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Rinnai 400L Electric Hot Water System

Was $1,799.00, Now $1,429.00
Hot Water Outlet
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Add a Valve Kit1 option
AVG Quickie Installation Kit 15RCV
AVG Quickie Installation Kit 15RCV
$249.00
Purchase Valves Individually 12 options
AVG Quickie Installation Kit 15RCV
AVG Quickie Installation Kit 15RCV
$249.00
Duo Valve 15mm (Female)
Duo Valve 15mm (Female)
$49.00
Duo Valve 15mm (Male x Male)
Duo Valve 15mm (Male x Male)
$49.00
Expansion Control Valve (ECV) 1000kPa
Expansion Control Valve (ECV) 1000kPa
$79.00
Expansion Control Valve (ECV) 1200kPa
Expansion Control Valve (ECV) 1200kPa
$79.00
Expansion Control Valve (ECV) 600kPa
Expansion Control Valve (ECV) 600kPa
$79.00
Expansion Control Valve (ECV) 700kPa
Expansion Control Valve (ECV) 700kPa
$79.00
Expansion Control Valve (ECV) 850kPa
Expansion Control Valve (ECV) 850kPa
$79.00
Pressure Limiting Valve 15mm (Female)
Pressure Limiting Valve 15mm (Female)
$89.00
Pressure Limiting Valve 15mm (Male)
Pressure Limiting Valve 15mm (Male)
$89.00
Tempering Valve 15mm
Tempering Valve 15mm
$109.00
Tempering Valve 15mm (High Performance)
Tempering Valve 15mm (High Performance)
$149.00
Add Pipework & Insulation4 options
15mm Copper Tube
15mm Copper Tube
$20.00
Qty
15mm Insulation
15mm Insulation
$15.00
Qty
20mm Copper Tube
20mm Copper Tube
$40.00
Qty
20mm Insulation
20mm Insulation
$20.00
Qty
Add Brass Connecting Fittings14 options
15mm Brass Compression Elbow
15mm Brass Compression Elbow
$12.50
Qty
15mm Brass Compression Male Line
15mm Brass Compression Male Line
$7.50
Qty
15mm Brass Compression Union
15mm Brass Compression Union
$7.50
Qty
15mm Brass Compression x Female Elbow
15mm Brass Compression x Female Elbow
$12.50
Qty
15mm Brass Compression x Male Elbow
15mm Brass Compression x Male Elbow
$12.50
Qty
15mm Brass Hex Nipple
15mm Brass Hex Nipple
$7.50
Qty
20mm Brass Compression Elbow
20mm Brass Compression Elbow
$17.50
Qty
20mm Brass Compression Male Line
20mm Brass Compression Male Line
$12.50
Qty
20mm Brass Compression Union
20mm Brass Compression Union
$12.50
Qty
20mm Brass Compression x Female Elbow
20mm Brass Compression x Female Elbow
$17.50
Qty
20mm Brass Compression x Male Elbow
20mm Brass Compression x Male Elbow
$17.50
Qty
20x15mm Brass Compression Union
20x15mm Brass Compression Union
$7.50
Qty
20x15mm Brass Compression x Male Elbow
20x15mm Brass Compression x Male Elbow
$12.50
Qty
20x15mm Brass Hex Nipple
20x15mm Brass Hex Nipple
$7.50
Qty
Add Crimp Fittings8 options
15mm Copper Water Press Elbow
15mm Copper Water Press Elbow
$7.50
Qty
15mm Copper Water Press Joiner
15mm Copper Water Press Joiner
$7.50
Qty
15mm Copper Water Press Male Line
15mm Copper Water Press Male Line
$10.00
Qty
15mm Copper Water Press Tee
15mm Copper Water Press Tee
$10.00
Qty
20mm Copper Water Press Elbow
20mm Copper Water Press Elbow
$12.50
Qty
20mm Copper Water Press Joiner
20mm Copper Water Press Joiner
$12.50
Qty
20mm Copper Water Press Male Line
20mm Copper Water Press Male Line
$17.50
Qty
20mm Copper Water Press Tee
20mm Copper Water Press Tee
$17.50
Qty
Add Support Base3 options
600mm Flat Concrete Support Base
600mm Flat Concrete Support Base
$99.00
600mm Rippled Concrete Support Base
600mm Rippled Concrete Support Base
$99.00
Plastic Support Base (Pizza)
Plastic Support Base (Pizza)
$70.00
Add Sealants & Sundries2 options
Loxeal
Loxeal
$50.00
PTFE Thread Tape
PTFE Thread Tape
$2.50

