Pierce HUSKY 12 GPM, Operation & Maintenance Manual

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GENERAL
2-10 / Husky 12 Foam System
© 2017 Pierce Manufacturing Inc. All Rights Reserved.
2-2.3a Manifold and Master Drains
Figure 2-12: Manifold & Master Drains
1066/1067
The manifold drains are used to bleed off pressure/water anytime the water pump has been pressurized (after the
water pump is shut off). If a dry water pump condition is desired, leave manifold drains open until the fire scene is
reached.
The master pump drain will empty both the discharge and inlet manifolds of water when opened. The water pump
drain should be pulled (opened) daily.
2-2.3b In-line Water Check Valve
Figure 2-13: In-line Water Check Valve
1014
The In-line Water Check Valve prevents foam from entering the water pump and the remainder of the water system.
It is installed in the water piping, before the foam injection manifold and the water flowmeter.