A practical checklist for air-source and ground-source systems. This guide explains the decision points without promising that one answer fits every property.

Start with operating history

Changes in comfort, noise, electricity use or error codes direct the inspection.

For start with operating history, ask the designer to show the property evidence, assumptions and practical consequence rather than relying on a generic rule. Record the current fuel, annual consumption if available, rooms that struggle, desired temperatures, hot-water pattern and any planned renovation. A product figure measured under stated conditions is not a household bill forecast, so comparisons should identify the design temperature, intended water temperatures, controls and enabling work. Check who owns the heat-loss calculation, emitter schedule, electrical or ground scope, commissioning and handover. Avoid selecting equipment from floor area alone or treating a grant as proof that the system suits the home. Keep the final design, settings, warranties and service record so future adjustments and fault finding start from evidence.

Check both sides of the system

The heat source, water circuit, strainers, pressures, temperatures, safety devices, controls and hot-water operation all contribute.

For check both sides of the system, ask the designer to show the property evidence, assumptions and practical consequence rather than relying on a generic rule. Record the current fuel, annual consumption if available, rooms that struggle, desired temperatures, hot-water pattern and any planned renovation. A product figure measured under stated conditions is not a household bill forecast, so comparisons should identify the design temperature, intended water temperatures, controls and enabling work. Check who owns the heat-loss calculation, emitter schedule, electrical or ground scope, commissioning and handover. Avoid selecting equipment from floor area alone or treating a grant as proof that the system suits the home. Keep the final design, settings, warranties and service record so future adjustments and fault finding start from evidence.

Finish with useful evidence

A service should leave the homeowner with recorded findings and prioritised recommendations, not simply a ticked box.

For finish with useful evidence, ask the designer to show the property evidence, assumptions and practical consequence rather than relying on a generic rule. Record the current fuel, annual consumption if available, rooms that struggle, desired temperatures, hot-water pattern and any planned renovation. A product figure measured under stated conditions is not a household bill forecast, so comparisons should identify the design temperature, intended water temperatures, controls and enabling work. Check who owns the heat-loss calculation, emitter schedule, electrical or ground scope, commissioning and handover. Avoid selecting equipment from floor area alone or treating a grant as proof that the system suits the home. Keep the final design, settings, warranties and service record so future adjustments and fault finding start from evidence.

The practical next step

Use this information to ask better questions, then base the final decision on room-by-room heat loss, emitter output, site constraints and a written design. Renewable Heating Surrey can help turn the general principle into a property-specific assessment.