Standard Heater Cut Off Valves - Blue Bird D3RE 2014 Driver's Handbook Manual

Standard Heater Cut Off Valves

Valves are provided in the heater piping to permit isolation of the heating circuit
from the engine coolant circuit. This is useful in case a leak occurs within the system,
or to restrict the flow of hot water through the bus during warm weather.
When Valves No. 1 and No. 2 in the diagrams below are closed, engine coolant is
prevented from circulating through the heaters. (This does not restrict circulation of
the engine cooling circuit, so it is safe to opeartate the engine with the valves closed.)
[CAUTION] Do not operate auxiliary heater or auxiliary coolant pump with
heater cutoff valves closed
DRIVER'S
HEATER
REAR
HEATER
Heater Circuit
FRT. HTR.
1
ENGINE
2
D3RE
ROUTINE OPERATION
.
valve no
1
2
Engine: Cummins
location
.
at front left side of engine
( )
supply
.
at rear left side of engine
( )
return
93