Buy 802841 - Genuine Bendix R-12 Air Brake Relay Valve - 1 - wisentpartscenter.com

Description

Genuine Bendix BW802841 R-12 Air Brake Relay Valve is used in heavy-duty air brake systems to speed up brake application and release by controlling air flow close to the brake chambers. Instead of routing full brake-delivery air all the way from the foot valve, the R-12 uses a smaller control signal to open and close local reservoir air near the axle. Bendix describes the R-12 as a relay valve normally mounted near the brake chambers it serves.

Key Functions
- Relays control pressure from the foot brake valve to the service brake chambers.
- Speeds brake application by supplying air from a nearby reservoir.
- Speeds brake release by exhausting chamber pressure locally.
- Provides predictable brake response through a specified 7.5 PSI crack pressure.

Fitment & Specifications
- Component Type: Air Brake Relay Valve
- Bendix Series: R-12
- Bendix Part Number: 802841
- Body Configuration: 2 Supply / 2 Delivery, horizontal
- Crack Pressure: 7.5 PSI
- Control Port: 1/4-18 NPT
- Supply Ports: 2 × 3/4-14 NPT
- Delivery Ports: 2 × 1/2-14 NPT
- Exhaust Port: 1/2-14 NPT
- Operating Temperature Range: -40°F to 200°F (-40°C to 93°C)
- Mounting: Four 0.96 × 0.40 in slots

Verify fitment with us before ordering to ensure the correct part for your application.

Purpose of the Part

The BW802841 acts as a remote-controlled brake valve. When the driver applies the service brakes, control air reaches the R-12 and causes it to deliver reservoir air directly to the nearby brake chambers. When the brakes are released, the valve exhausts that pressure locally, reducing response delay in long heavy-truck air systems.

Issue Symptoms / When to Replace

A failing relay valve can cause delayed brake application or release, air leakage at the valve, brakes that drag after the pedal is released, or uneven brake response between axles. Because leaking chambers, damaged air lines, foot-valve problems, or incorrect system plumbing can create similar symptoms, the surrounding air-brake system should be checked before replacing the relay valve.

Brand Information

Bendix develops and supplies air-brake charging, control, and safety components for medium- and heavy-duty commercial vehicles throughout North America. Bendix states that its valves are widely used by OE manufacturers and are engineered specifically to control air flow and release throughout commercial-vehicle air-brake systems. The R-12 is one of Bendix’s established relay-valve designs for service-brake applications.

Installation Notes

Depressurize the complete air system before removal. Match the 7.5 PSI crack pressure, port sizes, body orientation, and supply/delivery layout before installing the replacement valve.

How to Identify an OEM Part

A genuine unit can be identified by the Bendix manufacturer markings and 802841 part number on the valve identification.

Why Buy BW802841 from Wisent Parts

  • ⏱️
    Fast shipping
    Orders before 12PM EST ship same business day.
  • 🛡️
    180-day warranty
    All parts covered from delivery date.
  • ↩️
    Easy returns
    30-day returns.
  • ✅
    Verify fitment
    Send VIN/ESN and we’ll confirm.

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Warranty & Return Information
Warranty Information

Wisent Parts offers a 180-day warranty on all parts from the date of delivery. This warranty covers orders placed directly through our website. If a part fails during this period, we’re here to help - whether it’s a replacement, repair, or refund. For full details, refer to the Warranty page.

Return Information

Wisent Parts accepts returns within 30 days of delivery. All returns are subject to a restocking fee. To qualify, parts must be unused and in their original condition. For full return instructions and restocking fee details, please refer to the Returns page.