Stiebel Eltron vs Emerald: Which Heat Pump Is Better? (2026)

Quick Verdict

Emerald is the more efficient choice with a higher COP rating, meaning lower running costs over time.

Side-by-Side Comparison

FeatureStiebel EltronEmerald
Price range (installed)$3,500 - $5,000$2,750 - $3,750Lower
COP (efficiency)3.85.2Higher
Tank warranty5 years7 yearsLonger
Compressor warranty5 years5 years
Noise level44dBQuieter49dB
Annual running cost~$312/yr~$228/yrLower
Refrigerant typeR134aR134a
Country of manufactureGermanyAustralia
Australian madeNoNo
Best forThose who value German engineering and build quality at a mid-to-premium price pointHouseholds wanting a high published efficiency and a long tank warranty without paying split-system prices

Price Comparison

Stiebel Eltron starts from $3,500 installed (before rebates), while Emerald starts from $2,750. That is a difference of roughly $750 at the entry level. Emerald is the more budget-friendly option upfront, though Stiebel Eltron 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. Stiebel Eltron achieves a COP of 3.8, while Emerald reaches 5.2. The Emerald is 37% more efficient, which translates to roughly $84 less per year in running costs. Over a 10-year lifespan, that efficiency advantage adds up to approximately $840 in savings.

Warranty Comparison

Stiebel Eltron offers a 5-year tank warranty and 5-year compressor warranty. Emerald offers a 7-year tank warranty and 5-year compressor warranty. The Emerald has the stronger warranty coverage with 7 years on the tank, giving you 2 extra years of protection compared to the Stiebel Eltron. 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. Stiebel Eltron publishes 44dB for its quietest model, and Emerald publishes 49dB. The Stiebel Eltron is quieter at 44dB. At this level, it is similar to a quiet office and should be unnoticeable from inside most homes.

Climate Suitability

The type of refrigerant a heat pump uses significantly affects its performance in cold weather. Stiebel Eltron uses R134a refrigerant, while Emerald 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

Stiebel Eltron

Pros

  • German engineering quality
  • Good efficiency
  • Solid warranty backing
  • Established global brand (100+ years)
  • Strong Australian support network

Cons

  • Higher cost than local brands
  • Heavier unit
  • Not Australian-made (misses higher VIC rebate tier)

Emerald

Pros

  • Among the cheapest R290 units with a published COP above 4.8
  • Pro series carries a 7-year tank warranty, 8 if you register it
  • Two magnesium anodes on the Pro tank
  • Widely stocked, so quotes are easy to compare
  • Runs on the heat pump alone down to -7C

Cons

  • Manufacturing location is not published
  • Not on the Solar Victoria locally made list, so it earns the lower Victorian rebate tier
  • The Select series drops to a 5-year tank and 2-year labour warranty
  • Emerald quotes 39 to 40 dB from 3 metres on its web pages while the data sheets show 49 to 50 dB at 1 metre, so compare it with other brands at 1 metre

Which Should You Choose?

Choose Stiebel Eltron if...

  • Quiet operation matters to you (44dB vs 49dB)

Choose Emerald if...

  • You want a lower upfront cost (from $2,750 vs $3,500)
  • You want the best efficiency and lowest running costs (COP 5.2 vs 3.8)
  • You want a longer tank warranty (7 years vs 5 years)
  • You want lower annual running costs (~$228/yr vs ~$312/yr)

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.

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