Baxi
The Baxi Assure HP55-4-1-PHMB is an air-source heat pump, introduced in 2019, offering 5 kW heating capacity at 55°C and an A+++ ErP rating.
The Baxi Assure HP55-4-1-PHMB is a domestic air-source heat pump designed for UK heating systems. This page provides a technical overview for gas and heating engineers, detailing key operational specifications, efficiency ratings, and physical characteristics. Homeowners researching the Assure HP55-4-1-PHMB will find comprehensive information regarding its performance and suitability for various property types. The unit is part of Baxi's Assure HP product family, introduced in 2019.
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Full technical specifications extracted from the manufacturer brochure. Empty sections are hidden.
The Baxi Assure HP55-4-1-PHMB, identified by GC number 7898258, was introduced in 2019 as part of the manufacturer's Assure HP product family. This air-source heat pump is designed for domestic heating applications across the UK. The available documentation, classified as marketing material, indicates specific performance metrics rather than a single nominal capacity. Engineers should note that the unit delivers a heating capacity of 5 kW when operating at a flow temperature of 55°C, and 4 kW when the flow temperature is 35°C. The maximum flow temperature achievable by the unit is 55°C, making it suitable for both underfloor heating and radiator systems, provided the system design aligns with these output capabilities.
Efficiency is a primary characteristic of the Assure HP55-4-1-PHMB. It achieves an ErP rating of A+++ for both 35°C and 55°C applications, signifying high seasonal performance. This rating is crucial for homeowners seeking to minimise running costs and for engineers designing compliant, energy-efficient systems. The absence of explicitly stated COP or SCOP values means performance should be assessed based on the ErP classification and the stated heating capacities at specific temperatures.
Acoustic performance is an important consideration for external installations. The Assure HP55-4-1-PHMB operates with a sound power level (LwA) of 48 dB. This measurement is taken at the source and is a key factor in determining compliance with local planning regulations and MCS-020 requirements for permitted development, which often mandate specific distances from neighbouring properties based on sound output.
While detailed information on refrigerant type, GWP, or charge is not provided in the current data, these are critical factors for F-Gas compliance and environmental impact assessments. Similarly, specific physical dimensions for the outdoor unit, electrical requirements, or hydraulic parameters such as minimum flow rates are not available. Installers should refer to the official Baxi installation manual for comprehensive technical data, including clearances, pipe sizing, and electrical connections.
The unit's introduction in 2019 positions it within the evolving landscape of UK heat pump technology. Its A+++ ErP rating and specified heating capacities provide a foundation for system design. For servicing and maintenance, engineers should consult Baxi's specific guidelines, although no service interval or annual steps are detailed in the extracted data. The information presented here is based on a medium confidence extraction from marketing materials; therefore, verification with official technical datasheets is recommended for all critical design and installation parameters.
Common questions from engineers and homeowners about the Baxi Assure HP55-4-1-PHMB.
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Specifications on this page are extracted from the manufacturer brochure. Always cross-check against the latest datasheet before commissioning or quoting. Last updated 30 April 2026.