Gas boilers in Torrevieja and the Costa Blanca

Gas boiler or aerothermal: which to choose today on the Costa Blanca

Five years ago the answer was simple: gas boiler in almost every case. Today the decision is more nuanced and depends on the type of property, existing insulation level and investment horizon. The modern condensing gas boiler is still an excellent choice for homes with mains gas supply, particularly for apartments and flats where space for an aerothermal outdoor unit is limited or where the community doesn’t allow facade installations. Real condensing efficiency exceeds 100% on the lower calorific value of the gas, which translates into reasonable bills and controlled emissions.

Aerothermal is the most energy-efficient option but requires bigger upfront investment and space for the outdoor unit. For full renovations with new underfloor heating, aerothermal clearly wins. For replacement of an existing well-functioning boiler with installed radiators, switching to aerothermal makes sense but only when it’s naturally time to renew the boiler, not earlier.

What a boiler replacement covers

When the time comes to replace an old boiler, the full process typically takes a day. We start by shutting off gas and draining the heating circuit. We remove the old boiler, connection pipes and obsolete accessories. We clean the space and check the electrical board to confirm it can handle the new boiler (modern ones with modulating pump consume very little but need specific wiring).

We install the new boiler with updated accessories: properly sized expansion vessel, new safety valve, gas hose with accessible isolation cock, flue evacuation system with horizontal or vertical forced draft per your community’s rules, and automatic air vent at the highest point of the circuit. We configure parameters by installation type (radiators, underfloor or both) and tune the heating curve to local climate.

After the physical install, we run full commissioning with combustion analysis using an electronic analyser measuring CO, CO2, excess air and real efficiency. Only if all parameters are within standard do we sign the boletín and hand over the install certificate.

Annual servicing: why it really matters

Annual boiler servicing isn’t bureaucracy. It’s the technical inspection that catches potentially dangerous problems before they manifest. Proper service includes full combustion analysis (same parameters as the initial install, now measured to verify the boiler keeps its efficiency), heating circuit and DHW pressure check, safety valve verification, heat exchanger and burner cleaning, ignition electrode and thermocouple condition check, flue draft test and gas connection tightness verification.

The official RITE certificate handed over at the end is what your home insurer requires up to date to cover any boiler-related incident. Without a current certificate, a fault causing damage may not be covered. Annual review is mandatory for gas boilers between 20 and 70 kW, covering virtually all domestic ones.

Brands we recommend

Vaillant is our first recommendation for premium boilers. German engineering, robust electronics, excellent service network in Spain, official warranty up to 5 years. The EcoTec Plus range is the best-seller and covers most domestic needs.

Junkers (Bosch) is the second option with similar quality and slightly more competitive pricing. The Cerapur Excellence Compact range is robust and efficient.

Saunier Duval offers very good value, with ThemaPlus Condens as the reference for medium apartments and Renova Condens for larger homes.

For tighter budgets, Ferroli and Baxi are reasonable alternatives, noticeably below the premium tier in quality but adequate for standard domestic use.