DN50 thermostatic valve HFT70002
The Legom HFT70002 DN50 Thermostatic Valve is a large-bore thermostatic mixing valve for commercial and industrial water heater installations requiring high-volume hot water delivery at a controlled safe temperature. With a G2 internal thread (DN50) connection and the same thermostatic mixing principle as the smaller HFT30001 series, the HFT70002 blends hot and cold water to deliver a preset mixed outlet temperature across a 20–60°C adjustment range, with a temperature control accuracy of ±2°C.
Manufactured from 57-3 copper with nickel plating and featuring a silk-screen ABS black handwheel, the HFT70002 operates across a working pressure range of 0.03–1 MPa with an ideal range of 0.1–0.5 MPa. Compatible with hot water inlet temperatures of 30–99°C, it suits electric, gas, solar thermal, and heat pump commercial water heating systems. As with the HFT30001 series, factory-preset temperature ranges (35–55°C, 40–50°C, 30–60°C) are available for OEM orders requiring restricted user adjustment.
Key Benefits
- DN50 G2 connection for high-flow commercial installations – The large 2″ bore handles the high volumetric flow rates of commercial water heating systems serving multiple simultaneous outlets — hotels, hospitals, apartment blocks, sports facilities, and industrial washrooms where smaller TMV sizes would create excessive pressure drop
- Temperature control accuracy of ±2°C – Consistent mixed water delivery within ±2°C of the set point regardless of fluctuations in hot or cold water supply pressure and temperature, providing reliable occupant comfort and safety at scale
- Adjustable from 20–60°C – The handwheel allows the system commissioning engineer to set the outlet temperature to match the application — lower for vulnerable user facilities, higher for industrial processes requiring warmer water
- No electricity required – Self-acting thermostatic operation driven entirely by the differential temperature of the hot and cold water supplies, with no electrical connection, controls, or power supply needed at the valve location
- 57-3 copper body with nickel plating – High-quality copper alloy construction with nickel surface treatment provides corrosion resistance and durability in continuous high-volume hot water service
- Wide pressure range of 0.03–1 MPa – Operates from low-pressure gravity-fed commercial systems through full mains pressure, covering the full range of commercial building water supply conditions
- Compatible with all commercial water heater types – Hot water inlet range of 30–99°C covers commercial electric storage, gas-fired, solar thermal, and heat pump water heater output temperatures
- Customizable preset temperature ranges – OEM orders can specify factory-preset ranges for applications requiring restricted operator adjustment
Technical Specifications
| Parameter | Specification |
|---|---|
| Model | HFT70002 |
| Body Material | 57-3 copper, nickel plated |
| Handwheel | ABS black silk-screen, 40mm |
| Connection | G2 internal thread (DN50) |
| Temperature Adjustment Range | 20–60°C (standard); 35–55°C / 40–50°C / 30–60°C (preset options) |
| Temperature Control Accuracy | ± 2°C |
| Working Pressure Range | 0.03 MPa – 1 MPa |
| Ideal Working Pressure | 0.1 MPa – 0.5 MPa |
| Cold Water Temperature Range | 5°C – 29°C |
| Hot Water Temperature Range | 30°C – 99°C |
| Primary Use | Commercial and industrial water heater systems |
HFT Thermostatic Valve Range — Size Comparison
| Model | Connection | Bore | Typical Application |
|---|---|---|---|
| HFT30001 | G1/2 | DN15 | Single fixture, small domestic heater |
| HFT30001 | G3/4 | DN20 | Standard domestic water heater |
| HFT70002 | G2 | DN50 | Commercial / industrial high-flow systems |
Application & Use Cases
- Commercial hotel and hospitality hot water systems – A central DN50 thermostatic mixing valve on the main hot water distribution riser serves all guest rooms and facility outlets simultaneously, ensuring safe delivery temperature across the entire building from a single point of temperature control
- Hospital and healthcare facility hot water – Large healthcare facilities require precise, consistent temperature control in high-volume hot water systems serving patient bathrooms, clinical washrooms, and sterilization support areas — applications where the ±2°C accuracy of the HFT70002 provides both safety and compliance
- Apartment building and residential complex hot water – Installed on the main hot water supply in multi-apartment buildings where a single central valve controls delivery temperature for all residents, with the storage system running at high temperature for Legionella control and the HFT70002 blending to safe delivery temperature
- Commercial solar thermal systems – Large-scale solar thermal installations in schools, hotels, and sports facilities where solar collectors can drive storage to very high temperatures during peak periods, requiring a large-bore TMV to handle the full building hot water demand while limiting outlet temperature
- Industrial washroom and process hot water – Food processing, manufacturing, and industrial facilities requiring large volumes of precisely temperature-controlled hot water for hygiene wash stations, process support, and worker welfare facilities
