Thermann hot water: what the brand covers and what to ask before you buy
A quote that says Thermann tells you the badge and nothing about the system. Storage, continuous flow, solar and heat pump are four different installations with four different sets of site needs.
Thermann is a brand name, not a type of hot water system. The range described on the brand's own site covers electric storage, gas continuous flow, solar boosted and heat pump systems. Picking the badge therefore settles very little.
What decides your week is the type: stored volume or capped flow rate, electric or gas or heat pump. Your house decides that, not the label. This page is an independent guide to what to check before you buy; we have no relationship with the brand and sell nothing.
What kinds of system does Thermann sell?
Thermann describes itself as an Australian-owned brand and, as far as we can tell from its own site and from retailers, sold through one plumbing supply network rather than through every shop. Check that with the seller, because where a brand is sold decides who you phone when something fails.
| Type | What it is | What your house needs for it |
|---|---|---|
| Electric storage | An insulated tank heated by an element | Tank footprint, and a tariff decision. Off-peak heating means a bigger tank. |
| Gas continuous flow | Heats water as it passes through, no tank | A gas supply sized for the unit, wall space, and a flow rate that suits your outlets. |
| Solar boosted | Roof collectors, a tank and a booster | Suitable roof orientation and structure, plus space for the tank. |
| Heat pump | A tank with a refrigeration unit | Clear airflow, condensate drainage, and a spot where compressor noise is acceptable. |
These are different installations, not trim levels. Our comparison of the four system types is the step that belongs before this page.
Is Thermann a good brand?
We cannot rank brands, and we will not pretend to. We have not tested the units and we publish no failure statistics, because we do not have any. What we can tell you is how to judge any brand: parts, service coverage and a warranty you have actually read.
Spare parts and a service network that still covers your postcode in ten years matter more than the name. Ask the seller who services the unit locally, and ask in writing. A cheap system with no local service is a poor deal whatever it is called.
How do you identify the Thermann you already have?
Find the data plate, a label on the outer jacket of a tank or on the casing of a wall-mounted unit. It carries the model, the serial number and, on gas appliances, the gas type. Photograph it.
That one photo is worth more than any phone description. It tells a technician what is coming, and it tells you whether a replacement quote compares like with like. Our guide to hot water brands explains why the badge and the model are different questions.
What should you get written on the quote?
- The full model designation, and the gas type where it applies.
- Tank volume and recovery rate for storage, heat pump and solar. These two numbers decide whether you run out.
- Litres per minute at a realistic winter temperature rise for continuous flow. Winter mains water is colder than the headline figure assumes.
- Siting and clearances in writing. Gas appliances need minimum distances from windows, doors and vents.
- Tempering valve, relief valve discharge and isolation valve. These are the items most often missing from the cheapest quote.
- The installer's licence number and the compliance certificate for the work.
How far can you take this yourself?
Photographing the data plate, working out which type you are being quoted, measuring the space and getting the items above onto the quote are all yours. None of them needs a licence.
This far, and no further. Installing, replacing or repairing a hot water system is licensed plumbing work in every Australian state and territory. Anything on the gas side also needs gasfitting authorisation, and the electrical connection is licensed electrical work.
Do not relight a pilot, open a burner compartment or open the electrical enclosure of any unit. Licensing and compliance paperwork are set by each state and territory. So check with the plumbing regulator where you live and ask for the licence number before work starts.
Frequently asked questions
What types of hot water system does Thermann sell?
The brand's own site describes electric storage, gas continuous flow, solar boosted and heat pump systems. These are different installations, so the brand does not choose the type. Work out which type your house can take first, then compare models.
How do I find the model of my Thermann hot water system?
Look for the data plate on the outer jacket of the tank or on the casing of a wall-mounted unit. It gives the model, the serial number and, on gas appliances, the gas type. Photograph it before you phone anyone.
Can I replace a Thermann hot water system myself?
No. Installing or replacing a hot water system is licensed plumbing work in every Australian state and territory, and gas and electrical connections need their own licensed trades. You can photograph the data plate and measure the space.
What should a Thermann quote include?
The full model designation, tank volume and recovery rate or flow rate, siting clearances, the tempering valve, relief valve discharge and isolation valve, and the installer's licence number. Ask for the compliance certificate when the work is done.
Sources
What this page explains is based on these official sources. If you check one and it does not match what you read here, send it to us and the article gets corrected.
- Australian Government, energy.gov.au. Hot water systems — types, installation and energy performance
- Australian Building Codes Board. National Construction Code — Volume Three (Plumbing Code of Australia)