JR GAS & WATER INSTALLER ASSESSMENT
Our Instantaneous Gas 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, mounting, gas and water connections, commissioning and ongoing support, rather than a repeat of the specification sheet.
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JR GAS & WATER LOCAL INSTALLATION
Local Hot Water Installation Areas
View all hot water service areas🏷️ Brand: Vulcan
🔢 Model Number: Duomax 26
📦 Volume: L
📏 Width: mm
📐 Height: mm
🌍 Manufactured In:
🛠️ Heat Exchange Material:
🛡️ Cylinder/Heat-Exchange Warranty: Years
🔇 Noise Level: dBa
⚖️ Dry Weight: kg
📡 WiFi Controller:
⏲️ Built-In Timer:
💡 LED/LCD Status Indicator:
📊 Coefficient of Performance (COP):
⚡ Energy Source:
IMPORTANT - Default supply is Natural Gas — please leave a note at checkout if LPG is required where available.
VULCAN DUOMAX CONTINUOUS FLOW GAS HOT WATER
Vulcan DuoMax 26 Installation Brisbane & Gold Coast
The Vulcan DuoMax 26 is an outdoor gas continuous-flow hot water system designed for households wanting strong on-demand hot-water delivery without a storage cylinder.
Vulcan rates the DuoMax 26 at 26 litres per minute with a 25°C temperature rise, with a 6-star gas energy rating and nominal gas consumption of 199MJ/h. Current Australian variants are available for both Natural Gas and Propane, with separate 50°C and 60°C configurations.
The manufacturer positions the 26L model around 2–2.5 bathrooms. Actual suitability depends on incoming-water temperature, shower flow, simultaneous outlet use, water pressure and the capacity of the property's gas supply.
Quick answer: the Vulcan DuoMax 26 is a 6-star outdoor continuous-flow gas system rated at 26L/min at a 25°C rise. It uses 199MJ/h nominal gas input, needs at least 120kPa water supply pressure, starts operating from around 2L/min flow and measures 520 × 355 × 188mm.
Vulcan DuoMax 26 at a Glance
26L/min
Rated Hot-Water Flow
Published flow at a 25°C temperature rise, subject to incoming-water temperature, pressure and correct pipe sizing.
6 Star
Gas Energy Rating
Continuous-flow operation heats water when required rather than maintaining a hot storage cylinder.
199MJ/h
Gas Input
The property's gas line and regulator arrangement need to support the appliance together with other connected gas loads.
16kg
Compact Outdoor Unit
The appliance measures approximately 520mm high × 355mm wide × 188mm deep.
Who Is the Vulcan DuoMax 26 Best For?
Two-Bathroom Homes
Vulcan's published sizing guide positions the 26L class around approximately 2–2.5 bathrooms, subject to actual simultaneous use.
Existing Instant-Gas Replacements
The DuoMax 26 can suit replacement of another continuous-flow gas system where the existing gas supply, water pressure, power and wall position remain appropriate.
Natural Gas or LPG Homes
Separate factory Natural Gas and Propane versions are available, allowing the correct appliance to be selected for the property's gas supply.
PRODUCT SUITABILITY
Is the Vulcan DuoMax 26 Right for My Home?
A Good Choice If...
You already have a suitable gas supply, want a compact wall-mounted continuous-flow system and need more capacity than a smaller 16L or 20L class appliance.
Consider Another Option If...
Your household regularly runs several high-flow hot-water outlets simultaneously, the property has very high peak demand or substantial new gas infrastructure would be required solely for hot water.
JR Should Check First If...
You are upgrading from a much smaller gas unit, converting from electric or solar, relocating the system, changing gas type or are unsure whether the existing gas line can support 199MJ/h.
How Does the Vulcan DuoMax 26 Work?
The DuoMax 26 heats water as it passes through the appliance instead of storing a heated volume in a cylinder.
When a hot-water outlet opens and sufficient water flow is detected, electronic controls activate the burner. Heat from the burner is transferred through the heat exchanger into the moving water, with gas input adjusted to maintain the appliance's target outlet temperature.
When hot-water demand stops, the burner shuts down. Vulcan publishes a minimum operating flow of approximately 2L/min.
How it works: open a hot tap → sufficient flow activates the unit → the burner heats water moving through the heat exchanger → electronic controls regulate output → the burner stops when demand ends.
