
equiv. (m) equiv. (ft)
AR 3000 1.5
AR 4000 1.5
90° ELBOW - 8"
Model
equiv. (m) equiv. (ft)
AR 3000 1.8
AR 4000 1.8
EXHAUST
BOILER
PIPE SIZE - 10"
MAX. equiv. MAX. equiv.
(ft) (m)
70 30
40 30
45° ELBOW - 10"
equiv. (m) equiv. (ft)
5 1.5 5
5 1.5 5
90° ELBOW - 10"
equiv. (m) equiv. (ft)
6 1.8 6
6 1.8 6
− For a natural draft installation the draft must not exceed -
0.25" W.C.
− These factors must be planned into the vent installation. If
the maximum allowable equivalent lengths of piping are ex-
ceeded, the unit will not operate properly or reliably.
− For Massachusetts installations, contact companies able to pro-
vide vent systems which conform to all applicable requirements
for installations within the Commonwealth of Massachusetts.
− For multiple boilers installation, common venting shall be sized
based on the data of Appendix M.

2.15 Combustion air

Air supply is a direct requirement of ANSI 223.1, NFPA-54, CSA B149.1
and local codes. These codes should be consulted before a perma-
nent design is determined.
Array boilers can take combustion air from the space in which are
installed, or the combustion air can be ducted directly to the unit.
Ventilation air must be provided in either case.
Material
ABS
PVC Schedule 40
CPVC Schedule 40
Polypropylene
Single wall galvanised steel
In cold climates it is essential to provide a motorized air inlet
damper to control the supply of combustion air and prevent nui-
sance condensation.
The combustion air must be free of:
− Permanent wave solutions;
− Chlorinated waxes/cleaners;
− Chlorine-based swimming pool chemicals;
− Calcium chloride
− Sodium chloride used for water softening;
− Refrigerant leaks;
− Paint or varnish removers;
− Hydrochloric acid/muriatic acid;
− Cements and glues;
− Antistatic fabric softeners used in clothes dryers;
− Chlorine-type bleaches, detergents, and cleaning solvents
found in household laundry rooms;
− Adhesives used to fasten building products and other sim-
ilar products.
(ft)
To prevent contamination do not connect the combustion air inlet
100
and exhaust near:
100
− Dry cleaning/laundry areas and establishments;
− Swimming pools;
− Metal fabrication plants;
− Beauty shops;
− Refrigeration repair shops;
− Photo processing plants;
− Auto body shops;
− Plastic manufacturing plants;
− Furniture refinishing areas and establishments;
− Remodeling areas;
− Garages with workshops
Whenever the environment contains these types of chemicals,
combustion air MUST be supplied from a clean area outdoors for the
protection and longevity of the equipment and warranty validation.
The more common methods of combustion air supply are outlined
in the following sections.
19
INSTALLATION
Standard
ANSI/ASTM D1527
ANSI/ASTM D1785 or D2665
ANSI/ASTM F441
ULC S636
26 gauge