Hot water in Narre Warren.

The 2005–2012 Rinnai Infinity bulge.

Most of Narre Warren and Narre Warren South was built or re-developed between 2005 and 2012. Default install at the time was a Rinnai Infinity 24 or 26 gas instantaneous mounted externally on the side or rear wall, ducted off internal copper. Those units are now 13–20 years old — a Rinnai Infinity easily lasts 20+ years but the electronic ignition board is the wear-out point. Symptoms: unit clicks but doesn’t fire, intermittent hot, error codes 11 / 12 / 14 on the controller. Board replacement is $400–$650; full unit replacement starts to make sense at the 20-year mark.

3-4 bedroom family homes — size matters.

Narre Warren is family country. 3–4 bedroom homes, 2 bathrooms, dishwasher, washing machine, kids in showers morning and evening. A 20L/min Infinity 24 was undersized from day one for many of these households — the lukewarm-shower-when-dishwasher-runs problem. We upsize to 26L/min Infinity or Bosch Highflow 26e on most replacements. For families ready to electrify, a 280–315L heat-pump comfortably handles peak demand.

Heat-pump conversion is the smart upgrade.

For an owner-occupier family in Narre Warren paying ~$1,000/year for gas hot water, a heat-pump conversion (Reclaim 280L, Sanden 315L, Stiebel Eltron 300L) lands at $3K–$4.5K net after the $1,000 Solar Vic rebate plus STCs. Running cost drops to ~$300/year — $700/year saving, 4–5 year payback on the conversion premium. We mount compressors on the side wall well clear of bedroom windows; most installs are sound-rated 45–48 dB and inaudible inside.

Typical Narre Warren jobs.

• Rinnai Infinity 24 board replacement (15-year-old unit) — $400–$650
• Infinity 24 to Infinity 26 upgrade (sized for family demand) — $2.3K–$2.8K
• Gas instantaneous to heat-pump conversion (Reclaim 280L) — $3.5K–$4.5K net after rebates
• Heat-pump compressor placement next to existing AC condenser
• Same-day no-hot-water repair — $200–$500