Answer first
Ask for the room-by-room heat-loss calculation, emitter schedule, design temperatures, selected-unit capacity, estimated seasonal performance and an itemised scope.
Then ask who surveys, installs and commissions the system; what MCS paperwork, warranties and aftercare are included; and which assumptions remain provisional.
Home Energy Scotland strongly recommends comparing at least three installers
View sourceMCS design work should establish individual room heat losses
View sourceDemonstration evidence shows surveys must resolve varied real-home constraints
View sourcePut these questions into a FLO survey and quote
Tell FLO about the property and current heating. A survey turns the general guidance into a room-by-room design and written quote for the complete system.
Ask how the system was sized
Request the design outdoor temperature, room targets, fabric assumptions and heat loss for every heated space. The old boiler rating and floor area alone are not a design.
Check the selected unit’s output at the relevant outdoor and water temperatures, including its strategy for the coldest conditions.
Ask what changes inside the home
The proposal should identify radiators, pipework, cylinder, electrical work, controls, drainage and making good. Provisional allowances need clear triggers and prices.
Ask to see radiator outputs at the proposed flow and return temperatures rather than standard boiler ratings.
Ask how performance was estimated
A running-cost estimate should show annual heat demand, seasonal efficiency and tariff. Ask what hot-water and auxiliary electricity is included.
Avoid guaranteed savings based on one COP. A range with explicit assumptions is more honest and easier to compare.
Ask about people and aftercare
Know who will survey, design, install, commission and answer questions afterwards. Ask for MCS status, product warranties, workmanship cover and the complaints process.
A good handover explains the heating curve, schedules, hot water, backup heat, cleaning and the information to record if something feels wrong.
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Questions people also ask
Should I always take the cheapest quote?+
No. Compare scope, design assumptions, exclusions, warranties and aftercare as well as price.
What if the installer will not share calculations?+
Ask why. A useful proposal should make its core design assumptions visible.
Do I need an MCS installer for Scottish funding?+
Yes for supported heat-pump work under the current Home Energy Scotland Grant and Loan rules.
Evidence used for this answer
Figures are explained in context and links go to the independent source. Prices, tariffs, scheme rules and standards can change, so check the source again before making a financial or technical decision.
- Home Energy Scotland Grant and LoanCurrent eligibility, grant, optional loan, rural uplift and MCS requirements for Scottish homeowners.
- MCS heat-pump design standardTechnical requirements for heat loss, equipment selection, domestic hot water and system design.
- MCS domestic heat-pump guideConsumer guidance covering design, installation, controls, handover and maintenance.
- Energy Systems Catapult: home surveys and installation reportEvidence from 742 installations, including radiators, cylinders, survey constraints and typical installation duration.