Model 30000-S DHPU Manual
Rev. 0
JRK
17SEP12
Page 16
Safety Features
The power unit is equipped with several safety features, which are explored in more detail in
the following sections.
Engine Silencer
The exhaust from the engine is routed through a silencer (muffler) to reduce the engine
noise. See the location of the silencer in the picture below.
Engine Spark Arrestor
After the silencer, the exhaust is routed through a spark arrestor. The spark arrestor, as
seen below, uses centrifugal force to separate solids from exhaust gas. The manufacturer
recommends inspecting and cleaning out the spark arrestor every 1000 operating hours or
three times per season, whichever time period is less. The inspection should include a visual
check for holes, cracks or metal corrosion. If any of the above conditions are found, then
replace the spark arrestor. Also, ensure the mounting clamp is securely tightened.
The spark arrestor and exhaust are wrapped with a thermal blanket to help prevent the
operator from accidentally touching the unit during operation. This area should not be
touched even though it contains this safety precaution.
DO NOT SET TOUCH THE EXHAUST SYSTEM COMPONENTS DURING OPERATION OF
THE POWER UNIT AS IT HEATS UP TO DAMAGING TEMPERATURES. THIS HEAT IS
RETAINED EVEN AFTER THE POWER UNIT IS TURNED OFF. VERIFY THE UNIT IS COOL
BEFORE WORKING AROUND THE EXHAUST SYSTEM.
Figure 9: Engine Exhaust Components and Over Speed Shutdown
Over Speed Shutdown
If the unit over speeds during a runaway condition such as the intake of gas, then the unit
will automatically shut down when the speed exceeds the factory setting of 2400 RPM. The
engine should not be restarted again until the area is declared safe for operation. The
location of the over speed shutdown is shown in the previous photo. For maintenance and
setting instructions, review the over speed shutdown manual.
