JR GAS & WATER INSTALLER ASSESSMENT
Our Electric Hot Water Installer Verdict
This is the part of the product page we consider most important. It is our assessment of the product from the installer's side: construction, installation, commissioning, service access and manufacturer support, rather than a repeat of the specification sheet.
Local Hot Water Installation Areas
View all hot water service areas🏷️ Brand: Thermann
🔢 Model Number: Smart 125L
📦 Volume: 125L
📏 Width: 530 mm
📐 Height: 1090 mm
🌍 Manufactured In: Australia
🛠️ Cylinder / Heat Exchange Material: Steel Enamel
🛡️ Cylinder / Heat Exchange Warranty: 10 Years
🔇 Noise Level: NA dBa
⚖️ Dry Weight: kg
⚡ Energy Source:
📡 WiFi Controller: Yes
⏲️ Built-In Timer: Yes
💡 LED/LCD Status Indicator: No1
📊 Coefficient of Performance (COP):
Thermann Smart Electric 125L Installation Brisbane & Gold Coast
The Thermann Smart Electric 125L combines conventional electric storage with built-in Wi-Fi, app scheduling and energy-use monitoring for households wanting greater control over when their water heater operates.
Thermann publishes 125 litres of hot-water delivery from approximately 130 litres of actual storage. The tank measures 1090mm high × 530mm diameter, weighs approximately 51kg empty and is available with 1.8kW, 2.4kW or 3.0kW single-element configurations.
Thermann's current sizing guide places the 125L model at approximately 3–4 people with continuous electrical supply or 3 people on off-peak supply. Actual suitability still depends on shower length, fixture flow, household habits and tariff arrangement.
Quick answer: the Thermann Smart 125 is a 125L-delivery smart electric storage system with 130L actual tank capacity, built-in Wi-Fi, Manual, Eco, Holiday and Schedule modes, 1.8–3.0kW element options and manufacturer recovery rates up to 51.6L/hr at a 50°C rise.
Thermann Smart 125L at a Glance
Hot-Water Delivery
The model is sold as 125L based on its published hot-water delivery, with approximately 130L actual storage capacity.
Thermann Control App
View energy use and power cost, select operating modes and create heating schedules from the compatible app.
Element Options
Current manufacturer configurations include 1.8kW, 2.4kW and 3.0kW single-element versions.
Compact 125L Format
Approximately 1090mm high and 530mm diameter before allowing for plumbing and service access.
Who Is the Thermann Smart 125L Best For?
Smaller Households
A compact smart-storage option where 125L of delivered hot water suits the household's actual daily demand.
Solar PV & Time-of-Use Homes
Schedule Mode can target preferred heating periods such as daytime solar production or lower-cost time-of-use windows.
Owners Wanting App Visibility
The Thermann Control app provides greater visibility over energy consumption, operating mode and heating schedules than a conventional electric tank.
Is the Thermann Smart Electric 125L Right for My Home?
A Good Choice If...
You want familiar electric storage with app control, scheduling and energy-use visibility, and the 125L delivery capacity suits your demand.
Consider Another Option If...
Your household regularly uses substantially more hot water than the 125L class can provide, or smart control offers little value for the way your electricity supply operates.
JR Should Check First If...
Your existing tank uses controlled-load power, the Wi-Fi signal is weak at the water-heater location, water quality is unusual or the electrical circuit may not suit the selected element size.
125L Delivery vs 130L Storage Capacity
Thermann's current specification distinguishes between the tank's physical storage volume and its rated hot-water delivery.
Storage Capacity
The physical tank stores approximately 130 litres of water.
Hot-Water Delivery
The model is classified and marketed as a 125L system based on its published hot-water delivery.
Thermann currently guides the 125L model for approximately 3–4 people on continuous supply and 3 people on off-peak supply. Household behaviour can shift those numbers substantially, so capacity should still be matched to real usage.
How the Thermann Smart 125L Works
The Thermann Smart is still fundamentally an electric storage water heater. Hot water is stored in the tank and drawn from the top when an outlet is opened. Cold water enters at the bottom to replace it.
