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Outsourced MCS Heat Pump Design
Complete technical heat pump design for installers.
- Last updated: September 2026
- Heat Loss Hub · For Installers
Heat Loss Hub provides complete outsourced heat pump system design for installers who want the technical design produced for a specific project.
You provide the property and survey information. We produce the agreed design package, which can include:
- Room-by-room heat loss calculations
- Whole-property design heat load
- Design flow temperature
- Heat pump sizing and selection
- Radiator and emitter sizing
- Underfloor heating requirements
- Pipework and hydraulic calculations
- Required system flow rates
- Cylinder and hot water design
- Schematics and design notes
- Installer-ready technical documentation
Heat Loss Hub works independently of manufacturers and merchants, so the design can be based on the property and system requirements rather than on the need to sell a particular product.
KEY TAKEAWAY
You remain the installer and retain responsibility for the installation, commissioning, certification and final compliance of the finished system.
SUBMIT A PROJECT FOR DESIGN
Send us the property and survey information for your project and we’ll confirm the design scope before work begins.
What Is Included in a Complete Heat Pump Design?
A complete heat pump design should do more than produce a single heat-loss figure and select a unit with a similar number on the badge. The heating system needs to work as one coordinated design.
Depending on the agreed scope, Heat Loss Hub can cover:
Room-by-Room Heat Loss
Each room is assessed individually so the system design is based on where the heat is actually required. This establishes:
- Room design heat losses
- Whole-property heat load
- Emitter requirements
- System design conditions
Design Flow Temperature
The intended flow temperature affects radiator output, underfloor heating output, heat pump efficiency, required water flow, pipework and heat pump performance.
It should therefore be part of the design from the start rather than something decided during commissioning.
Heat Pump Sizing and Selection
The proposed heat pump is checked against the property’s design load and the output the exact model can deliver at the required operating conditions.
The model number alone does not tell you whether the unit is correctly sized.
Radiator and Emitter Sizing
Existing and proposed emitters can be assessed against the room-by-room heat losses and chosen design flow temperature. This can include existing radiator assessment, replacement radiator sizing, towel rails, fan-assisted emitters and underfloor heating requirements.
Pipework and Hydraulic Design
Where included, the design can consider required system flow rate, pipe sizing, pressure loss, available pump head, minimum flow requirements, system water volume, hydraulic separation and buffer or volumiser requirements.
Hot Water and Cylinder Design
Domestic hot water should be considered as part of the system design. Support can include cylinder sizing, hot water demand, heat pump compatibility, coil suitability, reheat performance and plant-space constraints.
From Survey Information to Finished Design
The quality of the final design depends on the quality of the information provided at the beginning of the project.
You Provide
Depending on the property and service, this may include:
- Property address
- Architectural or floor plans
- Room dimensions
- Ceiling heights
- Wall, floor and roof construction
- Window and door information
- Existing radiator sizes and types
- Underfloor heating details
- Existing pipework information
- Proposed heat pump location
- Cylinder location
- Electrical information where relevant
- Survey photographs
- Survey videos
- Preferred heat pump manufacturer or model where applicable
We Produce
The agreed technical design can then include:
- Room-by-room heat-loss calculation
- Whole-property design load
- Design flow temperature
- Emitter schedule
- Heat pump sizing assessment
- Model selection support
- Flow-rate calculations
- Pipework and hydraulic requirements
- Hot-water and cylinder assessment
- Schematics
- Technical design notes
- Final installer documentation
The scope is agreed before design work begins.
Room-by-Room Heat Loss
A complete heat pump system design starts with the building. Whole-house shortcuts do not tell you whether individual rooms can be heated properly at the chosen flow temperature.
Room-by-room heat loss allows the designer to assess:
- Which rooms have the highest heat demand
- Whether existing emitters can be retained
- Which emitters need increasing
- Whether underfloor heating output is sufficient
- What design flow temperature is required
- What whole-property heat load the heat pump must meet
This calculation then feeds into the rest of the design.
Design Flow Temperature and Emitter Sizing
The heat pump and the emitters cannot be designed independently. A lower flow temperature can improve heat pump efficiency, but the radiators or underfloor heating must still provide enough output to meet each room’s heat loss.
The design therefore considers both sides together. For each room, the process can include:
- Required room heat output
- Existing radiator output
- Corrected radiator output at design temperature
- Replacement or additional emitter requirement
- Underfloor heating output
- Required design flow temperature
KEY TAKEAWAY
A single weak room can sometimes force the whole system to operate at a higher temperature. That is why emitter sizing should be part of the system design rather than treated as an installation-day decision.
Heat Pump Sizing and Model Selection
A heat pump should be selected against the actual project conditions. That means checking the exact model at the relevant outdoor design temperature, heating flow temperature and required heating output.
Where relevant, minimum modulation and part-load behaviour can also be considered.
KEY TAKEAWAY
A unit marketed as an 8kW heat pump does not necessarily deliver 8kW at every outdoor and water temperature. The property determines the required performance. The product is then checked against it.
If you already have a preferred manufacturer or product range, Heat Loss Hub can work within that preference where the equipment is suitable for the calculated design.
Pipework and Hydraulic Design
A correctly sized heat pump still needs the required water flow to reach the heating system.
Where hydraulic design is included, the calculation can consider:
- Heat output
- Design temperature difference
- Required water flow
- Pipe bore
- Water velocity
- Pressure loss
- Pump head
- Minimum heat pump flow
- System water volume
- Hydraulic separation
KEY TAKEAWAY
Buffers and volumisers should not be added automatically. They should be used where the system design shows a genuine need. Similarly, the size of the connection on the heat pump is not a pipe-sizing calculation — the system needs to be assessed as a complete hydraulic circuit.
