Regal 3300 Owner's Manual page 127

Typical Water Tank
The fresh water tank level is located under the cockpit floor. The
capacity is approximately 29 gallons. A feed hose connects the system
to the fresh water pump/strainer for distribution purposes. In cold
climates, use appropriate winterization procedures for entire water
system.
Typical Freshwater Pump
N OTT: The fresh water tank level should be topped off before
leaving the dock. Tnsure the water quality is potable
before filling the tank at the deck fill point.
To Fill Fresh Water System:
1. Unscrew the "water" fill deck fitting. Fill the fresh water tank with
approximately 29 gallons of fresh water with a suitable container or
hose. Make sure the water is safe for drinking.
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Systems
Feed Hose
Sender
Hold Down Strap
Pressure Pump
Outgoing Water
To Equipment
Water Filter
Incoming Water
From Tank
4-15