Quick Specs & Benefits

  • Recommended Household Size: 8+ people
  • Make: Rinnai
  • Model: HFE400S
  • Volume: 400L
  • Maximum Warranty: 10 years
  • Height: 1820 mm
  • Width: 625 mm
  • Made In: China
  • Main Cylinder Material: Steel
Supply-only hot water systems available to eligible delivery areas
$25 flat rate standard shipping for eligible supply-only orders
90% of hot water orders delivered within 2 business days
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Rinnai Hotflo 400L Electric Hot Water System

The Rinnai Hotflo 400L Electric Hot Water System is available online from Hot Water Outlet as a supply-only electric storage water heater with metro delivery available in selected areas Australia wide.

Customers can purchase the Rinnai Hotflo 400L as a supply-only hot water system and request assistance arranging installation quotes after purchase through licensed local installers in selected metro regions.

The Rinnai Hotflo 400L electric storage water heater is the largest-capacity model in the Rinnai Hotflo electric storage range, designed for large families and high-demand households that need an abundant stored hot water supply. With 420L rated capacity, vitreous enamel lined steel tank, inbuilt anode protection, single or twin element configuration options, dual handed connections, internal or external installation suitability and a 10-year cylinder warranty, it is a strong choice for replacing an older large electric hot water system.

About the Rinnai Hotflo 400L Electric Water Heater

The Rinnai Hotflo 400L Electric Hot Water System is designed for big households that need reliable stored hot water without loss of pressure.

Rinnai positions the Hotflo 400L as the highest-capacity electric storage tank in the Hotflo range, making it a practical option for larger Australian families, shared homes, rental properties and homes with high daily hot water demand.

Although commonly referred to as a 400L electric hot water system, the listed rated capacity is 420L. This gives the system a large stored hot water reserve for homes where multiple showers, laundry use and kitchen hot water demand can occur close together.

Buy Rinnai Hotflo 400L Supply Only

Order the Rinnai Hotflo 400L Electric Hot Water System online from Hot Water Outlet with metro delivery available in selected areas across Australia.

This option is ideal if you already have a licensed plumber or electrician arranged and only need the unit supplied.

The supply-only product price includes the hot water system itself.

Installation, old system removal, disposal, valve kits, electrical work, plumbing alterations, compliance upgrades and additional site requirements are not included unless separately quoted.

Supply-only is best for customers searching for:

  • Rinnai Hotflo 400L price

  • Rinnai Hotflo 400L electric hot water system

  • Rinnai EHFA400 electric water heater

  • Rinnai 400L electric storage hot water system

  • Rinnai Hotflo 400L supply only

  • 400L electric hot water system supply only

  • Large electric storage hot water system

  • Rinnai electric water heater for sale

  • Large family electric hot water system

Installation Quotes Available After Purchase

Hot Water Outlet does not directly provide installation services.

After purchasing the Rinnai Hotflo 400L Electric Hot Water System, customers in selected metro areas may request assistance arranging installation quotes through licensed local plumbers and electricians.

