11
3.0 OPERATING INSTRUCTIONS
CAUTION
Provincial and State regulations require that service mechanics must be
licensed to work on combustion equipment
.
The duct furnace should not be started or serviced by unqualified personnel.
Although many maintenance items do not require the service of a licensed mechanic,
it is recommended that a licensed mechanic supervise any work done on the duct
furnace by unlicensed personnel. Unqualified personnel should not be allowed to
work unsupervised.
•
Refer to the notes in section 1.0, at the beginning of this guide before continuing
•
Read the below sections before operating this furnace.
•
DO NOT attempt to start the burner if the duct furnace is full of vapor or
gas, or if the combustion chamber is very hot.
•
Before starting up the furnace, study and familiarize yourself with the wiring
diagram, sequence of operation, flame safeguard, controls, gas train, and burner.
3.1 Start-Up Check List
NOTE: When starting up the duct furnace for the first time or if the duct furnace has been
shut down for an extended period of time the same start-up procedures, as outlined in
sections 3.2 and 3.3, should be followed.
1. Set all electrical switches and main duct furnace disconnect switch to "OFF" position.
2. Close all duct furnace manual valves and field piping valves.
3. Check the duct furnace supply, discharge, and vent to make sure they are clear and
free from any obstructions. Check to make sure all applicable dampers are open or
adjusted to their correct settings.
4. Purge all the air from the gas lines per gas codes. Check all connections for leaks and
correctness. Ensure that the inlet pressure complies with the rating plate.
5. Inspect all electrical wiring, both field and factory installed, for loose connections.
Check all fuse blocks to determine that all fusing is installed.
6. Check all motor thermal overload settings against the rating plate figures.
7. Turn duct furnace disconnect switch "ON" (control switches are still "OFF") and check
the supply voltage. Voltage must be within 10% of nameplate rating. If not, consult the
electric utility company and have the voltage condition corrected before start-up.
8. Check set points of temperature limiting controls. Refer to the wiring diagram on the
duct furnace and set all temperature controls to the temperature settings indicated. The
safety operators for the furnace section setpoints are given below for most furnace
installations, however refer to the wiring diagram.
High Limit 200°F (93°C) & 210
°
F(99
°
C) -- Adjust Burner Air Switch To Field Conditions
Fan Switch 125°F (52°C) ON 90°F (32°C) OFF --Temperature Control Up To Customer