When the water around the electric element falls below the control temperature, the element heats the stored water. The difference from a standard electric tank is that the Smart Electric platform adds connected controls that allow the heating schedule and operating mode to be managed more deliberately.
How it works: stored hot water is drawn from the top → cold water enters the tank → the electric element reheats the tank according to the selected mode, tariff availability and control settings.
Thermann Control App & Smart Modes
Manual Mode
Provides direct control and can allow a lower stored-water setting while retaining Thermann's antibacterial-cycle protection.
Eco Mode
Uses machine learning to analyse usage patterns and minimise unnecessary heating for suitable flat-rate households.
Holiday Mode
Designed for periods where normal hot-water use is not expected, such as holidays or an unoccupied property.
Schedule Mode
Allows heating periods to be scheduled around household routines, solar PV availability or time-of-use tariffs.
Key Features of the Thermann Smart Electric 125L
Built-In Wi-Fi
Connects the water heater to the Thermann Control app when suitable 2.4GHz Wi-Fi coverage is available.
Energy & Cost Visibility
The app can display energy use and associated power-cost information to help owners understand when the system is consuming electricity.
Smart Scheduling
Heating can be scheduled around household routines, solar generation or applicable time-of-use pricing.
Antibacterial Cycle
If stored water remains below 62°C, the system can perform an automatic cycle that heats the tank to 62°C for 32 minutes every seven days.
Hard-Water Options
Thermann offers hard-water variants of the 125L models using an alternative anode arrangement for applicable higher-TDS water supplies.
Dual-Hand Connections
The current 125L specification provides connection flexibility to help with suitable replacement layouts.
Thermann Smart Electric 125L Specifications
| Brand | Thermann |
| Product Range | Smart Electric Storage |
| Hot-Water Delivery | 125L |
| Actual Storage Capacity | 130L |
| Heating Configuration | Single electric element |
| Available Element Sizes | 1.8kW, 2.4kW or 3.0kW |
| 1.8kW Recovery | 31L/hr at a 50°C temperature rise |
| 2.4kW Recovery | 41L/hr at a 50°C temperature rise |
| 3.0kW Recovery | 51.6L/hr at a 50°C temperature rise |
| Height | 1090mm |
| Diameter | 530mm |
| Outlet Height | 865mm |
| Inlet Height | 190mm |
| Electrical Entry Height | 135mm |
| Empty Weight | 51kg |
| Water Connections | RP 3/4 / DN20 hot and cold |
| Maximum Direct Water Supply Pressure | 800kPa before pressure reduction is required |
| PTR Valve Rating | 1000kPa / 99°C |
| Electrical Supply | Single-phase 230–240V AC |
| Wi-Fi | 2.4GHz network required for connected features |
| Manufacturer Continuous-Supply Guide | Approximately 3–4 people |
| Manufacturer Off-Peak Guide | Approximately 3 people |
What Is Required to Install the Thermann Smart 125L?
Flat, solid supporting base capable of supporting the filled storage system.
Suitable electrical circuit matched to the selected 1.8kW, 2.4kW or 3.0kW element.
230–240V single-phase supply installed in accordance with applicable electrical requirements.
Water pressure assessed with pressure reduction fitted where supply can exceed or fluctuate beyond 800kPa.
PTR drainage installed continuously downward to an appropriate discharge point.
Temperature control provided to applicable personal-hygiene outlets in accordance with current plumbing requirements.
Service clearance above the tank including access for the sacrificial anode through the top cover.
Safe tray where required indoors if leakage could cause property damage.
Plinth in wet conditions where required by the manufacturer installation guidance.
2.4GHz Wi-Fi signal at the tank if full Thermann Control app functionality is required.
What's Included With Thermann Smart 125L Installation?
Standard Installation
The selected JR installation package defines the standard plumbing, electrical and installation work included where existing site conditions suit the package.
Commissioning
The heater is filled, connected and checked for normal operation, with the appropriate system settings confirmed for the completed scope.
Possible Additional Work
Electrical circuit changes, pressure reduction, tempering, drainage, relocation, cabinetry work, access issues or other non-standard site conditions can change the final scope.
How Much Does Thermann Smart 125L Installation Cost?
