Rinnai Infinity B12

The Rinnai Infinity B12 is a continuous flow (instantaneous) gas hot water system that delivers 12 litres of hot water per minute. It is designed for 1-2 person households with a single bathroom, units, granny flats, and small homes or apartments where demand is consistent but not high. Rinnai is one of Australia’s most trusted hot water brands with a strong service network, and the B12 is the entry point into the Rinnai Infinity Builder series, which balances reliable Japanese engineering with a competitive price point.

The Rinnai B Series (Builder series) and the Rinnai Infinity series are largely identical internally. Both use the same burner, heat exchanger, and core components, and both carry a 6.1-star energy rating. The key differences are cosmetic and warranty-related. The Infinity models have a small LED/LCD display showing the operating temperature. The B series does not include this display. The Infinity heat exchanger warranty is 12 years, while the B series heat exchanger warranty is 10 years. The B Series is typically less expensive as a result, making it the practical choice for most homes where a front-panel display is not a priority.

Yes. The Rinnai Infinity B series uses electronic ignition powered by either a 240V power point or D-cell batteries, depending on the configuration. Most standard Perth installations use a power point connection. If no power point exists at the proposed installation location, Ember can arrange to have one installed as part of the job. The benefit of electronic ignition over a standing pilot light is that no gas is consumed when the unit is idle, the burner is completely off until a hot tap is opened.

The Rinnai Infinity B12 carries a 6.1-star energy rating, which is among the highest available for residential gas continuous flow systems. This rating reflects the efficiency of the electronic ignition (no standing pilot gas cost) and the effectiveness of Rinnai’s Puretemp temperature control technology, which modulates the burner output to maintain a consistent temperature and avoid energy-wasting overheating. Over a full year, a 6.1-star system will use meaningfully less gas than a 4.6-star system delivering the same volume of hot water.

The Rinnai Infinity B12 includes a 12-year warranty on the heat exchanger and a separate warranty on parts and labour for domestic installations. As noted on Ember’s website, the full warranty terms are confirmed at the time of installation. Rinnai has one of the largest service networks in Australia, which is a practical consideration for warranty claims — a local Rinnai-authorised technician is available across all Perth metro areas. Ember’s installation also includes a Certificate of Compliance for the gas work, which is required for warranty claims to be valid.

Both models deliver 12L/min and carry a 12-year heat exchanger warranty. The Rinnai B12 is priced at $1,399 installed and the Rheem 12 at $1,299; a $100 difference. The Rinnai B12 has a slightly higher energy rating (6.1 stars vs the Rheem 12’s 6 stars) and uses Rinnai’s Puretemp technology for consistent temperature control. Rheem products installed by Ember come with Ember’s additional 2-year extended warranty, which adds value to the Rheem 12. Both are strong performers for single-bathroom homes, and Ember’s team is happy to discuss which is the better fit for your specific property.