Advanced Valve Temp & Relief Group

Advanced Valve Temperature & Pressure Relief (T&P) Valves are critical safety components engineered for the automated protection of pressurized hot water systems, specifically high-pressure geysers and industrial boilers. Designed to prevent catastrophic tank failure, these valves act as a mechanical “fail-safe” by monitoring both internal temperature and static pressure, automatically discharging water if safety limits are exceeded.

Technical Specifications

• Material: High-grade DZR (Dezincification Resistant) Brass body.
• Pressure Rating: Typically available in 400kPa or 600kPa variants (system dependent).
• Temperature Trip Point: Set to discharge at 93°C to 99°C.
• Inlet/Outlet Size: Standard 20mm (3/4″) or 15mm (1/2″) BSP threads.
• Probe Type: Extended stainless steel or copper thermal element.
• Compliance: SANS 198 (South African National Standard) approved for insurance-compliant installations.

Key Performance Features

• Dual-Action Protection: Unlike a standard safety valve that only reacts to pressure, the T&P valve features a thermal probe. If your thermostat fails and the water approaches boiling point, the valve opens to prevent “superheated” steam explosions.
• DZR Brass Integrity: Specifically formulated to resist the corrosive effects of varying water qualities in the Gauteng region. This prevents the “seizing” of internal springs, ensuring the valve remains operational throughout the Winter 2026 season.
• Manual Test Lever: Features an integrated stainless steel lever that allows technicians to manually “crack” the valve to clear grit or lime-scale buildup without disconnecting the plumbing.
• Precision Spring Calibration: The internal stainless steel spring is factory-set to a specific kPa rating, ensuring it does not “weep” or drip under normal operating pressures while providing an immediate response during a surge.
• High-Flow Discharge: Designed with a high-capacity orifice to rapidly vent large volumes of water, quickly reducing the internal energy of the geyser during an emergency.

Professional Installation & Maintenance Tips

• Probe Submersion: CRITICAL. The thermal probe must be fully immersed in the top 15cm of the tank water where it is hottest. If installed too far from the tank (on a long pipe extension), it will not react in time to a temperature spike.
• Discharge Piping: The outlet must be piped to the outside of the building using copper piping (never plastic/PEX), sloped downward to prevent “air-locks.” This ensures that if the valve trips in April 2026, the boiling water is directed safely away from people and electrical equipment.
• The “Drip” Diagnosis: A slight drip usually indicates that your Advanced Pressure Control Valve is failing or that the expansion in the system is too high. A heavy, continuous flow suggests the T&P valve has been triggered by an overheating element or a faulty thermostat.
• Scaling Prevention: In areas with “hard” water, lime-scale can coat the thermal probe. Use the manual lever once every six months to flush the valve and ensure the seat is clear of debris.
• Thread Integrity: Use high-quality PTFE thread tape or Unitwist jointing compound. Do not over-tighten into the geyser flange, as this can distort the brass body and cause internal leaks.

Common Use Cases

• Residential Geysers: Mandatory safety equipment for all high-pressure electric and solar water heaters.
• Industrial Boilers: Secondary safety relief for pressurized hot water storage in workshops and site laundries.
• Solar Thermal Systems: Managing the extreme temperatures generated by solar collectors during high-UV Heidelberg afternoons.
• Commercial Kitchens: Protection for large-scale “Hydro-boil” units and industrial dishwashers.

Pro Tip: When replacing a T&P valve, always check the condition of the Anode inside the tank. If the valve has failed due to corrosion, your tank is likely at risk too. Keep your Kaufmann Spotlight handy during the install to inspect the threads for hairline cracks. For a professional finish, wipe the brass body with a Shield Microfibre Cloth to remove finger oils, which can lead to premature tarnishing in damp ceiling spaces.