Weil-McLain GV90+, Руководство пользователя

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Part number 550-143-010/1021
49
GV90+
series
2
gas-fired water boiler – boiler manual
DIRECT EXHAUST — Boiler room air openings
Special considerations
Tight construction
ANSI Z223.1/NFPA 54 - latest edition defines unusually tight
construction where:
1. Walls and ceilings exposed to the outside atmosphere have a
continuous water vapor retarder with a rating of 1 perm or
less with openings gasketed, and . . .
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, be-
tween 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 openings into
the building from outside, sized per the appropriate case in Fig-
ure 60, page 50 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 un-
less all appliances are installed as direct vent. Always provide air
openings sized not only to the dimensions 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 during boiler
operation.
To accomplish this interlock, wire an isolated contact
(proving the
damper open) in series with the thermostat input to the boiler.
The boiler will not start if this contact is open, and will shut down
should it open during operation.
Combustion air provision
The GV90+ boiler can use inside air if no contaminants are pres-
ent in the boiler space. (If contaminants are likely to be present,
install the boiler as a direct vent appliance, using the appropriate
vent instructions in this manual.)
The boiler room must be fitted with combustion air openings large
enough to provide air for all appliances in the room. Use the fol-
lowing information to size the openings. Ensure the installation
complies with all applicable codes and standards.
Where the GV90+ boiler shares a space with other appliances, the
combustion air openings must be sized to handle the combined
requirements of all appliances in the space.
Sizing combustion 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 60, page 50 , selecting the appropriate installation
conditions.
Air openings must be sized to handle all appliances
and air movers (exhaust fans, etc.) using the air
supply.
The sizing given in Figure 60, page 50 is based on the National
Fuel Gas Code, ANSI Z223.1/NFPA 54 - latest edition, allow-
ing adequate air openings for gravity-vented gas appliances
(Category I) in addition to that needed for the GV90+ boiler.
The air openings recommended in Figure 60, page 50 will allow
adequate ventilation and combustion air provided the boiler room
is not subjected to negative pressure due to exhaust fans or other
mechanical ventilation devices.
Refer to the National Fuel Gas Code for dealing with other
conditions.
Free area — 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
sizing the air openings.