Use JR's live product and installation selector above for current supplied-and-installed pricing. This keeps current package pricing, installation type and availability connected to the live Shopify product.
A straightforward replacement can have a different scope from a relocation, switchboard or circuit upgrade, controlled-load change, new tempering arrangement or installation requiring pressure-control work.
If the property conditions fall outside the standard package, the additional work should be confirmed against the actual site rather than hard-coded into this product description.
Thermann Smart Electric 125L Installation Brisbane
JR Gas & Water supplies and installs the Thermann Smart Electric 125L across eligible Brisbane service areas for suitable electric-storage replacements and upgrades.
For Brisbane homes, useful checks include the existing electrical tariff, circuit capacity, pressure-control arrangement, available tank footprint and whether a reliable 2.4GHz Wi-Fi signal reaches the water-heater location.
If the property has solar PV or a time-of-use tariff, the Smart Electric platform can provide additional scheduling flexibility compared with a conventional electric tank.
Thermann Smart Electric 125L Installation Gold Coast
JR Gas & Water also installs the Thermann Smart 125L across eligible Gold Coast service areas.
Where the tank is installed in an exposed or wet area, base condition, drainage, corrosion environment and the manufacturer's plinth guidance should be considered as part of the finished installation.
Water quality should also be considered rather than simply describing every Smart Electric tank as universally “hard-water ready”. Thermann provides dedicated hard-water variants where the water conditions justify them.
Can the Thermann Smart 125L Replace My Existing System?
Replacing Electric Storage
This can be the most direct pathway where tank dimensions, plumbing, circuit capacity, pressure control and the existing installation location suit the Smart 125L.
Replacing a Smaller Electric Tank
Moving up in size can require additional floor space, changed pipework and confirmation that the electrical circuit suits the selected element.
Replacing Gas Storage
A gas-to-electric conversion requires appropriate electrical provision and can involve different plumbing, temperature-control and decommissioning work.
Replacing a Heat Pump
A heat-pump-to-electric conversion may be physically simpler in some locations but changes the operating technology and energy-use profile substantially.
Thermann Smart 80L vs 125L vs 160L
| Specification | Smart 80L | Smart 125L | Smart 160L |
|---|---|---|---|
| Hot-Water Delivery | 80L | 125L | 160L |
| Actual Storage | 88L | 130L | 161L |
| Height | 925mm | 1090mm | 1315mm |
| Diameter | 490mm | 530mm | 530mm |
| Empty Weight | 41kg | 51kg | 59kg |
| Manufacturer Continuous-Supply Guide | 2–3 people | 3–4 people | 3–5 people |
| Element Options | 1.8 / 2.4 / 3.0kW | 1.8 / 2.4 / 3.0kW | 1.8 / 2.4 / 3.0kW |
The right size depends on actual hot-water demand and electricity arrangement rather than occupant count alone. Longer showers, high-flow fixtures and clustered morning or evening demand can justify moving up a size.
Recovery, Energy Use & Smart Scheduling
Element size determines how quickly the tank can recover after hot water is used. Thermann publishes recovery rates of 31L/hr for 1.8kW, 41L/hr for 2.4kW and 51.6L/hr for 3.0kW, each measured at a 50°C temperature rise.
A larger element does not change the tank's stored capacity. It changes how quickly electrical energy can be added back into the water after use.
The smart controls can be particularly useful where the property has solar PV or a time-of-use tariff because heating can be scheduled into preferred periods. Actual savings depend on tariffs, solar availability, usage and how the water heater is configured.
Smart-electric takeaway: the main advantage is not that the tank uses a fundamentally different heating method; it is that the standard electric-storage heating process can be scheduled and monitored more intelligently.
Thermann Smart Electric 125L Installation FAQs
How much does Thermann Smart 125L installation cost?
Use JR's live product and installation selector above for current pricing. Final scope depends on the existing tank, electrical circuit, tariff, plumbing, pressure control, drainage and installation position.
Is the Thermann Smart 125L actually a 125L tank?
Thermann publishes approximately 130L physical storage capacity and 125L hot-water delivery. The system is marketed in the 125L class based on delivered hot-water capacity.