Installation quote availability depends on:

  • service location

  • installer availability

  • existing system type

  • electrical suitability

  • plumbing suitability

  • access requirements

  • compliance requirements

Additional installation costs may apply for:

  • valve upgrades

  • electrical work

  • plumbing changes

  • pipework alterations

  • difficult access

  • base preparation

  • old system removal

  • disposal

  • compliance upgrades

Rinnai Hotflo 400L Delivery Brisbane

Hot Water Outlet offers metro delivery for the Rinnai Hotflo 400L Electric Hot Water System in selected Brisbane areas.

Customers can order online and request assistance arranging installation quotes after purchase where available.

Rinnai Hotflo 400L Delivery Gold Coast

Hot Water Outlet offers metro delivery for the Rinnai Hotflo 400L Electric Hot Water System in selected Gold Coast service areas.

Customers can purchase online and organise installation separately or request help arranging installation quotes after purchase.

Rinnai Hotflo 400L Delivery Sydney

Hot Water Outlet offers metro delivery for the Rinnai Hotflo 400L Electric Hot Water System in selected Sydney metro areas.

Customers can order online with installation quote assistance available after purchase in selected locations.

Rinnai Hotflo 400L Delivery Melbourne

Hot Water Outlet offers metro delivery for the Rinnai Hotflo 400L Electric Hot Water System in selected Melbourne metro areas.

Customers can purchase the system online and request help arranging installation quotes after delivery.

Is the Rinnai Hotflo 400L Right for Your Home?

The Rinnai Hotflo 400L Electric Hot Water System may be suitable if you are replacing a large electric storage water heater and want the biggest capacity option in the Rinnai Hotflo electric storage range.

It is commonly suited to larger family homes, shared homes, high-use households, rental properties, investment properties and homes with very high daily hot water demand.

Suitability depends on household size, shower length, hot water habits, climate, tariff setup, fixture flow rates, available installation space, plumbing condition, electrical connection and the ability of the existing location to suit a large tank.

This system may suit you if:

  • you are replacing an existing large electric storage hot water system

  • you want a 400L-class electric hot water unit

  • you need the largest capacity in the Rinnai Hotflo electric storage range

  • your household has high daily hot water demand

  • your household has around 8 or more people depending on usage

  • you want single or twin element configuration options

  • you want a vitreous enamel lined steel tank

  • you want inbuilt anode protection

  • you need internal or external installation suitability

  • your property has suitable access and installation space

  • your plumbing and electrical setup are suitable for the selected installation option

  • you prefer supply-only purchase flexibility

Extra work may be required if:

