Rinnai vs Rheem: Australia's Two Most Popular Hot Water Brands
When Australian homeowners need a new hot water system, Rinnai and Rheem come up more often than any other brands. Both have been in the Australian market for decades, both offer a full range of continuous flow and storage systems, and both are trusted by plumbers nationwide. This guide compares them honestly.
Brand Background
Rinnai
Rinnai is a Japanese company founded in 1920. It is one of the world's largest manufacturers of gas appliances and has been in Australia since the 1970s. Rinnai is known for compact, efficient continuous flow (instantaneous) hot water systems and is widely regarded as one of the most reliable brands in this category.
Rheem
Rheem is an American brand, though Rheem Australia operates as a separate entity producing locally relevant products. Rheem is known for storage hot water systems (both gas and electric) and heat pump hot water systems. The Rheem name is closely associated with the traditional storage tank in many Australian minds.
Head-to-Head Comparison
| Category | Rinnai | Rheem |
|---|---|---|
| Continuous flow (instantaneous) | Market leader, extensive range | Good range, slightly less dominant |
| Gas storage | Available | Strong range |
| Electric storage | Limited | Strong range |
| Heat pump | Yes (Rinnai Hotflo) | Yes (Rheem Ambiheat) — market leader |
| Solar hot water | Yes | Yes |
| Price range (continuous flow) | $900 – $2,200 installed | $950 – $2,100 installed |
| Warranty (unit) | 12 years heat exchanger | 10 years heat exchanger |
| Plumber familiarity | Very high | Very high |
Continuous Flow: Which Is Better?
For continuous flow gas hot water, Rinnai is generally considered the benchmark in Australia. Models like the Rinnai B26 and HDi26 are extremely popular, well-serviced and have an excellent track record. Rheem's continuous flow systems are also good, but Rinnai has the edge in this category.
Heat Pump: Which Is Better?
For heat pump hot water (which runs on electricity and is eligible for government rebates), Rheem's Ambiheat range is widely regarded as the market leader. It has strong installation numbers, good efficiency ratings and an established service network. Rinnai's heat pump offering is newer and less proven in this category, though improving rapidly.
Reliability and Servicing
Both brands have extensive service networks in Sydney. Spare parts are readily available for both. Neither brand has a significant reliability advantage in independent consumer surveys — both are well above average.
Which Should You Choose?
- Continuous flow gas: Rinnai (slightly preferred by most plumbers)
- Heat pump electric: Rheem Ambiheat (market leader in this category)
- Gas storage: Either brand — compare on price and capacity
- Electric storage: Rheem has the broader range
Note on Oceania Appliances
Oceania Appliances focuses on kitchen and laundry appliances rather than hot water systems. For hot water installation, we recommend consulting a licensed plumber who can advise on the right system for your household size, gas connection and rebate eligibility. For all other home appliances, visit us at 2/14 Centre Place, Wetherill Park, call or WhatsApp 0422 489 492, or email support@oceaniaappliances.com.au. Open 7 days, 10am–8pm.