How many people does the Thermann Smart 125L suit?
Thermann's current guide lists approximately 3–4 people on continuous electrical supply and 3 people on off-peak supply. Real suitability depends on shower length, fixture flow and usage patterns.
What element sizes are available?
The current manufacturer range lists 1.8kW, 2.4kW and 3.0kW single-element versions for the Smart 125L.
How fast does the Thermann Smart 125L recover?
Thermann publishes 31L/hr at a 50°C rise for the 1.8kW element, 41L/hr for 2.4kW and 51.6L/hr for 3.0kW.
Can I control the system from my phone?
Yes. With compatible Wi-Fi connectivity, the Thermann Control app can manage modes and schedules and display energy-use and power-cost information.
Does the Thermann Smart work on 5GHz Wi-Fi?
No. Thermann specifies a 2.4GHz Wi-Fi network for the Smart Electric connection.
Will the smart functions work on off-peak power?
The heater can operate with different electricity arrangements, but full app functionality requires power and Wi-Fi at the water heater. When an interrupted controlled-load supply removes power, remote communication will not be available during that period.
What does Eco Mode do?
Thermann states that Eco Mode uses machine learning to analyse usage patterns and optimise heating while keeping unnecessary heating to a minimum.
Is there a hard-water version?
Yes. Thermann publishes hard-water variants across the 125L element options. The appropriate version should be chosen according to the property's actual water quality rather than assumed for every Brisbane or Gold Coast property.
Can the Thermann Smart 125L be installed indoors?
Thermann permits electric-storage installation indoors. A properly drained safe tray is required where water leakage could cause property damage, and suitable service access must be maintained.
What warranty does the Thermann Smart 125L have?
For a qualifying single-family dwelling, Thermann publishes 10 years on the tank, three years parts coverage on the Wi-Fi module, connecting cable, thermostat and element, and one year on other parts and labour, subject to the full manufacturer warranty terms.
Thermann Smart 125L Warranty & Maintenance
10-Year Tank Warranty
Thermann publishes a 10-year tank warranty for qualifying single-family-dwelling installations, subject to all manufacturer conditions.
3-Year Selected Parts
The Wi-Fi module, connecting cable, thermostat and element receive three years parts coverage under the current manufacturer warranty.
1-Year Other Parts & Labour
Other parts including items such as the PTR valve and anode are covered for one year under the applicable manufacturer terms.
Thermann recommends operating the PTR valve easing lever every six months. Its current manual also recommends a licensed five-year service including PTR replacement, anode replacement, inspection of any expansion-control valve, tank flushing and electrical-condition checks.
Where Total Dissolved Solids exceed 600mg/L, Thermann recommends that major service every three years instead. Hard-water variants are also available for applicable water supplies.
Why Choose JR Gas & Water for Thermann Smart 125L Installation?
JR Gas & Water provides hot-water supply, replacement and installation across eligible Brisbane, Gold Coast and surrounding South East Queensland areas.
For a Thermann Smart Electric system, correct tank sizing, tariff arrangement, electrical circuit, water pressure, temperature control, drainage, installation access and Wi-Fi coverage all matter to the finished result.
JR can assess the live installation pathway around the existing system rather than assuming every 125L electric replacement has identical plumbing and electrical requirements.
Compare Thermann & Smart Electric Hot Water Options
These are current JR Gas & Water main-menu destinations.
Install the Thermann Smart Electric 125L With JR Gas & Water
The Thermann Smart 125L is designed for households wanting compact electric storage with app control, flexible heating schedules, energy-use visibility and a choice of 1.8kW, 2.4kW or 3.0kW recovery.
The main checks are whether 125L of delivered hot water suits the household, which element matches the electrical circuit and recovery needs, whether continuous power is available for the desired smart functionality, and whether normal or hard-water configuration is appropriate.
Use JR's live product and installation area above for current product availability, installation-package pricing and booking options.
Your electric storage hot water system is built to provide years of reliable hot water, but like any major household appliance, it requires regular maintenance to remain safe, efficient and covered under the manufacturer's warranty.
