Description
Power Products 278614P DC-4 double check valve replaces Bendix 278614/278614N, Haldex KN25060, and Sealco 320100 in heavy-duty truck and trailer air-brake circuits. Two 3/8″ NPT supply ports feed a single 3/8″ NPT delivery, with internal shuttle that automatically selects the higher of the two source pressures and prevents backflow into the lower-pressure leg. Used wherever the system blends primary and secondary air supplies into a common downstream control circuit (e.g., service brakes, parking brake control).
Specifications
| Manufacturer | Power Products |
|---|---|
| Part Number | 278614P |
| Part Type | DC-4 Double Check Valve |
| Configuration | 2 Supply, 1 Delivery |
| Port Size | 3/8″ NPT (all three ports) |
| Application | Heavy-duty air-brake systems (truck, trailer, bus) |
Cross References
This valve replaces or is equivalent to the following part numbers:
- Bendix: 278614, 278614N
- Haldex: KN25060
- Sealco: 320100
- Velvac: 034062, 030031
- Euclid: ESL320100
- PAI: LCV4067, EM40670
- Tectran: WM80A
- Midland: RM8001X
- Protier: PT278614
- Fortpro: F224714
- Apsco: VS2R
- New Star: SA269
- World American: WA278614
- Also known as: A43912, EBN278614X, 72404-0001, 641564, 12267073, 20QE2222R, 20QE283R, 764368C92
Applications
This double check valve is used wherever two separate air supplies must feed a single downstream circuit on FMVSS-121 air-brake equipment:
- Tractor service-brake control circuit (primary + secondary air supply blending)
- Trailer parking-brake control where dual-source priority is required
- Two-way valve isolation between primary and secondary brake reservoirs
- Auxiliary air circuits combining tractor and trailer supplies
Verify port sizes and circuit layout before installation. All three ports are 3/8″ NPT female; orientation of the two supply ports vs. the single delivery is fixed by the valve casting.









