Roberts Gorden WHA XS Series Manuale Utente

Provide gas-fired unit heaters, designed and manufactured for 

indoor use. 

A.  Unit Heater
B.  Controls

A.  American National Standards Institute (ANSI) / Canadian

  Standards Association (CSA): Establish requirements applicable

  to construction, certification and installation of unit heaters.

    a.  Standard ANSI Z83.8 / CSA 2.6 “Gas Unit Heater and Gas- 

  Fired Duct Furnaces” (latest edition)

B.  IAS: Establishes requirements applicable to construction and

  certification of unit heaters.

    a.  Standard No.10-96 “Unit Heaters for Residential Use”    

  (latest edition)

C.  National Fire Protection Association (NFPA): Establishes fire

  prevention standards.

    a.  Article 54: National Fuel Gas Code (latest edition)

    b.  Article 70: National Electric Code (latest edition)

A.  Product Data: Provide data with dimensions, service 

connections, accessories, controls, electrical nameplate data and 

wiring diagrams.

A.  Training: Provide owner with verbal operating instructions as 

well as original manufacturer’s installation, operation and service 

manuals.

A.  Manufacturer Qualifications: Company specializing in 

manufacturing the products specified in this section (gas-

fired unit heaters) with a minimum of ten years documented 

experience.  Equipment shall be the standard product of the 

manufacturer and shall have complete catalogued data.

B.  Installer Qualifications: All installation and service of unit 

heaters must be performed by a contractor qualified in the 

installation and service of said products with proof of a 

minimum of three years documented experience.

C.  Factory Testing: Each unit heater shall be factory tested.  Testing 

shall consist of verification of correct operation of burners, 

manifold, control assembly and electrical components.

A.  Conform to ANSI Z83.8 / CSA 2.6, latest edition, and provide 

evidence that the unit heater and its control system have been 

found in compliance with these standards by a nationally 

recognized testing laboratory.

A.  The product shall have a manufacturer’s limited warranty of at 

least 24 months, subject to the manufacturer’s standard warranty 

limitations.

 

A.  COMBAT® by Roberts-Gordon UHA[X][S]-Series

A.  Unit: Gas-fired, power-vented unit heater 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:

  1.  Separated Combustion: A separated combustion unit shall    

  consist of an enclosed sealed burner box to which   

 

  combustion air is vented through a piece of internal flexible  

  air duct. This duct terminates at an exterior cabinet flange to  

  which a vent run to the outside of the heated space should be  

  attached.

  2.  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 a    

  vent box produced of 409 stainless steel.

A.  Casing and Components: Galvannealed steel panels, minimum 

20 gauge. All panels shall be lined with a minimum of 

3/8"(10mm) thick insulation.

B.  Access Door: Door shall be provided for easy service of all 

critical components.

C.  Finish: Standard finish is a heavy-duty white powder-coat.

D.  Louvers: The cabinet shall be equipped with horizontal louvers.  

Louvers shall be spring-held and adjustable for directing airflow.

A.  Heat Exchangers: For Models 30-125, heat exchanger tubes 

shall be of a six-pass design with 1.5" (38 mm) outer diameter 

[aluminized steel] [409 stainless steel] tube.  For Models 150-

400, heat exchanger tubes shall be of a four-pass design with 

1.75" (44 mm) outer diameter [aluminized steel] [409 stainless 

steel] tube.  Heat exchangers shall not be clamshell design.   For 

Models 150-400, the heat exchanger tubes shall be dimpled to 

provide efficient heat transfer. The tube plates shall be made of 

[aluminized steel] [409 stainless steel]. The tube supports shall 

be made of [galvannealed steel] [409 stainless steel].

B.  Burners: The burners shall be in-shot type, directly firing each 

heat exchanger tube individually. Burners shall be capable of 

burning natural gas or LPG.

C.  Gas Train: The gas train is constructed of black pipe and includes 

a single-stage gas valve. The valve provides the regulator, main 

gas and manual shutoff functions.