BoilerComparison2026-02-20
System vs Combi vs Conventional Boilers
Combis need no tank; system and conventional setups use cylinders for high simultaneous demand.
Three boiler types suit different homes. Here's a quick guide to choosing.
Combi boilers
Heat and hot water on demand from one unit, no tank — ideal for small-to-medium homes and condos.
System and conventional
Use a hot-water cylinder (and a cold tank for conventional) to serve larger homes with multiple simultaneous showers.
Key takeaways
- Combi: compact, no tank
- System: cylinder for higher demand
- Conventional: cylinder + cold tank, older style
- Choose by peak hot-water demand
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