Many manufacturers specify routine maintenance throughout the life of the system. Following these recommendations helps maximise the lifespan of the unit, maintain safe operation and reduce the likelihood of unexpected breakdowns.
Homeowner Maintenance – Every 6 Months
Every six months, homeowners should carefully operate the Pressure & Temperature Relief (PTR) Valve and Expansion Control Valve (ECV) (where fitted).
This simple maintenance helps:
- Confirm the safety valves are operating correctly.
- Flush away mineral deposits that can cause the valves to seize.
- Prevent excessive pressure from building inside the tank.
- Extend the life of the safety valves.
Why is this important?
Over time, minerals naturally found in water can build up inside the valves. If they are never operated, they may become stuck or fail when they're needed most.
A seized PTR or ECV valve can lead to:
- Excessive pressure inside the tank.
- Continuous leaking from the valve.
- Reduced system efficiency.
- Premature component failure.
- Potential safety risks.
Important: Always follow your manufacturer's instructions when operating the valves, as hot water will discharge during testing. If you're unsure or unable to perform this maintenance safely, contact a licensed plumber.
JR 6-Month Hot Water Health Check
Recommended Service – $99
While homeowner maintenance is important, a professional inspection provides additional peace of mind and can identify issues long before they become expensive repairs.
Our JR 6-Month Hot Water Health Check includes:
- Inspection for water leaks and corrosion.
- Testing of the PTR valve.
- Testing of the ECV (where fitted).
- Checking electrical operation.
- Inspecting wiring and electrical connections.
- Checking thermostat operation.
- Inspecting the element for signs of failure (where possible).
- Inspecting insulation and pipework.
- Checking for unusual noises or signs of sediment build-up.
- Confirming correct operation and water heating performance.
- Identifying any components showing signs of wear.
Service Price: $99
Regular inspections help detect small problems early, reducing the likelihood of unexpected breakdowns and helping maximise the life of your hot water system.
Recommended 5-Year Major Service
Current Price: $449
Most electric storage hot water manufacturers recommend replacing several key components approximately every five years to maintain reliable operation and protect the storage tank.
Our comprehensive 5-Year Service includes:
- Replacement of the sacrificial anode.
- Replacement of the Pressure & Temperature Relief (PTR) Valve.
- Replacement of the Expansion Control Valve (ECV).
- Full inspection of the hot water system.
- Electrical safety and operational testing.
- Inspection of pipework, valves and fittings.
- Leak and corrosion inspection.
- System performance testing.
Why These Components Matter
Sacrificial Anode
The sacrificial anode protects the steel tank from internal corrosion.
Instead of the tank rusting, the anode slowly corrodes over time. Once it has been consumed, the tank itself begins to rust from the inside, often leading to leaks and complete tank failure.
Replacing the anode is one of the most effective ways to extend the life of a storage hot water system.
Pressure & Temperature Relief (PTR) Valve
The PTR valve is one of the most important safety devices on your hot water system.
It automatically releases water if pressure or temperature inside the tank becomes too high, protecting both the system and your home.
Over time, scale and mineral deposits can prevent the valve from operating correctly, making regular testing and replacement essential.
Expansion Control Valve (ECV)
The ECV manages pressure created as water expands during heating.
A correctly functioning ECV:
- Reduces stress on the storage tank.
- Protects plumbing components.
- Helps extend the life of the hot water system.
- Reduces unnecessary water discharge through the PTR valve.
If Your Hot Water System Isn't Working
Before arranging a service, there are a few simple checks you can perform:
- Ensure the power is switched on at the electrical switchboard.
- Check whether the hot water circuit breaker or safety switch (RCD) has tripped.
- Confirm the isolation switch near the hot water system is turned on.
- Check whether your electricity supplier has scheduled an off-peak interruption.
- Look for obvious water leaks around the system.
- Check whether water is continuously flowing from the PTR or ECV valve.
- Listen for unusual noises such as excessive boiling, rumbling or banging.
- Confirm the system has had sufficient time to reheat after heavy water usage.
If your system still isn't producing hot water, contact JR Gas & Water for professional diagnosis and repair.
General Signs Your System May Need Attention
Arrange a service if you notice:
- Water leaking from the tank.
