BritTherm Replacement Pump Head H4 Series H4 25/6 (661996605)

The BritTherm H4 25/6 Replacement Pump Head is a versatile and energy-efficient clockwise-rotating motor head ideal for combination gas boilers. Designed with built-in PWM (Pulse Width Modulation) functionality, it allows seamless remote control of rotor speed via a low-voltage signal from the boiler’s electronic board. Compatible with leading thermostat brands such as Siemens and Honeywell, the H4 25/6 is a dependable solution for modern heating systems including underfloor heating, solar installations, and heat pumps.

Optimise your central heating system with the BritTherm H4 25/6, a reliable and easy-to-install replacement pump head built for clockwise rotor operation. This advanced motor uses PWM technology for remote speed adjustment and integrates directly with your boiler’s controller for smart, efficient operation.

The H4 25/6 is equipped with 11 automatic operating programmes and 3 constant-speed modes, giving it the flexibility to handle a variety of domestic heating requirements. Its energy-saving night mode reduces consumption to just 5 watts without sacrificing performance. Built-in thermal and electrical protection ensure long-term reliability, making this unit ideal for any homeowner or engineer seeking a robust, energy-conscious upgrade.

Features & Benefits:
✅ Clockwise rotation for compatibility with a wide range of boilers
✅ Integrated PWM for smart remote speed control
✅ Compatible with Siemens, Honeywell, and other thermostat systems
✅ Suitable for smart home, solar, and heat pump systems
✅ 11 automatic operation programmes
✅ 3 constant “Old School” speed settings
✅ Night Power Reduction Function (down to 5W)
✅ Built-in protection against electrical and thermal faults
✅ Easy to retrofit and install
✅ Boosts system efficiency and reduces energy bills
✅ Designed for modern heating system upgrades

• Programs = PWM Controlled Motor
• Maximum Head (Meters) = 6
• Flow (m3/h) = 3.2
• Power = 3~45
• Connection Size = 1”
• Energy Efficiency Index Rating (EEI) = EEI≤0.20
• Maximum System Pressure (KPA) = 10 Bar
• Protection Class = IP44
• Temperature Class = TF 95°C
• Insulation Class = F
• Material = -
• Supplied With (Loose in Box) = electrical cable 0.7 m long, pwm cable, Wilo power wire adaptor,Wilo PWM signal wire adaptor, fastening screws, data sheet and warranty instructions.

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