BritTherm Replacement Pump Head H4 Series H4 25/8 (661996608)

The BritTherm H4 25/8 Replacement Pump Head is designed for modern combination gas boilers requiring clockwise rotor rotation. Featuring built-in PWM technology, this motor allows precise remote control of rotor speed via a low-voltage signal from the boiler’s electronic board. Compatible with a variety of controllers and thermostats such as Siemens and Honeywell, it is ideal for integration into smart homes, underfloor heating, solar thermal, and heat pump systems.

Enhance your heating system with the BritTherm H4 25/8, a universal electric motor pump head designed for clockwise rotation in combination boilers. The motor’s integrated PWM processor facilitates remote speed control through the boiler’s electronic system, enabling smooth and efficient operation tailored to your home’s needs.

This pump head supports 11 automatic work programmes, including three constant fixed speeds for traditional setups. Its Automatic Night Power Reduction Function lowers energy consumption to just 5 watts during low-demand periods, contributing significantly to energy savings without compromising heating performance.

Robust electrical and thermal protection systems safeguard the pump against faults caused by external factors unrelated to its operation, ensuring reliability and long service life. This pump is perfect for heating engineers and homeowners aiming to upgrade or maintain efficient heating systems.

Features & Benefits:
✅ Clockwise rotor design for wide boiler compatibility
✅ Built-in PWM for seamless remote speed control
✅ Compatible with Siemens, Honeywell, and other thermostats
✅ Suitable for smart home, underfloor heating, solar, and heat pump systems
✅ 11 automatic operating programmes plus 3 fixed speed modes
✅ Automatic Night Power Reduction cuts energy use to 5 watts
✅ Electrical and thermal protection for enhanced durability
✅ Easy retrofit replacement for modern combination boilers
✅ Improves heating system efficiency and reduces running costs

• 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, Wilo power wire adaptor,Wilo PWM signal wire adaptor, fastening screws, data sheet and warranty instructions.

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