Assess First. Recommend Second.
Compare pure and sustain configurations, then choose the right heating arrangement.
The existing ecoFIT overview now links to the pure homeowner and sustain specification families. Both names include multiple arrangements with separate output tables and guarantee considerations.
A compact combi family with three hot-water output choices.
Model labels: 25 kW | 30 kW | 35 kW
Warranty: Up to 10 years, subject to the eligible package
Range: Homeowner / domestic range
Key takeaway: A compact casing does not remove service-clearance requirements. Check water flow and simultaneous demand before selecting the combi output.
Explore ecoFIT pure Combi
Five cupboard-oriented system outputs for separate stored hot water.
Model labels: 12 kW | 15 kW | 18 kW | 25 kW | 30 kW
Warranty: Up to 10 years, subject to the eligible package
Range: Homeowner / domestic range
Key takeaway: Choose the boiler and cylinder together: cylinder capacity, recovery and controls determine the stored-water result.
Explore ecoFIT pure System
Six regular-boiler output labels with a separate cylinder and external system components.
Model labels: 12 kW | 15 kW | 18 kW | 25 kW | 30 kW | 35 kW
Warranty: Up to 10 years, subject to the eligible package
Range: Homeowner / domestic range
Key takeaway: Do not confuse the pure 425 / 25 kW with the ecoTEC plus 424 / 24 kW. Each belongs to a different family with its own ratings.
Explore ecoFIT pure Open Vent
A compact combi configuration from Vaillant’s specification range.
Model labels: 25 kW | 30 kW | 35 kW
Warranty: Project guarantee duration requires confirmation
Range: Specification / project range
Key takeaway: The March 2025 specification brochure lists the same CH maximum for all three combi labels. DHW labels and verified flow are shown without inventing a missing DHW heat-output figure.
Explore ecoFIT sustain Combi
Three system labels for specification projects retaining a hot-water cylinder.
Model labels: 15 kW | 18 kW | 30 kW
Warranty: Project guarantee duration requires confirmation
Range: Specification / project range
Key takeaway: Only the 15, 18 and 30 kW system labels are confirmed in the current specification table; the directory’s combined range list must not be applied to every arrangement.
Explore ecoFIT sustain System
Regular-boiler variants for cylinder-and-external-component specification projects.
Model labels: 15 kW | 18 kW | 30 kW
Warranty: Project guarantee duration requires confirmation
Range: Specification / project range
Key takeaway: The current manufacturer table confirms 15, 18 and 30 kW labels for this arrangement. Other outputs in the range-wide directory belong to different configurations.
Explore ecoFIT sustain Open VentSuitability depends on calculated heating and hot-water requirements, the existing system and installation constraints. The Boiler Finder offers initial research guidance; the final recommendation requires professional assessment.
The installed price for your selected boiler is confirmed after assessment. The quotation covers the appliance, controls, flue, system preparation and any required pipework. A conversion or relocation can have a different scope from a straightforward replacement.
New boiler installations from £1,790 inc. VAT apply to a qualifying standard, straightforward replacement: one bathroom, fewer than 10 radiators and a standard horizontal flue, subject to survey. Specification and warranty selection affect the final cost. This is a general starting offer and is not a price for every model in this catalogue.
Read the starting-package conditions0% options over 3, 6, 9 or 12 months through Humm Group Limited, subject to application, affordability, eligibility, approval and provider terms. Any applicable deposit, fees and repayment conditions are confirmed during your enquiry/application. Acceptance is not guaranteed.
Finance terms and chargesTwo free annual services and a Hive Mini are available on qualifying installations only. Every model is considered under the qualification rules; inclusion in this catalogue does not confirm eligibility. Ask us to confirm the offer in your quotation.
Ask about Care+ eligibilityPlan the maintenance your appliance requires and keep its service records. If you are considering replacement because of a fault, diagnosis can help establish whether repair is a suitable option first.
Boiler servicing · Repair advicePrice confirmed following assessment for this configuration. The general New boiler installations from £1,790 inc. VAT offer does not apply to every model or property.
From or indicative prices remain provisional. SwiftHeat issues a written fixed quotation for the agreed scope after the appropriate property and installation assessment, technical checks and warranty-package verification. Remote information gathering may be suitable initially; a home survey is required where the necessary checks cannot be completed remotely.
We assess heat loss, heating and hot-water requirements, water supply, controls and installation access before recommending an appliance. Bedroom count or a catalogue model number alone cannot establish the right boiler.
Gas Safe registration 978273 · Serving Cardiff, South Wales and across the UK.
Understand suitable boiler types · Start the Boiler Finder · Our installation assessment · Areas we cover