  • the system is being moved to a new location

  • existing valves are old, missing or non-compliant

  • extra pipework or drainage changes are needed

  • electrical upgrades are required

  • access is restricted

  • a compliant base, tray, drainage or insulation is required

  • the old system needs additional removal or disposal work

  • the selected element rating does not match the existing electrical setup

  • the existing water pressure requires valve or pressure control changes

  • a twin element model requires electrical work to suit the site

  • the existing location does not suit the larger tank size or filled weight

Key Features of the Rinnai Hotflo 400L

  • 400L-class electric storage hot water system

  • Product code EHFA400

  • Largest capacity model in the Rinnai Hotflo electric storage range

  • Ideal for larger families and high-demand homes

  • Rated capacity of 420L

  • Suitable for around 8 to 9 people in warm climate peak-period use

  • Suitable for 8 or more people in cool climate peak-period use

  • Suitable for 6 or more people in cool climate off-peak use

  • Vitreous enamel lined steel tank for durability

  • Inbuilt anode protection to help extend tank life

  • Dual handed connections for flexible installation

  • Pressure temperature relief valve included

  • Suitable for internal or external installation

  • Thermostatically controlled operation

  • Automatic safety temperature shut-off

  • Single and twin element configurations available

  • Lead free

  • Standard sizing for easier replacement and emergency changeovers

  • 3.6kW and 4.8kW heating element options

  • 240V 50Hz electrical supply

  • IPX4 ingress protection rating

  • Rp 3/4 water connections

  • 10-year cylinder warranty under Rinnai warranty terms

Quick Specs

Brand: Rinnai
Range: Hotflo Electric Storage
Product: Rinnai Hotflo 400L Electric Hot Water Storage
Product Code: EHFA400
System Type: Electric Storage Hot Water System
Rated Capacity: 420L
Common Product Class: 400L electric storage
Recommended Household Size: Larger families and very high-demand homes
Warm Climate Peak-Period Suitability: Around 8 to 9 people
Cool Climate Peak-Period Suitability: 8 or more people
Cool Climate Off-Peak Suitability: 6 or more people
Element Configuration: Single or twin element options available
Heating Elements Available: 3.6kW and 4.8kW
Electrical Supply: AC 240V 50Hz
Tank Lining: Vitreous enamel lined steel
Anode Protection: Inbuilt sacrificial anode
Installation Type: Internal or external installation
Water Connections: Rp 3/4
Connection Size: 20mm
Relief Valve Setting: 1000 kPa
Expansion Control Setting: 850 kPa
Maximum Water Supply Pressure With ECV: 680 kPa
Maximum Water Supply Pressure Without ECV: 800 kPa
Ingress Protection Rating: IPX4
Overall Height: 1840mm
Outlet Height: 1587mm
Inlet Height: 237mm
Lower Electrical Connection Height: 163mm
Tank Diameter: 675mm
Empty Weight: 96kg
Cylinder Warranty: 10 years subject to Rinnai warranty terms

Vitreous Enamel Lined Tank

The Rinnai Hotflo 400L uses a vitreous enamel lined steel tank designed to support long-term durability.

Vitreous enamel lining helps protect the steel tank surface from stored hot water conditions. The system also includes inbuilt anode protection, which helps protect the cylinder as part of the tank’s corrosion protection design.

Correct installation, water pressure control, water quality, valve setup and servicing conditions can all affect hot water system lifespan and warranty outcomes.

Inbuilt Anode Protection

The Rinnai Hotflo 400L Electric Water Heater includes inbuilt sacrificial anode protection to help extend the life of the hot water tank.

Anodes are designed to gradually wear over time as part of protecting the cylinder. This makes maintenance and water quality checks important for long-term performance, especially in large storage systems where water quality and operating conditions can have a major effect on service life.

Single and Twin Element Options

The Rinnai Hotflo 400L is available in single and twin element configurations.

A single element system is commonly used for standard electric storage replacement and may suit homes connected to suitable off-peak or standard tariff arrangements. A twin element system can provide faster recovery and additional hot water support during peak usage periods where the electrical setup and tariff arrangement suit it.

The correct option depends on household demand, selected variant, existing wiring, tariff connection and installation requirements.

Internal or External Installation

The Rinnai Hotflo 400L Electric Hot Water System is suitable for internal or external installation where the location is compliant and suitable.

This gives flexibility for homes replacing an existing indoor or outdoor electric storage system. Installation location still needs suitable access, drainage, ventilation, base support, valve setup, electrical connection and compliance with plumbing and electrical requirements.

Because this is a large-capacity tank, access, base condition and available working space should be checked carefully before ordering or installation.

Dual Handed Connections

The Rinnai Hotflo 400L includes dual handed connections to allow more flexibility during installation.

This can make replacement easier because the water connections can better suit different existing plumbing layouts. Dual handed connection options are useful in like-for-like replacement jobs where matching existing pipework can help reduce unnecessary plumbing changes.

Thermostatic Safety Control

The Rinnai Hotflo 400L is thermostatically controlled and includes automatic safety temperature shut-off.

This helps control stored water temperature and provides added protection as part of the system’s safety design.

420L Rated Storage Capacity

The 420L rated capacity makes this model the largest capacity option in the Rinnai Hotflo electric storage range.

