Combustion Research Omega II, Installation, Operating, Maintenance And Parts Manual

Omega II

®

 Installation, Operation & Maintenance 

Combustion Research Corporation 

Page 25 

GENERAL 

The requirements and practices described below are based 
on the National Electrical Code ANSI/NFPA No. 70 (current 
standard) and the Canadian Electric Code.  Although the 
requirements are uniform throughout the country, local 
electrical codes may deviate from the National Electrical 
Code and the Canadian Electric Code, therefore, local 
inspection authorities should be consulted regarding local 
requirements. 

WARNING 

ELECTRICAL SHOCK 

DANGER OF SEVERE INJURY 
OR DEATH 

Field wiring to the heater and vacuum exhauster must 
be connected and grounded in accordance with 
national, state, provincial, local codes and to the 
guidelines outlined in this manual. In the United States 
refer to the most current revisions to the ANSI/NFPA 
70 Standard and in Canada refer to the most current 
revisions to the CSA C22.1 Part I Standard.

BURNER ASSEMBLY 

Safety control circuits must be a two wire circuit with a 
separate earth ground, and have a nominal voltage not 
exceeding 125 volts.  A safety control or protection device 
must be connected so as to interrupt the ungrounded 
conductor.  Install a service disconnect within 3' of the 

OMEGA II 

®

 Burner Assembly

. 

The 

OMEGA II

®

 Burner Assembly

 shall be connected to a 

power supply branch circuit fused at not more than the 
value appropriate for the rating of any control or device 
included in the circuit. 

Each 

OMEGA II

®

 Burner Assembly

 electrical requirement 

is 1.8 FLA amps at 115V, 60 Hz.  The thermostat shall be 
installed on the hot (L1) side with a sufficiently fused 
electrical supply line.  

DO NOT RUN THE ELECTRICAL 

SUPPLY LINES DIRECTLY ABOVE THE REFLECTOR 
OR BELOW THE REFLECTOR - CLEARANCE TO 
COMBUSTIBLES MUST BE MAINTAINED.

NOTE:

  If any of the original wire as supplied with the 

appliance must be replaced, it must be replaced with wiring 
material having a temperature rating of at least 90°C. 

Field wiring having a minimum rating of at least 90°C shall 
be used and supply circuit wiring shall have a minimum size 
of 14AWG. 

Large enough wire must be used in connecting to the 

OMEGA II

®

 Burner Assembly

.  This is necessary for two 

reasons:  1) carrying capacity and 2) voltage drop.  The 
wire size necessary to provide carrying capacity without 
over heating is determined by electrical codes which 
specify a minimum wire size for the amperage used.  Most 

electrical supply problems are caused by voltage drop due 
to long runs, or low voltage supplied by the utility. 

The correct size wire should be carefully selected before 
the installation is made.  The first step is to establish what 
voltage will be supplied by the utility.  This will vary across 
the country and should be verified by the utility and by 
actual measurement of the supply voltage prior to 
installation.  The following chart shows maximum wire 
lengths which will keep the voltage drop to a minimum of 
10% at various currents at 115V.  Only copper wiring 
should be used.

WIRE LENGTH FOR 10% VOLTAGE DROP 

IN 

FEET - 115V 60HZ

COPPER WIRE SIZE 

AMPERES No.14  No.12 No.10  No. 

8 

15 

150 225 350 600 

20 

110 175 275 450 

25 90 

140 

225 

350 

30 75 

125 

150 

300 

35 - 

100 

135 

250 

40 - 

85 

125 

225 

45 - 

- 

110 

200 

50 - 

- 

- 

175 

When supplying single phase from a three phase system, 
use a suitably sized machine tool transformer to transform 
460V or 230V three phase to 115V single phase.  Under no 
circumstances use 277V single phase input. 

WARNING:  Do not use 277 volt. 

!