Vulcan DuoMax 26 50°C vs 60°C Models
| Configuration | Natural Gas | Propane / LPG | Published Temperature |
|---|---|---|---|
| 50°C DuoMax 26 | 246A26NF | 246A26PF | Factory preset maximum 50°C |
| 60°C DuoMax 26 | 244A26NF | 244A26PF | 60°C market configuration |
50°C or 60°C matters: Vulcan states that the factory 50°C models are designed to supply water at no more than 50°C in accordance with their applicable certification, although some plumbing applications can still require temperature control. The 60°C version requires a compliant tempering arrangement for applicable personal-hygiene outlets.
Key Features of the Vulcan DuoMax 26
Smart Electronic Control
The appliance automatically adjusts burner operation in response to water flow and the required outlet-temperature setting.
Digital OK Monitor
Vulcan's current DuoMax platform includes an onboard digital display used for operating information and service diagnostics.
Overheat Protection
The appliance incorporates automatic over-temperature protection designed to shut the system down when abnormal overheating is detected.
Low Minimum Flow
A published minimum operating flow of 2L/min helps the appliance operate with lower-flow outlets where the overall installation remains suitable.
Frost Protection
The DuoMax platform incorporates frost protection for suitable operating conditions, subject to the appliance remaining correctly powered and installed.
Made in Japan
Vulcan identifies the DuoMax continuous-flow platform as manufactured in Japan.
Vulcan DuoMax 26 Technical Specifications
| Brand | Vulcan |
| Range | DuoMax Gas Continuous Flow |
| System Type | Outdoor continuous-flow gas water heater |
| 50°C Natural Gas Model | 246A26NF |
| 50°C LPG / Propane Model | 246A26PF |
| 60°C Natural Gas Model | 244A26NF |
| 60°C LPG / Propane Model | 244A26PF |
| Flow Rate | 26L/min at a 25°C temperature rise |
| Manufacturer Bathroom Guide | Approximately 2–2.5 bathrooms, subject to actual demand and operating conditions |
| Gas Energy Rating | 6 stars |
| Nominal Gas Consumption | 199MJ/h |
| Minimum Operating Flow | 2L/min |
| Minimum Water Supply Pressure | 120kPa |
| Maximum Water Supply Pressure | 1000kPa |
| Cold Water Connection | R 3/4 |
| Hot Water Connection | R 3/4 |
| Gas Connection | R 3/4 |
| Height | 520mm |
| Width | 355mm |
| Depth | 188mm |
| Empty Weight | 16kg |
| Installation Position | Outdoor installation only |
| Manufacturing | Japan |
Flow-rate context: 26L/min is measured at a 25°C temperature rise. Real delivered flow at the required outlet temperature changes with incoming-water temperature, water pressure, pipe sizing and simultaneous household demand.
INSTALLATION REQUIREMENTS
What Is Required to Install the Vulcan DuoMax 26?
Correct Natural Gas or Propane model selected to match the property's actual gas supply.
Gas pipework sized for 199MJ/h while accounting for other connected gas appliances.
Water pressure within the manufacturer's range, with pressure control added where required.
Outdoor installation position satisfying current flue-terminal and gas-appliance clearance requirements.
Suitable supporting wall or frame so the unit is securely mounted.
Correct hot, cold and gas connections sized for the finished installation.
Suitable electrical supply for the appliance's electronic controls and protection systems.
Clearance from windows, doors and openings assessed against the current installation requirements.
Correct 50°C or 60°C plumbing arrangement selected for the intended outlets.
Future service access retained around the appliance.
Do not size the job from the old heater alone: an existing smaller continuous-flow or gas-storage system may have a lower gas input. Moving to a 199MJ/h appliance can require changes to gas pipework, regulator capacity or the final installation position.
What's Included With Vulcan DuoMax 26 Installation?
Selected Installation Package
The JR installation option chosen in the live selector above defines the standard labour and materials included for that particular replacement or conversion pathway.
Commissioning
The completed installation is commissioned with gas, water and appliance operation checked for the installed scope.
Possible Additional Work
Gas-main upgrades, new power provision, tempering, pressure control, relocation, access work or substantial pipe alterations can change the final installation scope.
How Much Does Vulcan DuoMax 26 Installation Cost?
Use JR's live product and installation selector above for current supplied-and-installed pricing. Pricing should remain connected to the selected installation package rather than being duplicated into this long-form description.
A like-for-like replacement of a suitably sized continuous-flow gas unit can have a very different scope from converting electric storage, replacing gas storage, installing new gas pipework or relocating the water heater.
