Horizontal sections of the flue vent system must be pitched back towards the boiler at ¼ inch per foot to avoid condensate pooling and allow for proper drainage. Venting may be horizontal, through the wall installation or vertical, through the roof installation. The vent system, including terminus, must be sized in accordance with the flue gas flow(s) and pressure drop(s) per Table 3.

 

Flue Gas

Comb Air

 

 

Flow,

 

 

Req.

Permissible

 

ACFM

Boiler Model

SCFM

∆P Thru

@40%X

 

@40%XS

Venting

 

SA

 

o

 

 

200oF

A60 F

 

TF-150

452

330

0.2” WC

(Max)

 

 

 

TF-200

603

441

0.2” WC

(Max)

 

 

 

TF-250

753

550

0.2” WC

(Max)

 

 

 

TF-300

904

661

0.2” WC

(Max)

 

 

 

Table 3 Boiler Draft

 

 

Note:

NFPA 54-2009 (ANSI Z223.1-2009) paragraph

12.7.3.3states, “The sizing of gas vents for Category II, Category III, and Category IV Appliances shall be in accordance with the appliance manufacturers instructions.”

WARNING:

Do not use a barometric damper with this boiler. This is a positive pressure system. The use of a barometric damper may cause flue gases to leak into the boiler room.

The boiler vent must not be connected to any portion of another vent system without consulting the vent manufacturer. The boiler shall not be connected to any part of a vent system serving a Category I or Category II appliance, nor shall a Category I or Category II appliance be connected to the vent system serving this boiler. Improper connection of venting systems may result in leakage of flue gases into building spaces.

7

Date: 8-4-2010

Revision: 0

Form: 2396

Note:

An existing masonry chimney may be utilized PROVIDING that the existing chimney is lined with Special Gas Vent material(s), primarily AL29-4C®. There are venting manufacturers that have these products available.

1.7.2COMBUSTION AIR AND VENTING REQUIREMENTS FOR CANADA

Canadian Standard CAN/CSA-B149.1-05, Natural gas and propane installation code specifies venting systems and air supply for appliances in Section 8. Paragraph 8.1.4 states “Air supply shall be provided in accordance with Clause 8.4 when either an appliance or a combination of appliances has a total input exceeding 400,000 Btuh”. Air supply is defined as combustion air, excess air, flue gas dilution air, primary air, secondary air, and ventilation air. The air supply requirements below are a summation of Clause 8.4 specific to the Triple- Flex boiler.

Air Supply Requirements per CAN/CSA- B149.1-05 for Appliances having an input exceeding 400 MBH.

Ventilation Air: an opening for ventilation air at the highest point that opens to the outdoors shall provide Ventilation of the space. The cross sectional area of this opening shall be at least 10% of the area required for combustion air, but in no case shall the cross-sectional area be less that 10 in2 (6500mm2).

Combustion Air: For combustion air where the air supply is provided by natural airflow from outdoors, in addition to the opening for ventilation air, there shall be permanent opening having a total cross-sectional free area of not less than 1 in2 for each 30,000 BTU/hr. (70 mm2 for each kW) of the total rated input of the boiler(s). The location of the opening(s) shall not interfere with the openings for ventilation air. Please refer to CAN/CSA-B149.1-05, Para. 8.4.4, for combustion air openings if there are natural draft, fan assisted or power draft assisted equipment in the space.

When an air supply duct is used to supply combustion air, it’s discharge opening shall be located where there is no possibility of cold air affecting steam or water lines or other temperature sensitive equipment.

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Bryan Boilers 250, Triple-Flex 150, & 300, 200 service manual Combustion AIR and Venting Requirements for Canada, Scfm