Bespoke Heat Pump Systems Ltd
About Bespoke Heat Pump Systems Ltd
The transition from gas boilers to heat pumps opened gaps in the building services industry’s knowledge that neither the mechanical nor the controls professions currently fill. Bespoke Heat Pump Systems Ltd was founded to stand in those gaps.
Where the company began
In 2018, on a series of bespoke river source, ground source and air source heat pump projects — hydronic distribution systems delivering simultaneous heating and cooling, rather than packaged VRF/VRV refrigerant distribution systems — company founder Marc O’Brien watched the same two problems surface on project after project.
The first sat with controls. The BMS and audio-visual companies engaged to run these systems were not mechanically versed enough to take the plant into their scope, because what these systems demand is closer to machine control than to everyday BMS procedure such as the more familar plant monitoring, setpoint adjustment, enabling, disabling and alarm handling.
The second sat with the mechanical side itself. Consultants, mechanical contractors, OEMs and fitters had little idea how the heat exchangers, and the primary and secondary hydronic distribution, low loss header, buffer, thermal storage, variable speed pumps etc have to differ from the gas boiler systems they were brought up on.
Four years on, the industry caught up with the diagnosis. CIBSE’s applications manual AM17, produced with government backing specifically for heat pumps in larger non-domestic buildings, exists to raise awareness of the common issues behind ineffective installations. Contributors to CIBSE Journal’s heat pump coverage now say openly that many firms offering heat pumps lack the expertise, that systems are still sized by copying the outgoing boiler, and that the heat pump itself usually takes the blame for what are in fact design, controls and installation failures. As Roger Hitchin put it in CIBSE Journal: “Retrofitting a heat pump is not the same as replacing a boiler.”
BHPS Ltd describes it as three connected gaps.
Gap one — these are machines, and machines need machine control
A gas boiler barely notices its operating conditions: with combustion at some 2,000 °C serving water at 50–80 °C, capacity is all but indifferent to water temperatures (condensing-boiler returns aside). Vapour compression is different in kind. A heat pump loses capacity, compounding, at roughly 3.5% for every 1 K its source cools, and around 1% for every 1 K its delivery warms. Combine heat recovery chillers, water source heat pumps and peak winter supplimentary air source heat pumps in one plant and control stops being a matter of setpoints and time schedules. It becomes machine control: staged capacity with protective interlocks, flows held in balance either side of buffer vessels, return temperatures guarded within a few kelvin to keep upstream machines from prematurely unloading, cycling or tripping, and PI or PID constants that are necessary but can only be discovered empirically at commissioning by experienced observation.
Conventional BMS practice was never built for this — through no fault of BMS engineers. Their programming platforms are built with preconfigured HVAC libraries (multi-chiller sequencing, AHUs, FCUs etc) for primarily supervisory environments. No supervisory library block exists for a heat recovery chiller + water source + air source heat pump combination, because the facts and rules change with every project and every equipment selection. Nor do the manufacturers fill the space: OEM controllers protect the OEM’s own machine — rightly — but no manufacturer offers, or carries professional indemnity for, sequencing logic spanning a multi-vendor system. And in high-end residential work the same hole opens where AV and smart-home integrators, excellent within their own trade, are asked to command plant they cannot be expected to understand mechanically. None of this is a criticism of those trades: it is a scope that properly belongs to neither of them.
Gap two — hydronics designed for boilers quietly sabotage heat pumps
Because boilers tolerate almost anything, a generation of hydronic habits grew up that heat pumps punish. Low loss headers and buffer vessels that blend flow into return cost a boiler system little; with vapour compression the same mixing forces higher generation temperatures and compounds into real capacity and efficiency loss — and can drag a heat recovery machine below the return temperature it needs to survive. Idle heat exchangers left unisolated dilute loop temperatures. Flow imbalances across decoupling headers — harmless in a boiler system — must here be actively limited with PICVs and variable speed pumping. Even compressor loading rates on either side of a two-stage system need matching, especially at peak winter heating loads, or the interstage loop drifts away from its design band. None of this features in gas-era design habit, and it is precisely the knowledge the industry’s new guidance is trying to rebuild.
Gap three — a generation trained away from the fundamentals
For rather more than a full generation of industry entrants, VRF/VRV systems and their manufacturers’ application software did the selection work — mechanical, electrical and controls — for consultants and contractors. It was a reasonable reliance, and it worked. But it distanced the professions from bespoke controls development, from hydronic system design, and above all from the working knowledge of vapour compression that was once a foundational requirement. Now, with refrigerant regulation tightening through the F-gas phase-down, the market is migrating back toward hydronic systems, and the skills that migration demands were last commonplace a generation ago. OEMs discuss this openly among themselves: mechanical contractors and consultants are struggling to design and commission workable systems combining heat recovery, air source and water source machines. Independent analysis of the commercial heat pump “performance gap” reaches the same verdict — the shortfalls trace to system design, controls and integration, not to the machines themselves.
