Cirrus Design
Section 7
SR22T
Systems Description
P/N 13772-005
7-41
P/N 13772-005
7-41
Drain valves at the system low points allow draining the system for
maintenance and for examination of fuel in the system for
contamination and grade. The fuel must be sampled prior to each
flight. A sampler cup is provided to drain a small amount of fuel from
the wing tank drains, the collector tank drains, and the gascolator
drain. If takeoff weight limitations for the next flight permit, the fuel
tanks should be filled after each flight to prevent condensation.
Fuel Selector Valve
A fuel selector valve, located at the rear of the center console,
provides the following functions:
• LEFT Allows fuel to flow from the left tank
• RIGHT Allows fuel to flow from the right tank
• OFF Cuts off fuel flow from both tanks
The valve is arranged so that to feed off a particular tank the valve
should be pointed to the fuel indicator for that tank. To select RIGHT or
LEFT, rotate the selector to the desired position. To select Off, first
raise the fuel selector knob release and then rotate the knob to OFF.
Fuel Pump Operation
Fuel pump operation and engine prime is controlled through the Fuel
Pump rocker switch located adjacent to the fuel selector valve.
To prevent over-priming, the system uses a lockout relay that only
allows HIGH BOOST/PRIME for engine start and operations at high
power settings. When the manifold pressure is less than 24 in-Hg and
engine RPM is greater than 500 RPM, pressing the HIGH BOOST/
PRIME limits the fuel pump to low-speed mode BOOST.
Selecting BOOST energizes the fuel pump in low-speed mode
regardless of engine speed or manifold pressure to deliver a
continuous 4-6 psi boost to the fuel flow for vapor suppression in a hot
fuel condition.
The fuel pump operates on 28 VDC supplied through the 5-amp FUEL
PUMP circuit breaker on MAIN BUS 2.
Original Issue
