Rheem vs iStore: Which Heat Pump Is Better? (2026)
Quick Verdict
Rheem is the more efficient choice with a higher COP rating, meaning lower running costs over time, while iStore is more budget-friendly with a lower upfront cost starting from $2,800.
Side-by-Side Comparison
| Feature | Rheem | iStore |
|---|---|---|
| Price range (installed) | $3,200 - $4,800 | $2,800 - $4,400Lower |
| COP (efficiency) | 3.5Higher | 3.2 |
| Tank warranty | 10 yearsLonger | 5 years |
| Compressor warranty | 5 years | 5 years |
| Noise level | 47dBQuieter | 49dB |
| Annual running cost | ~$338/yrLower | ~$370/yr |
| Refrigerant type | R134a | R134a |
| Country of manufacture | Australia | Australia |
| Australian made | Yes | No |
| Best for | Homeowners who want a reliable, well-supported mid-range option from a trusted Australian brand | Budget-conscious households wanting maximum rebate impact and simple installation |
Price Comparison
Rheem starts from $3,200 installed (before rebates), while iStore starts from $2,800. That is a difference of roughly $400 at the entry level. iStore is the more budget-friendly option upfront, though Rheem may deliver savings through lower running costs over time. Both prices are for fully installed systems before government rebates and STCs, which can reduce the out-of-pocket cost by $1,000 to $3,000 depending on your state.
Efficiency Comparison
COP (Coefficient of Performance) is the key efficiency metric for heat pumps. A higher COP means more heat output per unit of electricity consumed. Rheem achieves a COP of 3.5, while iStore reaches 3.2. The Rheem is 9% more efficient, which translates to roughly $32 less per year in running costs. Over a 10-year lifespan, that efficiency advantage adds up to approximately $320 in savings.
Warranty Comparison
Rheem offers a 10-year tank warranty and 5-year compressor warranty. iStore offers a 5-year tank warranty and 5-year compressor warranty. The Rheem has the stronger warranty coverage with 10 years on the tank, giving you 5 extra years of protection compared to the iStore. A longer tank warranty can provide significant peace of mind, as the tank is the most expensive component to replace.
Noise Comparison
Noise is an important consideration, especially for suburban installations where the unit may be close to bedrooms or neighbouring properties. Rheem publishes 47dB for its quietest model, and iStore publishes 49dB. The Rheem is quieter at 47dB. At this level, you may want to consider placement carefully to avoid disturbing bedrooms or neighbours.
Climate Suitability
The type of refrigerant a heat pump uses significantly affects its performance in cold weather. Rheem uses R134a refrigerant, while iStore uses R134a. Both units use the same refrigerant type, so cold-weather performance should be comparable. R134a performs well in moderate climates but may lose some efficiency in very cold conditions.
Pros and Cons
Rheem
Pros
- Well-known trusted brand
- Wide installer network
- Integrated design (simpler install)
- Competitive pricing
- Australian made and owned
Cons
- Shorter warranty than premium brands
- Lower COP than Sanden/Reclaim
- Noisier than split systems
- R513a refrigerant, not the CO2 used by the premium split systems
iStore
Pros
- Most affordable option
- Australian owned and supported
- Simple installation
- Good rebate value (low cost means rebates cover more)
- Widely available
Cons
- Lower COP than premium brands
- Shorter warranty
- Noisier than split systems
- Higher running costs long-term
- Units manufactured overseas
Which Should You Choose?
Choose Rheem if...
- You want the best efficiency and lowest running costs (COP 3.5 vs 3.2)
- You want a longer tank warranty (10 years vs 5 years)
- Quiet operation matters to you (47dB vs 49dB)
- You want lower annual running costs (~$338/yr vs ~$370/yr)
- You're in Victoria (models on Solar Victoria's locally made list = higher rebate tier of $1,400 vs $1,000)
Choose iStore if...
- You want a lower upfront cost (from $2,800 vs $3,200)
Buying in Victoria? Stack up to $2,700 in rebates
Whichever brand you pick, Victorian households can stack the Solar Victoria Hot Water Rebate ($1,000-$1,400), the Victorian Energy Upgrades discount ($500-$2,000), and federal STCs ($500-$1,200) ahead of the 1 March 2027 gas ban deadline. Rheem has models on Solar Victoria's locally made list, which qualify for the higher $1,400 tier.
Heat pump guides
- Every Australian heat pump rebate, with the dated changes
- The best heat pump hot water brands in Australia
- Heat pump hot water cost in Australia
- Victoria heat pump rebates
- New South Wales heat pump rebates
- Queensland heat pump rebates
- South Australia heat pump rebates
- Australian Capital Territory heat pump rebates
- Western Australia heat pump rebates
- Tasmania heat pump rebates
- Northern Territory heat pump rebates
What are you replacing?
Tap one to continue