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Cast Iron Condensing Boilers – Installation Manual
Torus Stainless Steel Condensing Boilers & Water Heaters – Installation Manual
If the boiler/water heater is operated while
the building is under construction it must be
protected from wood, concrete, sheet rock
and other types of dust. Failure to properly
protect the unit from construction dust will
damage the unit voiding the warranty!
Buildings will require the installation of a fresh air duct
or other means of providing make-up air if the intake
air option isn't used. Any building utilizing other gas
burning appliances, a fireplace, wood stove or any type
of exhaust fan must be checked for adequate
combustion air when all of these devices are in
operation at one time. Sizing of an outside air duct must
be done to meet the requirements of all such devices.
Never operate the Torus in an environment
subjected to a negative pressure unless it is
Direct Vented. Failure to comply with this
warning can result in excessive levels of
carbon monoxide causing severe personal
injury or death!
All Air From Inside The Building
If the boiler/water heater is to be located in a confined
space the minimum clearances listed in Table 1 must be
maintained between it and any combustible construction.
When installed in a confined space without the intake
air option two permanent openings communicating with an
additional room(s) are required. The combined volume of
these spaces must have sufficient volume to meet the
criteria for an unconfined space. The total air requirements
of all gas utilization equipment, fireplaces, wood stoves or
any type of exhaust fan must be considered when making
this determination. Each opening must have a minimum
free area of
1 in
2
/1000 Btu/hr, 2200 mm
2
/kW based on the
total input rating of ALL gas utilization equipment in the
confined area. Each opening must be no less than
100 in
2
,
64,516 mm
2
in size. The upper opening must be within
12
in, 300 mm of, but not less than 3 in, 80 mm from, the top
of the enclosure. The bottom opening must be within
12 in,
300 mm of, but not less than
3 in, 80 mm from, the bottom
of the enclosure.
All Air From Outside The Building
When installed in a confined space without the intake
air option two permanent openings communicating
directly with, or by ducts to, the outdoors or spaces that
freely communicate with the outdoors must be present.
The upper opening must be within
12 in, 300 mm of,
but not less than
3 in, 80 mm from, the top of the enclosure.
The bottom opening must be within
12 in, 300 mm of, but
not less than
3 in, 80 mm from, the bottom of the enclosure.
Where directly communicating with the outdoors or
communicating with the outdoors through vertical ducts,
each opening shall have a minimum free area of
1in
2
/
4000 Btu/hr, 550 mm
2
/kW of the total input rating of all
of the equipment in the enclosure.
Where communicating with the outdoors through hori-
zontal ducts, each opening shall have a minimum free
area of
1 in
2
/2000 Btu/hr, 1100 mm
2
/kW of the total
input rating of all of the equipment in the enclosure.
When ducts are used, they must have the same cross-
sectional area as the free area of the opening to which
they connect.
Table 2 - Make-up Air Duct Sizing
When calculating the free area necessary to meet the
make-up air requirements of the enclosure,
consideration must be given to the blockage effects of
louvers, grills and screens.
Screens must have a minimum mesh size of
1/4 in,
6.4 mm. If the free area through a louver or grill is not
known ducts should be sized per Table 2.
Direct Intake Air Option - General
This configuration provides combustion air directly to the
boiler/water heater air intake using a dedicated pipe
when using the direct vent option. Combustion air can
be drawn in horizontally through an outside wall or
vertically through the roof, see Figures 2, 3, 4 & 5. It
must be sized per Table 3.
Single wall galvanized smoke pipe, single wall aluminum
pipe, flexible aluminum pipe, PVC or CPVC pipe can be
used for the intake air pipe.
Table 3 - Intake Air Pipe Sizing
Required Cross Sectional Duct Area
Input
(MBH)
1/4 in, 6.4 mm
Wire Screen
Metal
Louvers
Wooden
Louvers
in
2
cm
2
in
2
cm
2
in
2
cm
2
1250
313
2019
416
2684
1250
8065
1500
375
2419
500
3226
1500
9677
2000
500
3226
667
4303
2000
12903
2500
635
4031
833
5382
2500
16127
3000
750
4838
1000
6452
3000
19354
4000
1000
6452
1334
8592
4000
25808
Model
Size
Pipe Diameter
in
Length
1250
6
80'
8
160'
1500
6
80'
8
160'
2000
8
160'
2500
10
160'
3000
10
160'
4000
12
160'
