Theory Of Operation - Desa 125T Owner's Manual

The air pump forces air through the air line. The air is then pushed through the
The Fuel System:
nozzle. This air causes fuel to be lifted from the tank. A fine mist of fuel is sprayed into the combus-
tion chamber.
The motor turns the fan. The fan pushes air into and around the combustion chamber.
The Air System:
This air is heated and provides a stream of clean, hot air.
The Ignition System:
fuel/air mixture in the combustion chamber.
The Flame-Out Control System:
Combustion Chamber
Clean
Heated
Air Out
Fuel
Tank
VENTILATION
WARNING: Provide a fresh air
opening of at least three square
feet (2,800 square cm) for each
100,000 BTU/HR rating. Provide
extra fresh air if more heaters
are being used. The minimum
ventilation requirements must be
followed to avoid risks associated
with carbon monoxide poisoning.
Make certain these requirements
are met prior to operating heater.
Example: A 58.6 kw (200,000 Btu/Hr) heater
requires one of the following:
• a two-car garage door [4.88 meter (16 feet)
opening] raised 12.7 cm (5 inches)
• a single-car garage door [2.74 meter (9 feet)
opening] raised 20.3 cm (8 inches)
• two, 76.2 cm (30 inch) windows raised 38.1 cm
(15 inches)
4

THEORY OF OPERATION

The ignition control assembly provides power to the ignitor. This ignites the
This system causes the heater to shut down if the flame goes out.
Ignitor
Fuel
Nozzle
Filter
Air For Fuel
System
Figure 2 - Cross Section Operational View
www.desatech.com
Fan
Motor
Air Pump
Air Line
Ignition Control
To Burner
Assembly
Air For
Combustion
And Heating
Air Intake Filter
Cool Air In
Air Output Filter
Fuel
113170-01E