Roberts Gorden 100, 75, 125 service manual Critical Considerations

	SECTION 3: CRITICAL CONSIDERATIONS
SECTION 3: CRITICAL CONSIDERATIONS
3.1 Basic Information	• Must be installed in a manner which allows
UHD[X][S] heaters have automatic ignition burners	access to all serviceable components. See Page
for ON/OFF operation only.	6, Figure 3 for details.

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

anon-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.

The use of stainless steel heat exchanger is recommended when air inlet temperatures are below 40° F (4.4° C) or temperature rise is less than 40° F (22.2° C) as condensation may form on the heat exchanger resulting in corrosion that may shorten its life.

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 using shelf mounting brackets.(See Page 11, Figure 6 and Page 11, Figure 7 for details.)

•Drop rods must be a minimum of 3/8" diameter mild steel. Four suspension points (3/8" nuts) are located on top of the heater.

•May be suspended from above (See Page 10, Figure 5) or from wall brackets of sufficient strength to support the heater as listed in the Technical Data Table on Page 45, Section 16.2.

3.4 Minimum Required Installation Clearances

Clearances around the heater and vent must be as indicated on Page 6, Figure 3 and Page 14, Figure 8 to ensure access for servicing, and correct operation.

3.5 Ventilation

It is important to ensure that there is adequate air space around the heater to supply air for combustion, ventilation and distribution in accordance with local and national codes. See Page 12, Section 7.

3.6 Gas Supply

It is important that the gas supply pipe is sized correctly to provide the inlet pressure as stated on the heater data plate. The gas supply pipe and electrical connections must not support any of the heater's weight. See Page 20, Section 9.

3.7 Electrical Supply

A permanent 120 V /1 Ø/60 Hz electrical supply is required for the main electrical power. The heater also requires suitable controls in accordance with Page 22, Section 10.

3.8 Vent

Choose heater orientation to allow for proper location of the vent. Each heater must be fitted with a correctly sized sealed vent system.

If vented horizontally, no other appliance may be connected to the vent. See Page 12, Section 7.

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