Explore: Heat Pump Hydraulic Design Service
Hot Water and Cylinder Design
Cylinder selection should involve more than choosing a familiar litre capacity. The design can consider:
- Number of occupants
- Expected hot water use
- Bath and shower demand
- Required storage
- Cylinder coil
- Heat pump output during reheat
- Reheat time
- Available plant space
- Proposed storage temperature
The aim is to produce a hot-water system that works with the heat pump rather than simply connecting a heat pump to whatever cylinder happens to fit.
What Does the Final Design Pack Contain?
The exact contents depend on the agreed project scope. A complete package may include:
- Property and project information
- Design assumptions
- Room-by-room heat-loss report
- Whole-property design heat load
- Design outside temperature
- Design flow temperature
- Radiator or emitter schedule
- Underfloor heating requirements
- Heat pump sizing assessment
- Selected or assessed equipment
- Required water flow
- Pipework and hydraulic requirements
- Hot-water and cylinder assessment
- System schematic
- Technical design notes
- Revision information
- Supporting installer documentation
The purpose is to give the installer a clear technical basis for the system being installed.
What Remains With the Installer?
Outsourcing technical design does not transfer responsibility for the finished installation.
Heat Loss Hub Is Responsible For
The agreed design work within the scope of the project, such as:
- Heat-loss calculations
- Emitter calculations
- Equipment assessment
- Hydraulic calculations
- Hot-water design
- Schematics
- Design documentation
- Agreed design revisions
The Installer Remains Responsible For
- Accuracy of information supplied from site
- Customer relationship
- Final equipment procurement
- Installation workmanship
- Site-specific installation decisions
- Commissioning
- Certification
- Project compliance
- Ensuring the installed system matches the final approved design
KEY TAKEAWAY
The design is a technical input into the installation. The installer remains responsible for the finished system.
What Happens if Something Changes on Site?
Heat pump installations do not always go exactly as originally planned. Examples include:
- A radiator needs moving
- A different heat pump model becomes available
- The cylinder will not fit in the intended location
- The pipe route changes
- A room is altered
- Additional survey information becomes available
- Existing pipework is different from the survey information
- The customer changes part of the specification
Those changes can affect the design. If the installed system changes, the design should change with it.
Where changes are material, the design should be reviewed and the documentation revised before the altered system becomes the final installation. This is particularly important where a change affects:
- Heat output
- Design flow temperature
- Emitter capacity
- Hydraulic resistance
- Required flow rate
- Hot-water performance
- Heat pump selection
Can the Design Be Completed From Plans?
Yes, where the available drawings and project information contain enough detail. New-build and renovation projects can often be designed substantially from architectural plans, construction specifications, window schedules, floor build-ups, room dimensions and proposed heating layouts.
Additional information may still be required for plant locations, pipe routes, cylinder space, electrical routes, existing services and site-specific installation constraints.
Can the Design Be Completed From a Remote Survey?
In many cases, yes. Heat Loss Hub is developing a structured remote-survey process designed to improve the quality and consistency of information supplied before design begins.
A remote survey can potentially collect room dimensions, construction information, window and door details, radiator information, underfloor heating information, pipework details, heat pump location, cylinder location, electrical information, photographs and videos.
KEY TAKEAWAY
The objective is to reduce missing information and avoid unnecessary survey revisits.
One Project or Regular Design Support
You can use Heat Loss Hub for a single project — a difficult property, a complex heating system, an unfamiliar heat pump, a project your team wants independently checked, or temporary design overflow.
Or the service can become part of your regular workflow. Repeat projects work best when the survey and project-handover process is standardised so the information arrives in the same format each time.
If you need flexible support across different parts of the design process rather than a complete design package on every project, explore the Remote Design Programme.
Frequently Asked Questions
The exact scope is agreed for each project, but it can include room-by-room heat loss, emitter sizing, design flow temperature, heat pump selection, hydraulic calculations, cylinder sizing, schematics and supporting technical documentation.
Yes. Heat Loss Hub can provide the agreed technical design while your company remains responsible for the installation, commissioning, certification and finished system.
The installer remains responsible for their own certification obligations and the finished installation. Heat Loss Hub provides the agreed technical design service within the defined project scope.
Yes, where the proposed equipment is suitable for the calculated property and system requirements. If a preferred model does not meet the design conditions, this should be identified before installation.
Yes. Where plans contain sufficient information, they can form the basis of a heat-loss and system-design project. Additional information may still be required for construction details, plant locations or installation constraints.
Yes. Emitter design can include existing radiator assessment, replacement radiator sizing and underfloor heating requirements.
Yes, where hydraulic design forms part of the agreed scope. This can include required system flow rate, pipe sizing, pressure loss, minimum flow and pump-head considerations.
Yes. Cylinder and hot-water design can consider storage capacity, household demand, coil suitability and reheat performance.
If the change affects the technical design, the design should be reviewed. Material changes should be reflected in the final documentation rather than left as an undocumented site variation.
Yes, where revisions are required and fall within the agreed design support. The revised design should clearly identify the latest issue so the installer knows which information is current.
Yes. Support can range from individual projects to regular design work. For repeat projects, the aim is to create a consistent survey-to-design handover.
Installer-branded or white-label workflows can be discussed depending on the service and project requirements. Explore White-Label Heat Pump Design Services.
Need the Complete Design Produced for a Project?
Send us the project information and we can confirm the design scope required before work begins.
Whether you are dealing with one difficult installation or need regular technical design support, Heat Loss Hub can provide the design resource behind your installation business.
SUBMIT A PROJECT FOR DESIGN
Send us the property and survey information for your project and we’ll confirm the design scope before work begins.
Explore: Heat Pump Design for Installers