BoilerBuying Guide2025-10-08
Combi vs Conventional Boiler: Which Is Best?
Combi boilers save space and give on-demand hot water; conventional systems suit high simultaneous demand.
Choosing between a combi and a conventional (system) boiler depends on your home's size, hot-water demand and space.
Combi boilers
A combi heats your home and provides hot water on demand from one compact unit — no tank, saving space and standby losses. Ideal for small-to-medium homes and condos.
Conventional / system boilers
Systems with a hot-water cylinder suit larger homes with multiple bathrooms used simultaneously, where a combi's flow rate could be a limitation.
Key takeaways
- Combi suits space-limited homes and condos
- Conventional suits multiple simultaneous showers
- Combis remove tank standby losses
- Right choice depends on peak hot-water demand
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