HUD RULES FOR MANUFACTURED HOUSING

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Tankless Water Heater Installation Instructions

Where To Install

The tankless water heater should be installed as specified in the Federal Manufactured Housing Construction and Safety Standards (Standards). This was further clarified in a letter from HUD, dated Aug. 1, 2000.

In summary, the tankless water heater can be installed in any room, including closets, alcoves, utility rooms, and storage rooms, in which all walls and ceilings have a spread rating of 25 or less. Walls and ceilings consisting of unpainted or painted 5/16 inch or greater gypsum board or 5/16 inch or greater tape/textured gypsum board meet these flame spread ratings. When installed in such a room, the tankless heater can be mounted at any convenient location and without any additional enclosure.

If any of the walls or ceilings in a room have vinyl covered gypsum board, 5/16 inch or greater, the room may not meet the flame spread index of 25 or less, for the purpose of installing the tankless water heater. If one or more of the walls is paneling, the 25 or less flame-spread rating is not met. In these situations, the tankless water heater can be installed if a surrounding enclosure is constructed of 5/16 inch or greater gypsum. Vinyl covered gypsum board that is labeled with a flame-spread rating of 25 or less is acceptable to use in the water heater compartment without any additional enclosure.

Prevention of Storage

When the tankless water heater is installed in a closet, storage room or similar room, the area surrounding the appliance should be framed-in or guarded with noncombustible material such that the distance from the appliance to the framing or guarding is not greater than 3 inches. (When clearance required by the listing is greater than 3 inches, the guarding or framing shall not be closer to the appliance than the distance required by the listing.)

Clearance spaces surrounding the tankless water heater are not required to be framed or guarded when:

1. the space is specifically design for a clothes washer or dryer;
2. dimensions surrounding the appliance do not exceed 3 inches; or
3. the home manufacturer affixes either to the side of the storage area or closet containing the appliance, or to the appliance itself, in a clearly visible location, a 3"X5" adhesive backed plastic laminated label or the equivalent which reads as follows:

Warning
This compartment is not to be used as a storage area. Storage of combustible materials or containers on or near any appliance in this compartment may create a fire hazard. Do not store any materials or containers in this compartment.

All tankless water heaters shipped to Manufactured Home Builders will have a warning label as shown above on the exterior of the heater.

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