This size is designed for homes where a smaller 250L or 315L system may not be enough. It can support larger families, shared households, rental properties and homes where hot water use is heavy across showers, laundry and kitchen demand.

For lower-demand homes, a 250L or 315L model may be more suitable. For households that want maximum stored hot water capacity, the Hotflo 400L is the stronger option.

Heating Recovery Guide

The recovery rate depends on the heating element size, incoming water temperature, thermostat setting, tank condition and power supply type.

As a general guide for a 50°C temperature rise:

  • 3.6kW element heats approximately 61.9 litres per hour

  • 4.8kW element heats approximately 82.5 litres per hour

A larger element can reheat water faster, but the correct option depends on electrical suitability, tariff setup, household demand and installation requirements.

Common Uses

The Rinnai Hotflo 400L Electric Hot Water System can be suitable for:

  • larger family homes

  • very high-demand households

  • shared households

  • larger townhouses

  • rental properties

  • investment properties

  • electric storage hot water replacement

  • internal or external hot water installations

  • homes needing more capacity than a 315L system

  • homes with heavy shower, laundry and kitchen hot water use

  • homes needing the largest Hotflo electric storage model

Frequently Asked Questions

Can I buy the Rinnai Hotflo 400L supply only?

Yes. You can buy the Rinnai Hotflo 400L as a supply-only product if you already have a licensed installer arranged.

Does Hot Water Outlet install electric hot water systems?

No. Hot Water Outlet does not directly provide installation services. Customers may request assistance arranging installation quotes after purchase in selected metro areas.

Can I get an installation quote after purchasing?

Yes. Customers in selected metro areas may request help arranging installation quotes through licensed local installers after purchasing the system.

Is delivery available Australia wide?

Metro delivery is available in selected service areas across Australia. Delivery availability may vary depending on location and product type.

What is the product code for the Rinnai Hotflo 400L?

The product code for the Rinnai Hotflo 400L electric storage water heater is EHFA400.

What is the rated capacity?

The Rinnai Hotflo 400L has a listed 420L rated capacity.

Why is it called 400L if the rated capacity is 420L?

It is commonly sold as the Rinnai Hotflo 400L electric storage model, while the listed rated capacity is 420L. This places it in the 400L-class large electric storage category.

How many people is the Rinnai Hotflo 400L suitable for?

The Rinnai Hotflo 400L is designed for larger families and high-demand homes. It is listed for around 8 to 9 people in warm climate peak-period use, 8 or more people in cool climate peak-period use, and 6 or more people in cool climate off-peak use. Actual suitability depends on shower length, usage pattern, tariff setup, climate and household demand.

Can the Rinnai Hotflo 400L be installed outside?

Yes. The Rinnai Hotflo 400L is suitable for internal or external installation where the location is compliant and suitable.

Is the Rinnai Hotflo 400L single element or twin element?

The Rinnai Hotflo 400L is available in single and twin element configurations.

What is the difference between single element and twin element?

A single element system has one heating element and is commonly used for standard electric storage replacement. A twin element system has two heating elements and can provide faster recovery and additional hot water support during peak demand periods where the electrical setup and tariff arrangement are suitable.

What element sizes are available?

The Rinnai Hotflo 400L lists 3.6kW and 4.8kW heating element options.

What is the tank lining?

The Rinnai Hotflo 400L uses a vitreous enamel lined steel tank.

Does the Rinnai Hotflo 400L have an anode?

Yes. The Rinnai Hotflo 400L includes inbuilt anode protection to help extend the life of the hot water tank.

What is the relief valve setting?

The Rinnai Hotflo 400L has a listed 1000 kPa relief valve setting.

What is the expansion control setting?

The Rinnai Hotflo 400L has a listed 850 kPa expansion control setting.

What is the maximum water supply pressure?

The Rinnai Hotflo 400L lists 680 kPa maximum water supply pressure with an expansion control valve and 800 kPa maximum water supply pressure without an expansion control valve.