- Constant dripping from relief valves.
- Rust-coloured or dirty hot water.
- Reduced hot water capacity.
- Water taking much longer to heat.
- Unusual noises during heating.
- Visible corrosion.
- Fluctuating water temperature.
- Repeated electrical trips.
Early repairs are often significantly less expensive than replacing a failed hot water system.
Protect Your Warranty & Maximise System Life
Regular maintenance not only helps keep your hot water system operating safely and efficiently—it can also assist in meeting manufacturer maintenance requirements.
Ignoring recommended servicing may result in:
- Premature tank corrosion.
- Seized or leaking safety valves.
- Reduced efficiency and higher running costs.
- Unexpected loss of hot water.
- Avoidable repair costs.
- Shortened system lifespan.
- Possible reduction or loss of manufacturer warranty, depending on the manufacturer's maintenance requirements.
A small investment in preventative maintenance can add years to the life of your hot water system and help avoid the inconvenience and expense of an unexpected replacement.
ZipPay – 6-Month Interest-Free on All Products
ZipPay allows you to buy now and pay later, offering flexible, interest-free payments for up to 6 months on all JR products. It’s easy to set up, and you can customize your repayment schedule to suit your budget. Payments can be made weekly, fortnightly, or monthly, with a $6 fee if the balance isn’t paid off by the due date.
Humm – Up to 12 Months Interest-Free
Humm provides interest-free payment plans on purchases up to $30,000, perfect for both small and large buys. For items over $2,000, you can spread payments over 12 months. Humm also offers flexibility in scheduling payments based on when you get paid
Afterpay – 8 Weeks, No Interest
With Afterpay, spread the cost of purchases across four equal installments, due every two weeks, over an 8-week period. There’s no interest, and as long as payments are made on time, there are no fees. Perfect for purchases between $100 and $1,500
Plenti Finance – For Reclaim Systems Only
Plenti Finance is available exclusively for Reclaim Energy systems. This option offers tailored repayment terms with competitive interest rates, helping make eco-friendly choices more affordable. For more detailed information on Plenti’s terms and eligibility for Reclaim systems, visit the Reclaim Energy finance page
If you're in Queensland and considering a new electric hot water system, JR Gas & Water is the company to choose. Here's why:
Experience and Expertise: JR Gas & Water has over 10 years of experience in the gas and plumbing industry. Their team of licensed and insured professionals is highly skilled and knowledgeable about all aspects of electric hot water system installation, maintenance, and repair. They can provide expert advice on the best system for your needs and ensure a smooth installation process.
Quality Products: JR Gas & Water uses only high-quality products from trusted brands to ensure your electric hot water system is reliable and efficient. They also offer a range of options to suit different budgets and requirements.
Competitive Pricing: JR Gas & Water offers competitive pricing for their electric hot water systems, ensuring that you get a great value for your investment. They also provide a detailed quote upfront, so there are no surprises or hidden costs.
Customer Service: JR Gas & Water is committed to providing excellent customer service. They are always available to answer any questions or concerns you may have and are committed to ensuring your satisfaction.
Local Business: JR Gas & Water is a locally owned and operated business in Queensland. By choosing them for your electric hot water installation, you are supporting a local business and contributing to the local economy.
Warranty and Guarantee: JR Gas & Water provides a warranty and guarantee on all their products and services, giving you peace of mind knowing that your system is covered in case of any issues.
Energy Efficiency: Electric hot water systems can be energy efficient, and JR Gas & Water can help you choose the right system for your needs. They can provide advice on energy-saving features and options, such as timers and thermostats, to help you save on your energy bills.
Safety: JR Gas & Water is committed to safety and ensuring that all installations are done to the highest safety standards. They are also familiar with local safety regulations and requirements, ensuring that your electric hot water system is installed safely and in compliance with all relevant codes.
JR Gas & Water is a reliable and experienced choice for your electric hot water system installation in Queensland. With a commitment to quality products, competitive pricing, excellent customer service, and safety, they can help you make the switch to a more efficient and cost-effective solution for your hot water needs. Contact them today to learn more about their services and how they can help you.