What Bespoke Heat Pump Systems Ltd does about it
BHPS Ltd was formed to hold both disciplines at once — the thermodynamics and hydronics on one side, the controls engineering on the other — so that clients, consultants, contractors, OEMs and BMS houses have one party fluent in the whole system.
An invitation
The deepest savings a heat pump system can offer lie in fully simultaneous heating-and-cooling heat recovery operation — which is exactly where all three gaps bite hardest. Each gap is cheapest to close early, at concept and schematic stage, and most expensive to close after commissioning has stalled. Whether you are a consultant or contractor with a hybrid heat pump plant to deliver, an OEM or BMS house needing the mechanical–controls bridge, or a client who simply needs the system to work as promised, Bespoke Heat Pump Systems Ltd was built for exactly this ground. Get in touch through the contact page.
The transition from gas boilers to heat pumps opened gaps in the building services industry’s knowledge that neither the mechanical nor the controls professions currently fill. Bespoke Heat Pump Systems Ltd was founded to stand in those gaps.
Where the company began
In 2018, on a series of bespoke river source, ground source and air source heat pump projects — hydronic distribution systems delivering simultaneous heating and cooling, rather than packaged VRF/VRV refrigerant distribution systems — company founder Marc O’Brien watched the same two problems surface on project after project.
The first sat with controls. The BMS and audio-visual companies engaged to run these systems were not mechanically versed enough to take the plant into their scope, because what these systems demand is closer to machine control than to everyday BMS procedure such as the more familar plant monitoring, setpoint adjustment, enabling, disabling and alarm handling.
The second sat with the mechanical side itself. Consultants, mechanical contractors, OEMs and fitters had little idea how the heat exchangers, and the primary and secondary hydronic distribution, low loss header, buffer, thermal storage, variable speed pumps etc have to differ from the gas boiler systems they were brought up on.
Four years on, the industry caught up with the diagnosis. CIBSE’s applications manual AM17, produced with government backing specifically for heat pumps in larger non-domestic buildings, exists to raise awareness of the common issues behind ineffective installations. Contributors to CIBSE Journal’s heat pump coverage now say openly that many firms offering heat pumps lack the expertise, that systems are still sized by copying the outgoing boiler, and that the heat pump itself usually takes the blame for what are in fact design, controls and installation failures. As Roger Hitchin put it in CIBSE Journal: “Retrofitting a heat pump is not the same as replacing a boiler.”
BHPS Ltd describes it as three connected gaps.
Gap one — these are machines, and machines need machine control
A gas boiler barely notices its operating conditions: with combustion at some 2,000 °C serving water at 50–80 °C, capacity is all but indifferent to water temperatures (condensing-boiler returns aside). Vapour compression is different in kind. A heat pump loses capacity, compounding, at roughly 3.5% for every 1 K its source cools, and around 1% for every 1 K its delivery warms. Combine heat recovery chillers, water source heat pumps and peak winter supplimentary air source heat pumps in one plant and control stops being a matter of setpoints and time schedules. It becomes machine control: staged capacity with protective interlocks, flows held in balance either side of buffer vessels, return temperatures guarded within a few kelvin to keep upstream machines from prematurely unloading, cycling or tripping, and PI or PID constants that are necessary but can only be discovered empirically at commissioning by experienced observation.
Conventional BMS practice was never built for this — through no fault of BMS engineers. Their programming platforms are built with preconfigured HVAC libraries (multi-chiller sequencing, AHUs, FCUs etc) for primarily supervisory environments. No supervisory library block exists for a heat recovery chiller + water source + air source heat pump combination, because the facts and rules change with every project and every equipment selection. Nor do the manufacturers fill the space: OEM controllers protect the OEM’s own machine — rightly — but no manufacturer offers, or carries professional indemnity for, sequencing logic spanning a multi-vendor system. And in high-end residential work the same hole opens where AV and smart-home integrators, excellent within their own trade, are asked to command plant they cannot be expected to understand mechanically. None of this is a criticism of those trades: it is a scope that properly belongs to neither of them.
Gap two — hydronics designed for boilers quietly sabotage heat pumps
Because boilers tolerate almost anything, a generation of hydronic habits grew up that heat pumps punish. Low loss headers and buffer vessels that blend flow into return cost a boiler system little; with vapour compression the same mixing forces higher generation temperatures and compounds into real capacity and efficiency loss — and can drag a heat recovery machine below the return temperature it needs to survive. Idle heat exchangers left unisolated dilute loop temperatures. Flow imbalances across decoupling headers — harmless in a boiler system — must here be actively limited with PICVs and variable speed pumping. Even compressor loading rates on either side of a two-stage system need matching, especially at peak winter heating loads, or the interstage loop drifts away from its design band. None of this features in gas-era design habit, and it is precisely the knowledge the industry’s new guidance is trying to rebuild.
