Roberts Gorden UHD[X][S][R] 250, UHD[X][S][R] 300 Manufactured Units, Clearances to Combustibles

SECTION 3: CRITICAL CONSIDERATIONS

SECTION 3: CRITICAL CONSIDERATIONS 3.1 Basic Information

UHD[X][S][R] heaters have automatic ignition burners for ON/OFF operation only.

3.2 Manufactured Units

Gas-fired, power-vented duct furnace with tubular heat exchanger. Units shall have a minimum of 82% thermal efficiency. The standard unit shall consist of a non-separated combustion design with an aluminized heat exchanger. Design and heat exchanger alternatives shall be offered as follows:

•Separated Combustion: A separated combustion unit shall feature an enclosed, sealed burner box. A piece of flexible air duct connects this burner box to a flange on the cabinet. Combustion air should be ducted from outside the heated space, with the ductwork connecting to the unit with the use of the flange.

•Stainless Steel Heat Exchanger: A stainless steel heat exchanger unit shall consist of heat exchanger tubes, heat exchanger tube supports, heat exchanger tube plates and vent box produced of 409 stainless steel.

3.5 Clearances to Combustibles

WARNING

Fire Hazard

Some objects can catch fire or explode when placed close to heater.

Keep all flammable objects, liquids and vapors the required clearances to combustibles away from heater.

Failure to follow these instructions can result in death, injury or property damage.

Clearances must be as indicated on Page 3, Figure 1. If clearances to combustibles are not indicated, then installation clearances apply.

Figure 1: Clearances to Combustibles

3.3Location and Suspension All models:

• Must be installed indoors.

• Must be installed on the positive pressure side of

the air circulation blower.

• Must be installed in a level position with

horizontal discharge.

• May be mounted on a shelf of non-combustible

material.

• May be suspended from above (See Page 8,

6"

(15 cm)

6" (15 cm)

6"

(15 cm)

31"* (79 cm)

Figure 3) or from wall brackets of sufficient

strength to support the heater as listed in the

Dimension Data Table on Page 37, Section 15.1.

• Must be installed in a manner which allows

access to all serviceable components.

See Page 3, Figure 1 for details.

3.4 Minimum Required Installation Clearances

Clearances around the heater and vent must be as indicated on Page 3, Figure 1 and Page 11, Figure 4 through Page 14, Figure 9 to ensure access for servicing, and correct operation.

Clearance to Vent: 2" (5 cm)

*31" (79 cm) minimum is necessary for servicing.

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