BritTherm Replacement Pump Head H3 Series H3 25/8 (661996508)

The BritTherm H3 25/8 Replacement Pump Head is a high-efficiency, universal electric motor designed for use in modern combination gas boilers requiring anti-clockwise rotor rotation. Built for maximum compatibility and efficiency, this pump head is remotely controlled via low-voltage PWM signals from the boiler’s circuit board. Fully compatible with smart home systems, thermostats, and renewable energy setups, the H3 25/8 offers 11 automatic programmes and 3 constant-speed settings. It also includes night-time power reduction and advanced protection against electrical and thermal faults, making it a reliable upgrade or replacement solution.

The BritTherm H3 25/8 Pump Head is part of the versatile H3 Series, offering reliable and energy-efficient performance for modern gas boilers. Designed to rotate anti-clockwise, this replacement pump head integrates seamlessly into boiler systems using universal PWM (Pulse Width Modulation) technology. It accepts low-voltage control signals via a dedicated cable from the boiler’s electronic board, enabling smooth and efficient remote rotor speed management.

Ideal for smart heating systems, the H3 25/8 is compatible with major thermostat brands such as Siemens and Honeywell. It supports 11 automatic operation modes and 3 traditional fixed-speed settings, suiting a variety of system demands. The built-in Night Power Reduction function lowers energy consumption to just 5 watts without compromising heating quality. With integrated electrical and thermal protection systems, this pump head ensures long-lasting, reliable operation and safeguards against external damage.

Features & Benefits:
✅ Universal compatibility with modern gas boilers
✅ Anti-clockwise rotor rotation for accurate system integration
✅ Remotely controlled via PWM low-voltage signal
✅ Compatible with smart thermostats and controllers (e.g., Siemens, Honeywell)
✅ Ideal for underfloor heating, solar systems, and heat pumps
✅ 11 automatic operation programmes + 3 fixed-speed modes
✅ Built-in Night Power Reduction – consumes as little as 5W
✅ Energy-efficient without compromising heating performance
✅ Electrical and thermal protection ensures pump longevity
✅ Suitable for smart home and renewable energy systems
✅ Easy upgrade or replacement option for faulty motors

• Programs = PWM Controlled Motor
• Maximum Head (Meters) = 8
• Flow (m3/h) = 3.6
• Power = 3~65
• Connection Size = 2”
• Energy Efficiency Index Rating (EEI) = EEI≤0.21
• 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, Grundfos power wire adaptor,Grundfos PWM signal wire adaptor, fastening screws, data sheet and warranty instructions.

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