- Sports and leisure facilities – Swimming pool changing rooms, sports centres, and gym facilities with high simultaneous shower demand requiring large-bore TMV capacity to serve multiple simultaneous outlets without temperature variation
Installation Notes
- The HFT70002 is a large and heavy valve — ensure the pipework supports and valve bracket are rated for the valve’s weight plus the weight of water in the connected pipework before installation
- Connect hot water supply to the hot inlet (H), cold water supply to the cold inlet (C), and mixed water outlet (M) to the building hot water distribution pipework
- G2 internal thread connections require male G2 fittings. Use appropriate thread sealant rated for hot water service on all connections
- Install isolation valves on both hot and cold inlets upstream of the HFT70002 to enable valve servicing and cartridge inspection without shutting down the entire building hot water supply
- Install a strainer on the cold water inlet upstream of the valve to protect the thermostatic cartridge from grit and debris in the mains water supply
- The valve functions correctly across the full 0.03–1 MPa range but performs optimally at 0.1–0.5 MPa. At very high flow rates, verify that the pressure drop across the valve remains within acceptable limits for the system design
- After installation and before commissioning, flush all supply lines to remove debris. Set the handwheel to the required delivery temperature and verify outlet temperature at the furthest fixture using a calibrated thermometer before signing off the installation
- Commission and test the valve with a qualified plumber or HVAC engineer experienced in large-bore thermostatic mixing valve installation and commissioning
Frequently Asked Questions
Why use a central DN50 TMV rather than individual TMVs at each fixture?
Both approaches have valid use cases. A central DN50 TMV provides a single point of temperature control for the entire building, reducing installation cost and maintenance points compared to individual TMVs at each fixture. It is the preferred approach when the building code or project specification requires centralized temperature limiting. Individual fixture TMVs are used where point-of-use temperature control is required — for example, in healthcare facilities where individual outlet TMVs provide the final protection level — and may be used in combination with a central TMV for multi-level protection in high-risk applications.
How does this differ from the HFT30001 G1/2 and G3/4 models?
All three models use the same thermostatic mixing principle with identical temperature adjustment range (20–60°C), accuracy (±2°C), pressure range (0.03–1 MPa), and fluid compatibility. The difference is entirely in connection size and flow capacity. The HFT70002 DN50 G2 is designed for commercial and industrial systems requiring the high volumetric flow rate that its large 2″ bore enables — a flow capacity many times greater than the DN15 or DN20 models. Choose the HFT70002 when the system’s peak simultaneous hot water demand cannot be met by smaller valve sizes without excessive pressure drop.
What maintenance does the HFT70002 require?
The thermostatic cartridge should be inspected at least annually in commercial installations. Scale buildup on the cartridge in hard water areas can reduce temperature accuracy or cause sticking. The strainer on the cold inlet should be cleaned periodically — quarterly in high-sediment supply water, annually in clean mains supply. Full cartridge replacement should be considered every 3–5 years in continuous high-volume commercial service. Contact the Legom team for cartridge replacement specifications for the DN50 model.
Can the temperature adjustment range be restricted for commercial safety requirements?
Yes. OEM and project orders can specify a factory-preset temperature range of 35–55°C, 40–50°C, or 30–60°C that mechanically limits handwheel travel, preventing unauthorized adjustment above the preset maximum. This is a common requirement in healthcare, aged care, and education facilities where building codes or duty-of-care obligations restrict hot water delivery temperature. Contact the Legom team to specify the required preset range and any additional tamper-proof requirements for your project.
OEM & ODM Customization
Legom supports OEM and ODM services for the HFT70002 DN50 Thermostatic Valve. Customization options include preset temperature range, connection size, body finish, and handwheel design. All customization projects are handled with strict confidentiality. Contact us via WhatsApp or info@legomsmart.com.
Product information last reviewed by the Legom Technical Team. For the most current specifications, refer to the official datasheet or contact our sales team.
Custom OEM & ODM Solutions
Legom is a direct manufacturer offering end-to-end OEM and ODM services. With our in-house engineering and production capabilities, we work closely with distributors and system integrators to deliver fully customized solutions under strict NDA.
