Manual background

FRESH AIR FOR

Example 2: Locating Heater in Confined (Closed) Area

COMBUSTION

 

 

 

 

 

NOTICE

 

AND

 

 

 

 

 

A confined area has an air volume of less than 50 cubic

 

VENTILATION

 

feet for each 1000 BTU/Hr input rating of all appliances

 

 

in the area (cubic feet equals length x width x height of

 

Continued

 

area). Include adjoining rooms only if there are no doors

 

 

 

between the rooms.

 

 

 

 

 

 

 

If you install this heater in a confined area, you must provide additional fresh air.

 

Ventilating Confined Area

 

This fresh air would come from an adjoining open area or outdoors.

 

 

 

 

 

 

 

WARNING

 

 

 

 

 

 

 

The adjoining open area must have enough fresh,

 

 

 

outside air ventilation to supply any appliance in that

 

 

 

area plus the confined area. Follow instructions under

 

 

 

Example 1: Locating Heater in Unconfined (Open) Area,

 

 

 

page 17 to make sure fresh air ventilation is adequate.

 

 

 

 

 

 

 

When ventilating to an adjoining open area, you must provide two permanent

 

openings: one within 12" of the ceiling and one within 12" of the floor on the wall

 

connecting the two areas. Follow the National Fuel Gas Code NFPA 54/ANSI

 

Z223.1. It lists fresh-air requirements for fuel-burning appliances.

Ventilation

Grills into

Closet for

Hot Water

Heater

12"

Ventilation Grills

Connecting Two Rooms to Meet Unconfined Space

12"

Recommended

Fresh Air Duct into Crawl Space in Furnace Area or in

Closet with Water Heater

Figure 15 - Ventilation Air from Inside Building

After providing ventilation between rooms, check for draft hood spillage (see Draft Hood Spillage Test, page 17). If draft hood spillage still occurs, provide more ventilation between rooms or provide permanent ventilation from outdoors. See Providing Permanent Fresh-Air Ventilation, page 18.

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Desa GVB50N, GVB35N installation manual Combustion, Ventilation, Fresh Air For, Continued