We believe Aquatech’s Dynamic X8 (previously called “Hydrotherm”) is the best value heat pump hot water unit on the market.
In our article and video “How to Choose a Heat Pump Hot Water Unit“, we set out a framework of four key factors in analysing heat pump hot water units:
- Cost
- Reliability
- Refrigerant
- Maintenance
Below, we run the Dynamic X8 through our framework.
1. Aquatech Dynamic X8 Cost
A Dynamic X8 through Powrhouse costs around $1,700 – $2,300 fully installed (assuming customers are eligible for the Solar Victoria rebate).
A standard installation includes a plumber to disconnect and remove the existing unit, an electrician to wire the unit to the switchboard and Powrhouse to coordinate the installation and claim rebates and incentives on your behalf. Pricing will be lower if we don’t need an electrician (that is, we can plug the unit into an existing power point) and will be higher if the unit will be installed in a new location, if wiring costs extra or if there is no more room on the switchboard.
We’d describe this price as mid range. It’s at the lower end of the more affordable units (eg: iStore, Apricus, Haier, Rinnai) and considerably lower than the premium units (eg: Sanden, Reclaim). It’s more expensive than what we think are poorer quality units like Emerald, Ecogenica, Enviroheat.
2. Reliability and Warranty
When analysing reliability, we recommend people research reviews and online forums. It’s one thing to take our word, or a plumber’s word, but a multitude of reviews are very helpful. We also place greater value on reviews of units that have been operating for a long time. Reviews of units that have been operating for 5 years are more valuable than reviews of units that have been operating for 5 months. We like Product Review and the Facebook Group My Electric Efficient Home.
The Dynamic X8 currently rates as 4.7 on Product Review from hundreds of reviews. That’s an impressive result. You can’t please everyone and things will go wrong. The Reclaim Unit is widely considered the Rolls Royce of heat pump hot water units and receives 4.8.
Up until recently, the warranty has been the only thing letting the Aquatech units down. Whereas other mid-market units like iStore and Haier have 5 plus year warranties on both parts and labour, Aquatech only offered a 2 year labour warranty. We need heat pumps to last and I’ve always advocated that heat pump warranties should be longer.
On 20 August 2025, I was thrilled to see Aquatech increase its warranty to 5 years on both parts and labour. And it gets better – if you leave a review on ProductReview after installation, either positive or negative, Aquatech will increase the warranty 7 years, both parts and labour. With the exception of Reclaims and Sandens, which come with a price tag, I understand this is a market leading warranty.
I think this a wonderful show of faith by the company in its product.
3. Refrigerant
The Dynamic X8 uses Propane (R290) as a refrigerant. Propane has a Global Warming Potential (GWP) of 3 and is only bettered by Carbon Dioxide as a refrigerant with a Global Warming Potential of 1.
Previously there were a number of different refrigerants used in heat pump hot water units. This changed in 2024 when units using refrigerants with high GWPs were no longer eligible for rebates and effectively phased out of the market in Victoria. Most units nowadays use Propane.
I think it’s a great sign that Aquatech have been using Propane since 2011 as it means that they haven’t needed to change their manufacturing.
4. Maintenance
Aquatech’s heat pump hot water units are very easy to maintain. Owners are required to open the PTR valve and check the unit every six months, as well as a major service every five years. This is consistent with the better quality units on the market. Some poorer quality units even require a plumber to maintain the unit every six months, which is a pain and will drive up running costs over the long run.
At the risk of being too technical, one of the reasons why Aquatech’s units are so easy to maintain is they use an impressed current anode to protect the tank. Most units on the market use a sacrificial anode – a long rod of magnesium or other reactive metal that sacrifices itself instead of the tank. These are effective but they degrade, leading to a build up of residue which needs to be flushed, and they need to be checked and replaced. An impressed current anode on the other hand uses an electric current to protect the tank, resulting in less maintenance for owners.
Other Factors
A review of the Aquatech Dynamic X8 should also consider other factors:
- Noise – the unit operates at 43dB, at the lower end of the market
- Tank Recovery time – at around 270 mins (or 4.5 hours), this is consistent with the rest of the market
- Place of Manufacture – the units are manufactured in China, which is arguably another drawback, but most units on the market are made in China
Aquatech Dynamic X8 Review Summary
Powrhouse is independent. Powrhouse recommends the Dynamic X8 purely as a result of our thorough research of the heat pump hot water market. The Dynamic X8 ticks all the boxes: it’s reliable, affordable, low maintenance and many owners appear happy with their unit. The conclusion of this research is we think you would be a happy owner too.
If you are interested in a quote for a heat pump hot water unit, we’d love to hear from you.
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