HZT-6543002 / HZT-5779210 / HZT-5435015 / HZT-6542451 / HZT-6542958 Discharge Valve for Marine Vacuum Toilet Systems

HZT Discharge Valve Series – Marine Vacuum Toilet Spare Parts

The HZT discharge valve series includes multiple discharge valve references widely used in marine vacuum toilet systems, such as:

• HZT-6543002 – Discharge valve for Optima 3 configuration
• HZT-5779210 – Drain / discharge valve
• HZT-5435015 – Drain / discharge valve
• HZT-6542451 – Drain / discharge valve
• HZT-6542958 – Discharge valve reference

These discharge valves are responsible for controlling the waste discharge phase during the flushing cycle, releasing waste into the vacuum pipeline and ensuring stable operation of marine sanitary systems.

If you are searching for marine vacuum toilet discharge valve, vacuum toilet drain valve, or any of the above part numbers, this page covers the full HZT discharge valve spare parts group.

Function Description – What a Discharge Valve Does

In a marine vacuum toilet system, flushing performance depends on correct sequencing between:

1. rinse water admission (water valve)
2. waste discharge into the vacuum pipeline (discharge valve)

The HZT discharge valve is the key component that opens and closes the discharge path during flushing. It helps to:

• Release waste from the toilet bowl into the vacuum line
• Maintain stable vacuum system operation
• Prevent backflow and maintain hygienic operation
• Support consistent flushing under continuous shipboard use

The discharge valve is typically driven by pneumatic control logic and works together with the control mechanism and water valve.

Main Discharge Valve References (HZT Codes)

Depending on toilet model and configuration, the discharge valve may be specified under different reference codes.

Common HZT discharge valve codes include:

• HZT-6543002 (Optima 3 discharge valve reference)
• HZT-5779210 (Drain valve)
• HZT-5435015 (Drain valve)
• HZT-6542451 (Drain valve)
• HZT-6542958 (Discharge valve reference)
• HZT-6542811 (Discharge valve – one plugged variant)
• HZT-6544801 (EVACINFLUX silent drain valve kit reference category, silent drain valve kit)

Note: selection depends on the installed toilet type and back plate assembly configuration.

Compatible Components (System Reference – HZT Codes)

A discharge valve is usually part of a complete pneumatic flushing control system.

Common compatible components in the same system include:

Pneumatic Control / Flush Logic

• HZT-5775500 – Control mechanism
• HZT-6542434 – Control mechanism reference
• HZT-6560674 – Control mechanism reference
• HZT-5778600 – Control mechanism air filter
• HZT-5821000 – Activator
• HZT-6541675 – Activator
• HZT-5860303 / HZT-6544996 / HZT-5900200 – Pneumatic push button references
• HZT-6541458 – Push button switch reference (where applicable)

Water Admission (Water Valve)

• HZT-5774002 – Water valve
• HZT-5774000 – Water valve
• HZT-6560680 – Water valve reference
• HZT-5980801 / HZT-5980800 – Water supply kit references
• HZT-5774400 – Water valve diaphragm
• HZT-5774150 – Water valve filter
• HZT-6543030 – Spare part kit for water valve

Back Plate / Interface Assemblies

• HZT-6542981 / HZT-6542983 – Back plate assembly references

Related Seals, Diaphragms and Internal Service Parts

For maintenance and overhaul of discharge valve assemblies and pneumatic flushing circuits, the following spare parts are often referenced:

Seals & Rings

• HZT-5430805 – O-ring
• HZT-3790009 – V-ring
• HZT-6541213 – Gamma ring
• HZT-5490590 – Casing gasket
• HZT-5430827 – Rubber gasket

Diaphragms / Membranes / Bellows

• HZT-551120 – Membrane
• HZT-6560678 – Diaphragm (Optima)
• HZT-6542455 – Membrane reference
• HZT-5435169 – Rubber diaphragm
• HZT-6543134 – Air valve membrane
• HZT-6541272 – Bellows
• HZT-6562653 – Hose diaphragm
• HZT-6562975 – Sleeve diaphragm for discharge reference
• HZT-5435181 – Rubber sleeve

Mechanical Seals

• HZT-6547044 – Mechanical seal
• HZT-5490580 – Mechanical seal

Valve Stem / Check Valve / NR Valve

• HZT-6545051 – Valve stem kit
• HZT-5959902 – Micro check valve
• HZT-6546052 – Mini-check valve
• HZT-6545052 – Mini check valve reference
• HZT-101100116 – Distributor with NR valve

Jet Carrier / Nozzle References (Flush Performance Control)

Flushing behavior can be influenced by jet carrier selection and nozzle components, commonly referenced as:

• HZT-5430834 – Ejector nozzle
• HZT-5778000 – Jet carrier 30
• HZT-5778001 – Jet carrier 40

Pipes, Hoses and Connection Parts (Installation & Service)

Common connection references in marine vacuum toilet systems include:

• HZT-5433572 – Connecting sleeve
• HZT-5779400 – Sleeve coupling
• HZT-5779500 – Sleeve support
• HZT-5736324 / HZT-5481100 / HZT-5736322 / HZT-5470214 / HZT-5481150 / HZT-5736316 / HZT-5481004 – Hose references
• HZT-5433594 – Hose clamp
• HZT-5805900 – Hose to push button

Outlet / flushing ring references:

• HZT-6541025 – Flushing ring assembly
• HZT-6541056 / HZT-5434562 – Outlet pipe references
• HZT-5430670 – Flap
• HZT-5511500 / HZT-5433583 – Elbow / elbow joint references

Recommended Spare Part Kits (Service Packages)

For fast onboard servicing and planned maintenance, typical kit references include:

• HZT-5881000 – Spare part kit
• HZT-6541708 – Spare part set ES
• HZT-6545041 – Recommended spare parts kit

Typical Applications

HZT discharge valves are suitable for:

• Commercial vessels
• Passenger ships and ferries
• Offshore platforms
• Ship repair yards and marine service projects
• Marine vacuum toilet spare parts replacement and inventory stocking

Technical Notes (Important for Ordering)

Because discharge valve references may vary by toilet configuration and back plate assembly, we recommend confirming:

• installed discharge valve code (if available)
• installed back plate assembly reference
• photos of the valve and pneumatic connections

If you send photos or the onboard spare parts list, we can assist in selecting the correct discharge valve reference (HZT-6543002 / HZT-5779210 / HZT-5435015 / HZT-6542451 / HZT-6542958) and the related service parts.