Ansul Fill Cap Indicator - 017633

The Ansul Fill Cap Indicator (P/N 017633) is a pressure-indicating fill cap used across Ansul's stored-pressure equipment, including the Red Line cartridge-operated extinguisher line and other Ansul pressurized tank assemblies. When the unit is pressurized, the indicator's stem protrudes visibly from the fill cap, giving an inspector an immediate, tool-free visual confirmation that the tank is charged and ready. At atmospheric pressure, the stem sits flush, signaling that the unit is not currently pressurized.

This passive visual check is especially valuable during routine monthly inspections across facilities with many units in service, since it lets an inspector confirm pressurization status at a glance rather than relying solely on a gauge reading or other verification method. As a fill cap, it is also the access point used during recharge to refill the tank with the correct agent before the unit is returned to service.

Confirm exact fitment with your equipment's part list before ordering, since Ansul uses several fill cap designs across its product lines.

• Monthly Visual Inspection: Check the indicator stem position to confirm pressurization status as part of the routine visual check required by NFPA 10 or NFPA 17A depending on the equipment type.
• Annual or Recharge Service: A certified technician inspects the fill cap and its seal during scheduled maintenance and replaces it if it shows damage, corrosion, or a seal that no longer holds pressure correctly.
• Recharge Access: During recharge, the technician removes the fill cap to refill the tank with the correct agent, then reinstalls and verifies the cap seats and seals properly before re-pressurizing.

What equipment does this fill cap fit?

This indicator fill cap is used across various pieces of Ansul stored-pressure equipment that use this fill cap design, including extinguishers in the Red Line family. Confirm exact compatibility with your specific unit's part list or with your Ansul distributor before ordering, since fill cap designs vary across Ansul's product lines.

How do I read the indicator?

When the tank is pressurized, the indicator stem protrudes visibly above the surface of the fill cap. When the tank is at atmospheric pressure, the stem sits flush. A protruding stem during a monthly check on equipment that should be pressurized is a normal, expected reading; a flush stem on equipment that should be charged is a sign the unit needs attention.

Can I replace this myself?

Replacing or removing a fill cap on pressurized fire suppression equipment should be performed by a certified fire equipment technician, since improper removal or reinstallation can affect the unit's ability to hold pressure correctly.