A hydronic system's pipes and emitters can outlast more than one heat source, so the smartest decision isn't only “which unit today” but “what will this home run on next time”. We talk this through with every client weighing the Magis against the Brava Slim.
If you choose the Sime now
For a gas-connected home with large existing radiators, the Sime is often the pragmatic, lower-capital choice. But we'll design it so a heat pump can follow later without a rebuild: we check that the radiators can still heat their rooms at lower water temperatures (upsizing the weakest one or two), fit the outdoor climatic sensor so the boiler already runs cooler on mild days, and note where a future outdoor unit could sit with the clearance it needs. That way your next replacement is a swap, not a redesign, and the money you spend on emitters today keeps working for you.
Gas policy is worth weighing as well. Victoria no longer allows new gas connections for most new homes and the ACT has stopped new gas network connections, so for new builds there the Magis is usually the only sensible path. In Sydney and Brisbane the choice remains open and comes down to tariffs, solar, the age of your existing system and whether you want cooling.
If you choose the Magis now, the main decisions are electrical and spatial. The largest band is three-phase only and needs generous rear clearance, so we confirm both at the site visit. If you'll want summer cooling, it's cheaper to insulate pipework and plan fan-coil condensate drains during the install than to add them later — our hydronic cooling guide explains why.
Either way, the emitters do the heavy lifting on comfort. Our hydronic radiator heating page covers radiator choice and sizing, and if you're upgrading an older system the hydronic retrofit guide sets out the steps from survey to commissioning.
