GOLD CGs Gas-Fired Water Boiler — Boiler Manual

1e Prepare boiler location — air openings

Combustion air opening location and sizing requirements depend on the clearances around the boiler. Check the boiler placement compared to

Figure 1, page 7.

 

 

If all clearances are at least equal to Figure 1,

 

page 7, apply the sizing and placement of openings

 

given on pages 10 and 11.

 

If ANY clearance is less than Figure 1, page 7,

 

you must provide air openings sized and located

 

as shown in Figure 2, page 7. DO NOT apply the

 

sizing and location information shown on page 10

 

or 11. The Figure 2 air openings are required even if

 

the boiler is direct vented (outside air piped to the

 

boiler air intake as described in this manual). These

 

openings ensure adequate air circulation around the

 

boiler for cooling, even if the boiler does not use

 

inside air for combustion.

Combustion air options

mended in Figure 3 will allow adequate ventilation and combustion air provided the boiler room is not sub- jected to negative pressure due to exhaust fans or other mechanical ventilation devices. Refer to the National Fuel Gas Code for dealing with other conditions.

Louver allowance

The free area of openings means the area

after reduction for any installed louvers or grilles.

Be sure to consider this reduction when siz-

Special considerations

Tight construction

ANSI Z223.1 defines unusually tight construction where:

1.Walls and ceilings exposed to the outside atmo- sphere have a continuous water vapor retarder with a rating of 1 perm or less with openings gasketed, and . . .

Using inside air — direct exhaust vent

The CGs boiler can use inside air if no contaminants are present in the boiler space. If contaminants are likely to be present, install the CGs boiler as a direct vent appliance, using the appropriate vent supplement and the instructions in this manual.

Using outside air — direct vent

Combustion air can be ducted directly from outside to the CGs boiler air intake fitting. This method is defined as direct vent (also referred to as sealed combustion). Refer to the appropriate vent supplement and the instructions in this manual. Two options are available: sidewall or vertical direct vent. Each requires a special vent component kit.

Sizing air openings

Air openings provide for ventilation (as well as combustion air) to prevent overheating of the boiler controls and boiler space. Air is also needed for other appliances located in the same space.

Use Figure 3, page 11, selecting the appropriate installation conditions. Note that the sizing given in Figure 3 applies only to CGs installations with clearances no smaller than shown in Figure 1, page 7 of this manual. For smaller clearances, regardless of how the air openings are arranged, two openings providing free area of 1 square inch per 1,000 Btuh input of all appliances in the space are required.

Air openings must be sized to handle all appliances and air movers (exhaust fans, etc.) using the air supply.

The sizing given in Figure 3 is based on the National Fuel Gas Code, ANSI Z223.1, allowing adequate air opening for gravity-vented gas appliances (Category I). The CGs boiler is rated Category III or IV (pressurized vent), and has different requirements for combustion and ventilation air, reflected by the special sizing instructions given in Figure 3. The air openings recom-

2.Weather-stripping has been added on openable windows and doors, and . . .

3.Caulking or sealants are applied to areas such as joints around windows and door frames, between sole plates and floors, between wall-ceiling joints, between wall panels, at penetrations for plumbing, electrical, and gas lines, and in other openings.

For buildings with such construction, provide air open- ings into the building from outside, sized per the ap- propriate case in Figure 3 if appliances are to use inside air for combustion and ventilation.

Exhaust fans and air movers

The appliance space must never be under a negative pressure unless all appliances are installed as direct vent. Always provide air openings sized not only to the dimen- sions required for the firing rate of all appliances, but also to handle the air movement rate of the exhaust fans or air movers using air from the building or space.

Motorized air dampers

If the air openings are fitted with motorized dampers, electrically interlock the damper to:

Prevent the boiler from firing if the damper is not fully open.

Shut the boiler down should the damper close dur- ing boiler operation.

To accomplish this interlock, wire an isolated contact (proving the damper open) in series with the thermo- stat input to the boiler. The boiler will not start if this contact is open, and will shut down should it open during operation.

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Part number 550-110-260/0107

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Weil-McLain 550-110-260/0107 manual 1e Prepare boiler location air openings, Combustion air options, Special considerations