Outdoor Water Heaters

These heaters are design certified for out- door installation. Heaters must not be installed under an overhang of less than three (3) feet from the top on the heater. Three (3) sides must be open in the area under the overhang. Roof water drainage must be diverted away from the heaters installed under overhangs with the use of gutters.

The point from where the flue products exit the heater must be a minimum of four (4) feet below, four (4) feet horizontally from or one (1) foot above any door, window or gravity inlet to a building. The top surface of the heater shall be at least three (3) feet above any forced air inlet, or intake ducts located within ten (10) feet horizon- tally.

4 foot
Minimum
	4 foot
	Minimum
4 foot
Minimum
3 foot
Minimum
10 foot	1 foot
10 foot	Minimum
Minimum
Forced Air Inlet

Fig. #8245

HIGH WIND CONDITIONS (Outdoor Units Only)

In areas where high winds are frequent, it may be necessary to locate the heater a minimum of 3' from high vertical walls, or install a wind break so the heater is not in direct wind current.

COMBUSTION AIR (Indoor Units Only) Air For Combustion And Ventilation

The heater must have both combustion and ventilation air. Minimum requirements for net free air supply openings are 12 inches from ceiling for ventilation and 12 inches from the floor for combustion air as outlined in ANSI Z223.1, and any local codes that may have jurisdiction.

CAUTION: Combustion air must not be contaminated by corrosive chemical fumes which can damage the heater. Measures must be taken to prevent the entry of corrosive chemical fumes to the combustion and ventilation air supply. Such chemicals include, but are not limited to, chlorinated and/or fluorinated hydrocarbons such as found in refrigerants, aerosol propellants, dry-cleaning fluids, degreasers, and paint removers. Other harmful elements may come from bleaches, air fresheners, or mastics. Vapors from these types of products can form corrosive acid compounds when burned in a gas flame. The resulting acid condensate can damage or substantially reduce the life of the heater. It may become necessary to provide outside air directly to the heater in order to avoid this problem.

a. All Air From Inside The Building:

Each opening shall have a minimum net free square inches as noted:

b. All Air From Outdoors:

When air is supplied directly from outside of building, each opening shall have a minimum net free square inches as noted:

NOTE: If louvers, grills or screens are used on the openings, obtain the net free area from their supplier or manufacturer. If the design free area of a louver is not known nor available, it shall be assumed that wood louvers will have 20-25percent free area and metal louvers will have 60-75percent free area as shown in Sec. 5.3.5 National Fuel Gas Code.