AR21828 | Gymatic 3/A “C” Unloader Valve, 3626 PSI

AR21828 Gymatic 3/A “C” Unloader | 3626 PSI, Adjustable Pressure Knob

The AR21828 is the Annovi Reverberi Gymatic 3/A “C” unloader, rated to 3,626 PSI (250 bar). It bolts onto the pump and controls pressure: when the trigger closes, it sends flow to its built-in bypass so the pump is not dead-headed, and when the trigger opens, full pressure returns.

The knob sets working pressure: lower for siding, wood and paint, full pressure for concrete and equipment. It is the replacement unloader for machines built with the Gymatic 3/A, the compact predecessor to the Gymatic 3/B.

Will It Fit My Machine?

• Replacing a Gymatic 3/A: match it to the part number or “3/A” marking on your old unloader.
• Pressure: your pump must be rated at or below 3,626 PSI, or the unloader set below the pump’s rating.
• Newer machines: pumps fitted with a Gymatic 3/B take the 3/B family instead (AR20242, AR20081, AR20082, AR20399).

Not sure which you have? Text a specialist at (505) 226-6061 with a photo of the old unloader and your pump tag, and we’ll confirm the match.

Good to Know

• The Gymatic is a trapped-pressure unloader: when the trigger is released, pump pressure drops to zero but the hose stays pressurized.
• Set the working pressure with a gauge at the pump outlet, and keep a thermal relief valve on the pump to protect it during long bypass periods.

AR21828 Specifications

• Model: AR21828 (Gymatic 3/A “C”)
• Max Pressure: 3,626 PSI (250 bar)
• Pressure Adjustment: Knob
• Bypass: Built in
• Body: Brass
• Weight: 3 lbs
• Brand: Annovi Reverberi

Shipping: Usually ships via UPS in 1 to 3 days.