Operating Foam System -706880080

TM 5-4210-233-14&P-1

2-13. FIREFIGHTING OPERATIONS-Continued

NOTE

Priming the pump may be necessary under some conditions

because of air trapped in the piping. Some fire departments

prime their pumps whenever pumping from water tank as a

general policy.

(4) Turn RELIEF VALVE lever to ON position and rotate INCREASE/DECREASE knob to obtain

desired pump output pressure.

(5) Open DISCHARGE valves and accelerate engine with THROTTLE control on pump panel to

obtain desired discharge pressure and capacity.

CAUTION

Monitor engine coolant temperature. If the temperature exceeds

210 deg. F (99 deg. C), or the alarm sounds, open ENGINE

COOLER control valve gradually until temperature stabilizes at

200 deg. F (93 deg. C). Failure to heed this caution may cause

engine damage.

f. Operating Foam System.

(1) Engage and prime the pump as described above.

(2) Open eductor valve (labeled WATER on pump panel).

(3) Rotate METERING VALVE handle to desired setting.

(4) Open FOAM valve.

(5) Open desired DISCHARGE valve(s) and nozzle(s).

NOTE

Residual pressure (as indicated by VACUUM gauge) must not

exceed 10 psi (69 kPa) when pumping from hydrant or relay

during foam operations.

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