Sanden Heat Pump Hot Water Review (Eco Plus)

If you want a quiet, very efficient hot water system that copes well with cold mornings, the Sanden Eco Plus heat pump is one of the best options in Australia. It’s premium-priced and needs space for a separate outdoor unit and tank, but delivers low running costs and dependable hot water for most homes.

What the Sanden Eco Plus is (and how it works)

The Sanden Eco Plus is a split heat pump hot water system. The outdoor heat pump unit sits outside like a small air conditioner and extracts heat from the air, using it to warm water in a separate stainless-steel tank via a closed loop. It uses CO₂ (R744) refrigerant, which is well regarded for efficiency and strong cold-weather performance. Unlike resistive electric storage, a heat pump moves heat rather than making it, so it typically uses a fraction of the electricity for the same hot water.

Because it heats water to around 60°C, you get hygienic storage without needing an electric “boost” element for everyday use. A tempering valve is fitted (as required in Australia) to deliver safe hot water to taps while keeping the tank hot enough for bacterial control.

Verdict at a glance

Pros

• Excellent efficiency and low running costs compared with conventional electric storage and gas.
• CO₂ refrigerant gives strong performance on frosty mornings and rapid heat-up when the tank is low.
• One of the quieter heat pumps, easier to place near living areas with thoughtful siting.
• Stainless steel tank option and generally robust build quality.
• Simple controls with timer capability, handy for solar PV and off-peak tariffs.

Cons

• Premium upfront price; you’re paying top dollar versus budget heat pumps or basic electric storage.
• Two-piece installation needs outdoor space and careful placement to meet noise and clearance requirements.
• Lead times and installer availability can vary by region.
• Not ideal for apartments or homes without suitable outdoor airflow.

Real-world performance and noise

Owners choose the Sanden largely for its reliability and efficiency in varied Aussie climates. The CO₂ refrigerant allows efficient operation in cold conditions, so even in inland frosts or alpine towns you can expect stable hot water without heavy energy use. In warm coastal areas it’s even more efficient.

Noise is a common concern with heat pumps. The Sanden Eco Plus is widely regarded as quiet by heat pump standards. You’ll hear a gentle fan and compressor hum when it runs, typically during heating cycles set by your timer or after large draws. Good placement still matters: keep it off bedroom walls if you can, allow clearance around the fan, and avoid acoustic “echo” corners. Your installer should follow the manufacturer’s siting guide and any council noise rules.

Expect normal heat-pump behaviours: a light plume of vapour on cold mornings, occasional defrost cycles (you may see some condensate water), and a steady whirr when the unit is bringing the tank back to temperature after showers or a bath.

Sizing and installation: what to plan for

The Sanden system comes as a separate outdoor heat pump plus a matched storage tank in multiple sizes. The right tank depends on household size and habits:

• Singles/couples with simple shower use: smaller tanks are usually fine.
• Families (3–5 people), frequent showers and laundry: medium tanks suit most.
• Large families, long showers, or regular baths: consider the largest tank for buffer capacity.

As a rule of thumb, a typical four-person family often chooses a medium-to-large tank. If you love back-to-back showers, add a safety margin. See our heat pump sizing guide for more detail.

Installation needs a licensed plumber and electrician. Key points:

• Siting: Place the outdoor unit where it gets free airflow. Avoid tight enclosures. Keep pipe runs short between the unit and the tank for best efficiency.
• Noise: Put distance and structure between the unit and bedrooms or neighbour windows if possible.
• Drainage: Ensure a proper condensate drain for defrost water.
• Electrical: The Sanden typically runs on a standard single-phase supply. Your electrician will connect it to a dedicated circuit and set up timers if needed.
• Plumbing: A tempering valve, pressure/temperature relief valve and correct insulation on all hot and cold lines are essential. Keep the tank as close as practical to the main bathrooms/kitchen to minimise wait times and heat loss.

Running costs, tariffs and solar PV

Compared with a conventional electric storage heater, a well-set-up heat pump like the Sanden often uses a quarter to a third of the electricity for the same hot water. That translates to meaningful bill savings, especially in all-electric homes.

You can run it on an off-peak/controlled-load tariff or time it to heat in the middle of the day on solar PV. Each has pros and cons:

• Off-peak tariff: Lower kWh price overnight, but limited hours. Make sure the tank is sized to carry you through morning demand. See our guide to off-peak hot water.
• Solar PV: Use the timer to heat from late morning to mid-afternoon, soaking up your excess solar. This can drive running costs very low in sunny months.

Many households do a hybrid approach: prioritise a solar window on most days, with a smaller off-peak top-up overnight in winter. A competent installer can set this up on the controller or via your switchboard timer.

Price, value and how it compares

The Sanden Eco Plus sits at the premium end of the market. You’re paying for efficiency, quiet operation and proven cold-weather performance. If you’re replacing an old electric storage unit or getting off gas, the long-term savings and comfort can justify the upfront outlay, particularly for families with steady daily hot-water use and solar PV.

If your budget is tight, there are cheaper heat pumps, but they may be louder, slower to recover after heavy use, or less efficient in winter. Conversely, if you want a “buy once, cry once” option with strong performance in a range of climates, the Sanden is a solid pick.

Rebates and certificates to check (NSW, VIC and federal)

Three main incentives can apply to heat pump hot water in Australia. Availability and eligibility change, so check the official scheme pages before you buy:

• Federal STCs: Small-scale Technology Certificates under the Small-scale Renewable Energy Scheme reduce upfront cost at the point of sale. The value depends on location and deeming period.
• NSW Energy Savings Scheme (ESS): Provides incentives for approved hot water upgrades. Installer participation and product eligibility are key—ask your retailer to confirm.
• VIC Solar Homes hot water rebate: The Victorian program offers support for eligible households upgrading to heat pump hot water. Check current criteria and application steps.

Because rebate rules change, get two or three quotes from approved installers who can confirm which incentives apply to your address and how they’re applied to the final price.

Maintenance and reliability

Heat pumps are low-maintenance compared with combustion systems. Plan for:

• Rinsing or brushing the outdoor coil and keeping leaves/debris clear each season.
• Operating the pressure/temperature relief valve briefly every six months to prevent sticking (follow the manufacturer’s instructions).
• Annual check by a licensed plumber to confirm valves, insulation and controller settings are in good order.

The Sanden’s stainless steel tank design typically avoids sacrificial anode replacements common in glass-lined tanks. Always read the current warranty booklet and servicing requirements to keep coverage intact.

Who the Sanden Eco Plus suits (and who it doesn’t)

• Great fit if: You have solar PV and want to shift hot water to sunny hours; you live in a cooler climate; you’re replacing an old resistive electric system; you value quiet operation.
• Think twice if: You’re in an apartment or have no suitable outdoor spot; your budget can’t stretch to a premium heat pump; you need to tuck the unit into a tight or echo-prone alcove near bedrooms.

If you’re unsure, ask an installer to assess siting options, expected noise at your boundary, and the right tank size for your usage pattern.

Bottom line: if you can accommodate the outdoor unit and the upfront cost, the Sanden Eco Plus is a top-tier, efficient and quiet hot water upgrade that pairs beautifully with solar and handles cold weather better than most.