JR's live product currently defaults to Natural Gas and asks customers to identify LPG requirements where the LPG version is needed and available.
BRISBANE INSTALLATION
Vulcan DuoMax 26 Installation Brisbane
JR Gas & Water supplies and installs the Vulcan DuoMax 26 across eligible Brisbane service areas for suitable Natural Gas and LPG properties.
For Brisbane replacements, the gas supply is one of the most important checks. An older continuous-flow water heater or gas-storage system may have substantially lower gas input than the DuoMax 26's 199MJ/h requirement.
The existing outdoor wall position also needs to meet current appliance-clearance, flue-discharge, water-pressure and servicing requirements rather than simply being reused because an older heater was previously mounted there.
GOLD COAST INSTALLATION
Vulcan DuoMax 26 Installation Gold Coast
JR Gas & Water also installs the Vulcan DuoMax 26 across eligible Gold Coast service areas for suitable continuous-flow replacements and gas hot-water upgrades.
The Gold Coast's warmer incoming-water conditions can affect the usable flow available from a continuous-flow system because the published 26L/min rating is measured at a specific 25°C temperature rise.
Final positioning should also consider outdoor exposure, flue clearance, surrounding openings, gas supply, water pressure and future access for servicing.
Can the Vulcan DuoMax 26 Replace My Existing Hot Water System?
Replacing Instant Gas
Often the most direct pathway, but the existing gas line, power, water connections and flue clearances still need to support the DuoMax 26.
Replacing Gas Storage
Moving from gas storage to continuous flow generally requires a suitable outdoor wall position and can require pipework, power and gas-supply changes.
Replacing Electric Storage
An electric-to-gas conversion requires an appropriate gas supply in addition to new continuous-flow plumbing and electrical provision.
Replacing Solar Hot Water
Solar replacement can involve the existing tank, collectors, pipework and booster configuration, so the scope can be substantially different from a standard gas replacement.
Vulcan DuoMax 20 vs DuoMax 26
The DuoMax 20 and DuoMax 26 share the same compact platform dimensions, but the 26 provides greater rated flow and requires a higher gas input.
| Specification | DuoMax 20 | DuoMax 26 |
|---|---|---|
| Rated Flow at 25°C Rise | 20L/min | 26L/min |
| Manufacturer Bathroom Guide | Approximately 1.5–2 bathrooms | Approximately 2–2.5 bathrooms |
| Gas Energy Rating | 6 stars | 6 stars |
| Nominal Gas Consumption | 157MJ/h | 199MJ/h |
| Minimum Operating Flow | 2L/min | 2L/min |
| Dimensions | 520 × 355 × 188mm | 520 × 355 × 188mm |
| Empty Weight | 16kg | 16kg |
| Main Difference | Lower rated flow with lower gas demand. | Higher rated flow for stronger simultaneous demand. |
Vulcan DuoMax 26 Efficiency & Hot-Water Performance
The DuoMax 26 has a 6-star gas energy rating and heats water only when there is active demand. This avoids the normal standing heat loss associated with maintaining hot water in a storage cylinder.
The published 26L/min figure is based on a 25°C temperature rise. For example, colder incoming water requires the appliance to add more heat to reach the same outlet temperature, which affects the flow it can sustain.
Real household performance therefore depends on the season, shower-head flow rates, selected outlet temperature, water pressure and how many hot-water outlets are being used together.
Performance takeaway: 26L/min is a rated operating point, not a promise that every home can run every hot-water fixture simultaneously. Correct sizing should be based on expected peak flow and incoming-water conditions.
Vulcan DuoMax 26 Warranty & Maintenance
10 Years Heat Exchanger Parts
For qualifying domestic non-commercial installations, Vulcan publishes 10 years parts coverage on the heat exchanger, subject to its full warranty conditions.
3 Years Heat Exchanger Labour
The published domestic warranty provides three years labour coverage on the heat exchanger.
3 Years Other Components
Vulcan publishes three years parts and labour on other components for qualifying domestic installations, subject to the complete warranty terms.
The current Vulcan owner and installation documentation should remain the primary maintenance reference for the installed model. Keeping the water heater powered where required for frost protection, maintaining clear airflow and flue discharge, and addressing abnormal operation or displayed faults promptly are important ownership considerations.
Warranty conditions apply: installation, gas supply, power supply, water quality and ongoing maintenance all need to comply with Vulcan's current requirements for warranty eligibility.
COMMON QUESTIONS
Vulcan DuoMax 26 Installation FAQs
How much does Vulcan DuoMax 26 installation cost?
