User Guide
Table Of Contents
- Safe Installation, Use and Service
- APPROVALS
- General safety INFORMATION
- Introduction
- Installation Considerations
- Installation requirements
- Gas Supply Systems
- Gas Pressure Requirements
- Supply Gas Regulator
- Mixing Valves
- Water Piping
- Temperature-Pressure Relief Valve
- Filling the Water Heater
- Air Requirements
- Unconfined Space
- Confined Space
- Fresh Air Openings For Confined Spaces
- Outdoor Air Through Two Openings
- Outdoor Air Through One Opening
- Outdoor Air Through Two Horizontal Ducts
- Outdoor Air Through Two Vertical Ducts
- Air From Other Indoor Spaces
- Venting
- Gas Piping
- Sediment Traps
- Temperature Regulation
- For Your Information
- Periodic Maintenance
- Venting System Inspection
- Burner Inspection
- Burner Cleaning
- Air Shutter Adjustment
- Housekeeping
- Anode Rod Inspection
- Temperature-Pressure Relief Valve Test
- Periodic Removal of Lime Deposits From Tank Type Commercial Water Heaters
- Deliming Solvents
- Tank Cleanout Procedure
- Deliming Using Flo-Jug Method
- Draining and Flushing
- Service
- Leakage Test Points
- Water Piping Diagrams
- Commercial Water Heater Limited Warranty
18
OUTDOOR AIR THROUGH TWO HORIZONTAL
DUCTS
FIGURE 15. FRESH AIR FROM TWO HORIZONTAL DUCTS
The conned space shall be provided with two permanent
horizontal ducts, one commencing within 12 inches (300
mm) of the top and one commencing within 12 inches
(300 mm) of the bottom of the enclosure. The horizontal
ducts shall communicate directly with the outdoors. See
Figure 15.
Each duct opening shall have a minimum free area of 1
square inch per 2,000 Btu/hr (1100 mm
2
per kW) of the
aggregate input rating of all appliances installed in the
enclosure.
When ducts are used, they shall be of the same cross
sectional area as the free area of the openings to which
they connect. The minimum dimension of rectangular air
ducts shall be not less than 3 inches.
OUTDOOR AIR THROUGH TWO VERTICAL DUCTS
The illustrations shown in this section of the manual are
a reference for the openings that provide fresh air into
conned spaces only.
DO NOT refer to these illustrations for the purpose of
vent installation. See Venting (page 19) for complete
venting instructions.
FIGURE 16. FRESH AIR FROM TWO VERTICAL DUCTS
The conned space shall be provided with two permanent
vertical ducts, one commencing within 12 inches (300
mm) of the top and one commencing within 12 inches
(300 mm) of the bottom of the enclosure. The vertical
ducts shall communicate directly with the outdoors. See
Figure 16.
Each duct opening shall have a minimum free area of 1
square inch per 4,000 Btu/hr (550 mm
2
per kW) of the
aggregate input rating of all appliances installed in the
enclosure.
When ducts are used, they shall be of the same cross
sectional area as the free area of the openings to which
they connect. The minimum dimension of rectangular air
ducts shall be not less than 3 inches.
AIR FROM OTHER INDOOR SPACES
FIGURE 17. AIR FROM INDOOR SPACES