AR20400 | Gymatic 3/B Unloader Valve Adj Injector 3650 PSI

AR20400 Gymatic 3/B Unloader | 3650 PSI, Up to 5.5 GPM, Adjustable Chemical Injector

The AR20400 is the Annovi Reverberi Gymatic 3/B unloader for RK, RR and XM series pumps, rated to 3,650 PSI at up to 5.5 GPM. It bolts straight 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. No external bypass hose is needed.

The built-in chemical injector is adjustable: more for degreasing, less for pre-rinse.

What It Fits

• Pumps: Annovi Reverberi RK, RR and XM series.
• Flow: up to 5.5 GPM.
• Pressure: up to 3,650 PSI.
• Connections: 1/2 in. male NPT inlet, 3/8 in. male NPT outlet.

Not sure it fits? Text a specialist at (505) 226-6061 with your pump model and a photo of the old unloader and we’ll confirm.

How to Use the Injector

• The injector draws detergent only at low pressure. Switch to a low-pressure soap nozzle to pull chemical.
• Turn the injector adjuster to set the detergent ratio for the job.
• Flush it with clean water after each chemical job to prevent residue and blockages.

Good to Know

• This is a trapped-pressure unloader: when you release the trigger, pump pressure drops to zero but the hose stays pressurized.
• Set the working pressure with a gauge, and keep a thermal relief valve on the pump to protect it during long bypass periods.
• This is the unloader fitted to AR’s C2I pump packages. Prefer a fixed injector? See the AR20081 or AR20082. No injector needed? See the AR20242.

AR20400 Specifications

• Model: AR20400 (Gymatic 3/B)
• Max Pressure: 3,650 PSI
• Max Flow: 5.5 GPM
• Inlet: 1/2 in. male NPT
• Outlet: 3/8 in. male NPT
• Injector: Adjustable
• Bypass: Built in
• Body: Brass
• Max Water Temperature: 140°F
• Fits: AR RK, RR and XM series pumps
• Brand: Annovi Reverberi

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