What are the dimensions?

The Rinnai Hotflo 400L has an overall height of 1840mm and a tank diameter of 675mm.

How much does the Rinnai Hotflo 400L weigh?

The Rinnai Hotflo 400L has an empty weight of 96kg.

What is the IP rating?

The Rinnai Hotflo 400L has an IPX4 ingress protection rating.

What is the warranty on the Rinnai Hotflo 400L?

The Rinnai Hotflo 400L is listed with a 10-year cylinder warranty subject to Rinnai warranty terms and conditions.

Is the Rinnai Hotflo 400L good for replacing an old electric hot water system?

Yes. The Rinnai Hotflo 400L can be a strong replacement option for selected large electric storage hot water systems, provided the existing location, plumbing, electrical supply, water pressure, access and household hot water demand suit a 400L-class electric storage water heater.

What is the difference between the Rinnai Hotflo 315L and 400L?

The Rinnai Hotflo 400L provides more stored hot water than the 315L model and is better suited to very large families, shared households or homes with very high daily hot water use. The 315L model may suit larger households that still need strong capacity but do not require the largest Hotflo electric storage option.


* Requested element size may come delivered separately to system for electric systems - All units supplied with factory with 3.6kW

**Where a unit supplied is capable of supplying more than 50°C, a tempering valve must be installed on the property or purchased as part of a valve kit with your order.

Buying a new hot water system or hot water part should be simple. Hot Water Outlet helps you compare hot water systems, valves, thermostats, elements, pipework and fittings in one place, so you can choose the products that suit your home, budget and hot water needs without the back and forth.

Whether you already know exactly what you need or you are still comparing electric, gas, instant gas, gas storage or heat pump hot water options, Hot Water Outlet makes it easier to order with confidence.

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Shop hot water systems, valves, thermostats, elements, pipework and fittings online from one focused hot water store. Choose the system first, then add the parts and accessories needed for your setup.

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See your hot water system price upfront, then add common valves, fittings or accessories before placing your order. This makes it easier to plan your purchase and compare options before checkout.

Product Details That Actually Help

Key specs, sizing details, tank capacity, flow rate, gas type, energy source, dimensions, warranty information, product features and suitability notes are shown clearly, so you can compare hot water systems properly before you buy.

Valves and Accessories Available

Where relevant, you can add common hot water parts such as tempering valves, pressure relief valves, duo valves, non-return valves, thermostats, elements, pipework and fittings to help complete your order.

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Hot Water Outlet is focused on hot water systems and accessories for Australian homes, rentals, renovations and replacement projects. Browse trusted brands and compare practical options for common household hot water needs.

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Add your hot water unit and selected parts to cart in one order, instead of searching across multiple suppliers for systems, valves, fittings and accessories.

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Not sure which hot water system, size, energy type or accessory is right? Hot Water Outlet gives you a clearer way to compare electric hot water systems, heat pump hot water systems, gas storage hot water systems and instant gas hot water units before you order.

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Hot Water Outlet is built for customers who want a faster, clearer and more convenient way to buy hot water systems and hot water parts online.

Instead of guessing which product suits your home, searching multiple suppliers, or trying to match accessories separately, you can review the system, compare the specifications and add common hot water parts before checkout.

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It is a simpler way to buy the hot water products and parts that matter most.

Important Note

Product suitability can vary by property, existing services, energy source, gas type, available space, connection points, pressure requirements and local compliance requirements. Always check product specifications carefully and confirm the selected hot water system, valves, fittings and accessories are suitable for your property before ordering.

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Express Delivery: 1–4 business days

90% of products are delivered the next business day where stock, postcode eligibility and freight availability allow.

Delivery timeframes are estimates and may vary by product, stock location, delivery postcode, carrier availability and order timing. Wet weather, storms, flooding or unsafe site access may delay delivery and are additional to any advertised or guaranteed freight timeframes.

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