Use JR's live product and installation selector above for current pricing. Final cost depends on whether the job is a like-for-like replacement, gas-line upgrade, conversion, relocation or another installation pathway.
How much hot water does the Vulcan DuoMax 26 provide?
Vulcan rates the DuoMax 26 at 26L/min with a 25°C temperature rise. Actual flow at the required outlet temperature depends on incoming-water temperature, pressure, pipe sizing and simultaneous demand.
How many bathrooms does the Vulcan DuoMax 26 suit?
Vulcan's published guide positions the 26L model around approximately 2–2.5 bathrooms. Actual sizing should be based on how many hot-water outlets are likely to operate together rather than bathroom count alone.
Is the Vulcan DuoMax 26 available in LPG?
Yes. Separate Propane/LPG versions are available for both the 50°C and 60°C DuoMax 26 configurations. The appliance must match the property's actual gas type.
What are the 50°C Vulcan DuoMax 26 model numbers?
The 50°C versions are 246A26NF for Natural Gas and 246A26PF for Propane/LPG.
What are the 60°C Vulcan DuoMax 26 model numbers?
Current Australian listings identify the 60°C versions as 244A26NF for Natural Gas and 244A26PF for Propane/LPG.
Does the Vulcan DuoMax 26 need a tempering valve?
The 60°C configuration requires compliant temperature limitation for applicable personal-hygiene outlets. Vulcan's factory 50°C models are designed around a maximum 50°C delivery classification, although the finished plumbing arrangement must still comply with the requirements applying to the property.
What gas supply does the DuoMax 26 require?
Vulcan publishes nominal gas consumption of 199MJ/h. The gas pipework, meter or LPG regulator and other connected gas appliances need to be considered when confirming whether the property can support the unit.
What water pressure does the Vulcan DuoMax 26 need?
Vulcan publishes a minimum water supply pressure of 120kPa and maximum of 1000kPa for the DuoMax continuous-flow range.
Can the Vulcan DuoMax 26 replace a smaller gas unit?
Potentially. The higher 199MJ/h gas demand means the existing gas pipework still needs to be checked, even if the new appliance is being installed in the same position.
What warranty does the Vulcan DuoMax 26 have?
For qualifying domestic non-commercial installations, Vulcan publishes 10 years parts and three years labour on the heat exchanger, plus three years parts and labour on other components, subject to the full manufacturer warranty terms.
Can JR install the Vulcan DuoMax 26 in Brisbane or the Gold Coast?
JR Gas & Water supplies and installs continuous-flow gas hot-water systems across eligible Brisbane, Gold Coast and surrounding South East Queensland service areas. Final suitability depends on the gas supply, property and selected installation scope.
Why Choose JR Gas & Water for Vulcan DuoMax 26 Installation?
JR Gas & Water provides hot-water supply, replacement and installation across eligible Brisbane, Gold Coast and surrounding South East Queensland areas.
For the Vulcan DuoMax 26, correct sizing, gas capacity, fuel type, wall position, flue clearances, water pressure, plumbing, electrical supply and commissioning all matter to the finished installation.
JR can assess the existing system and selected installation pathway together rather than assuming every 26L continuous-flow replacement is a simple like-for-like swap.
COMPARE YOUR OPTIONS
Compare Gas Hot Water & Replacement Options
These are current JR Gas & Water Hot Water main-menu destinations.
READY TO INSTALL
Install the Vulcan DuoMax 26 With JR Gas & Water
The Vulcan DuoMax 26 is designed for suitable homes wanting 26L-class continuous-flow performance, Natural Gas or LPG availability, six-star gas efficiency and compact outdoor installation.
The key checks are whether 26L suits the home's peak demand, whether the correct 50°C or 60°C model is selected, whether the gas supply can support 199MJ/h and whether the proposed installation position complies with the current Vulcan requirements.
Use JR's live product and installation area above for current product configuration, installed pricing, package scope and booking availability.
🔥 Instant Gas Hot Water System Package Selection Guide
(Please rotate your mobile device for easier viewing)
Choosing the right instant gas hot water system package depends on your current setup, whether plumbing or gas upgrades are needed, and if any relocation or compliance work is required. Use this guide to compare package levels and find the best match for your home.
We know things don’t always go to plan — and most customers aren’t plumbers — so we’re flexible and happy to adjust your installation package if needed.
💡 Which Package Is Right for You?