Gap three — a generation trained away from the fundamentals
For rather more than a full generation of industry entrants, VRF/VRV systems and their manufacturers’ application software did the selection work — mechanical, electrical and controls — for consultants and contractors. It was a reasonable reliance, and it worked. But it distanced the professions from bespoke controls development, from hydronic system design, and above all from the working knowledge of vapour compression that was once a foundational requirement. Now, with refrigerant regulation tightening through the F-gas phase-down, the market is migrating back toward hydronic systems, and the skills that migration demands were last commonplace a generation ago. OEMs discuss this openly among themselves: mechanical contractors and consultants are struggling to design and commission workable systems combining heat recovery, air source and water source machines. Independent analysis of the commercial heat pump “performance gap” reaches the same verdict — the shortfalls trace to system design, controls and integration, not to the machines themselves.
What Bespoke Heat Pump Systems Ltd does about it
BHPS Ltd was formed to hold both disciplines at once — the thermodynamics and hydronics on one side, the controls engineering on the other — so that clients, consultants, contractors, OEMs and BMS houses have one party fluent in the whole system.
- System design guidance and review. Equipment and plant selection, schematic development and tracing, spreadsheet simulation of part-load behaviour, consultants’ specification appraisals made tangible for every stakeholder, project and commissioning schedules derived from those specifications, technical and specifications arbitration, and commissioning methods guidance and witnessing including factory acceptance tests and commissioning acceptance visits.
- Bespoke controls development. Sequencing and protection logic for multi-machine plant rooms: PLC/PFC control systems designed, built and commissioned, with predictive maintenance algorithms and the protracted commissioning-time reprogramming and empirical PID discovery these systems require. Ancillaries such as hydronic flow regulation, pressurisation and rainwater harvesting etc run under the same PLCs.
- Clean BMS and AV integration. BHPS Ltd does not provide BMS or AV services — it builds the machine-level control layer and hands the BMS or AV system installed by others read/write access to every equipment and plant room control point, over BACnet, Modbus or KNX, leaving supervision, scheduling, monitoring, alarms and energy reporting where they belong.
- Bespoke heat exchangers. River source heat exchanger example below - design guided by BHPS Ltd and built by one of London’s specialist heat exchange manufacturers.
- Training days for experienced HVACR and heat pump professionals. The kinetic theory of matter, vapour compression theory, psychrometrics, the physics of fans and pumps, and vapour compression system logging and log analysis — rebuilding exactly the foundations gap three describes.
- Wider renewables integration. Control functions extended onto solar thermal, solar PV, wind and wood, for full integration and optimisation of all sustainable energy sources — maximal renewable energy harvesting under one control scheme.
An invitation
The deepest savings a heat pump system can offer lie in fully simultaneous heating-and-cooling heat recovery operation — which is exactly where all three gaps bite hardest. Each gap is cheapest to close early, at concept and schematic stage, and most expensive to close after commissioning has stalled. Whether you are a consultant or contractor with a hybrid heat pump plant to deliver, an OEM or BMS house needing the mechanical–controls bridge, or a client who simply needs the system to work as promised, Bespoke Heat Pump Systems Ltd was built for exactly this ground. Get in touch through the contact page.
Bespoke River Source Heat Exchangers
Design guided by Marc O'Brien of Bespoke Heat Pump Systems Ltd and expertly built by one of London's specialist heat exchange manufacturers.
Heat Pump System Design Guidance
- Heat Pump Systems (associated plant room equipment & services) selection and design guidance.
- Systems commissioning methods guidance and witnessing.
- Consultant's specification appraisals and interpretations made tangible for all stakeholders.
- Project task and commissioning schedules all derived from the specifications.
- Technical and specifications arbitration services.
Controls for Plant Rooms and Renewables Integration
- Programable Logic Controllers (PLCs) and Programable Fieldbus Controllers (PFCs) for comprehensive plant room equipment control and monitoring with predictive maintenance algorithms.
- Control functions are easily extended onto other renewables such as Solar Thermal, Solar PV, Wind and Wood obtaining full integration and thorough optimisation of all sustainable energy sources.
- Pressurisation and rain water harvesting controls all also PLC managed.
Training Days for HVACR/HP Professionals
- The Kinetic theory of matter.
- Physics of Fans and pumps.
- Vapour compression theory.
- Psychrometrics.
- Vapour compression systems logging and log analyses.