IMPORTANT: All online packages are for EXTERNAL installations only. For internal installations, please request a quote.
✅ Base – For compliant replacements of existing identical EXTERNAL instant systems
Best for like-for-like swaps where the existing system is fully compliant and the same make/model/series. No gas line changes, electrical work, or plumbing alterations.
🧰 Example: Replacing a Rinnai B26 with a Rinnai B26 on the same wall with compliant gas supply.
✅ Silver – For minor upgrades
Includes small plumbing adjustments and a new valve kit. No gas line modifications or system disposal. Designed for customers on a budget upgrading to a slightly different model.
🧰 Example: Replacing a Rheem 26 with a Rinnai B26 where the gas line is compliant but pipework needs modifying to suit and valves need replacing for warranty.
🏆 Gold – Best Seller – For standard installations
Covers everything needed for a standard upgrade: removal of old unit, plumbing changes, valves, and a tempering valve.
🧰 Example: Upgrading from an old Bosch 16P Instant to a new Bosch 16H that requires a tempering valve, with full plumbing refresh and removal of old unit.
💰 Sapphire – Best Value – For installations requiring gas upgrades
Everything in the Gold package plus gas line upgrades or a new gas main from meter to unit to ensure safe and compliant installation.
🧰 Example: Switching from a smaller capacity like a 13L to a larger 26L instant system that needs a larger gas main and full plumbing setup.
✅ Diamond – For major gas plumbing overhauls
Adds extended gas runs, upgraded regulators or meter connections and a new power point. Ideal for homes switching to gas or where old systems were severely non-compliant.
🧰 Example: Changing from electric to gas in a home with no current gas line in the right location, requiring a full line upgrade.
✅ Platinum – The ultimate package
Includes everything: relocation, extensive plumbing, and full gas installation or rerouting. Ideal for complex installs or new system placements.
🧰 Example: Moving the hot water system to the opposite side of the home and running a new gas line with full setup and all compliance.
🏆 Package Comparison Guide
Here’s your revised Package Comparison Guide with the new line added as the third row, directly under “Existing System Must Be Same Type & Location”:
| Feature | Base | Silver | Gold 🏆 | Sapphire 💰 | Diamond | Platinum |
|---|---|---|---|---|---|---|
| ✅ Existing System Must Be Identical Make/Model as Purchase with Compliant Installation | ✅ | ❌ | ❌ | ❌ | ❌ | ❌ |
| ⚠️ Includes gas supply upgrade to suit larger capacity unit (e.g. 16L replaced with 16L or larger) | ❌ | ❌ | ❌ | ✅ | ❌ | ✅ |
| ✅ Existing System Removal & Form 4 (Compliance Certificate) | ✅ | ✅ | ✅ | ✅ | ✅ | ✅ |
| 🔧 Pipework Alterations | ❌ | ✅ | ✅ | ✅ | ✅ | ✅ |
| 🔧 Valve Kit | ❌ | ✅ | ✅ | ✅ | ✅ | ✅ |
| 📏 Pipework Included (m) | ❌ | 2m | 4m | 14m | 4m | 24m |
| 🧱 Support Base (if ground is soft/uneven) | ❌ | ❌ | ✅ | ✅ | ✅ | ✅ |
| 🗑️ FREE Old System Disposal (EXCLUDES ANY AND ALL ROOF MOUNTED COMPONENTS) | ❌ | ❌ | ✅ | ✅ | ✅ | ✅ |
| 🔧 Powerpoint | ❌ | ❌ | ❌ | ✅ | ✅ | ✅ |
| 🔥 Gas Line Upgrade / New Gas Main | ❌ | ❌ | ❌ | ✅ | ❌ | ✅ |
| 📦 System Relocation | ❌ | ❌ | ❌ | ❌ | ❌ | ✅ |
| ✅ Requires Compliant Existing Install | ✅ | ✅ | ❌ | ❌ | ❌ | ❌ |
🔧 Trusted Materials, Backed by Quality
We only use high-grade parts from reputable manufacturers:
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Valves – AVG, RMC, Rye Metal
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Copper Pipe – Kembla Type B, Crane
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PEX Plumbing – Ezipex
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Insulation – eFlex, K-Flex
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Brassware – Brasshards
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Gas Components – Bromic, EziPress, Viega
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Sealants – Loxeal
Let us know if you have any specific brands or components you’d like us to use.
🛠 Need Help Choosing?
Still unsure which package is right for your home?
The JR Gas & Water team is here to help.
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.