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Rheem 20 Natural Gas Hot Water System

Was $1,149.00, Now $929.00
Hot Water Outlet
Add the parts you need

Choose quote help, valves, copper, fittings, support bases and sundries with this order.

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Add this service to your order and Hot Water Outlet can help request quotes from up to 4 reputable licensed installers in your area. Installation is quoted and arranged separately with the installer.
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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: 1-7 people
  • Make: Rheem
  • Model: 876620
  • Volume: 20L
  • Maximum Warranty: 10 years
  • Height: 580 mm
  • Width: 355 mm
  • Made In: Japan
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
Check your postcode

Rheem 20L Natural Gas Continuous Flow Hot Water System 50°C

The Rheem 20L Natural Gas Continuous Flow Hot Water System 50°C is available online from Hot Water Outlet as a supply-only natural gas hot water unit with metro delivery available in selected areas Australia wide.

Customers can purchase the Rheem 20L Natural Gas continuous flow water heater as a supply-only gas hot water system and request assistance arranging installation quotes after purchase through licensed local installers in selected metro regions.

The Rheem 20L Natural Gas 50°C continuous flow water heater is a compact, medium-capacity gas hot water system designed for homes, townhouses, apartments and replacement jobs where a storage tank is not ideal. With 20 L/min continuous hot water delivery at a 25°C rise, a 6-star energy rating, 50°C factory temperature-limited output and compact wall-mounted design, it is a strong option for customers wanting reliable natural gas hot water for up to 2 bathrooms where site conditions are suitable.

About the Rheem 20L Natural Gas Continuous Flow Water Heater

The Rheem 20L Natural Gas Continuous Flow Water Heater is part of Rheem’s compact gas continuous flow range. It heats water only when hot water is needed rather than storing a full tank of heated water.

This makes it a practical option for homes where outdoor space is limited, where a wall-mounted gas unit is preferred, or where the existing setup already suits an external natural gas continuous flow hot water replacement.

The 20L model is designed for around 2 bathrooms depending on climate, water pressure, pipe sizing, fixture flow rates, outlet demand and household usage. It provides more flow capacity than the smaller 16L model, making it better suited to homes with higher hot water demand while still keeping a compact wall-mounted footprint.

This is the natural gas version. Natural gas and LPG models are not interchangeable, so the correct gas type must be selected before ordering or installation.

Buy Rheem 20L Natural Gas Supply Only

Order the Rheem 20L Natural Gas Continuous Flow Water Heater online from Hot Water Outlet with metro delivery available in selected areas across Australia.

This option is ideal for customers who already have a licensed gas fitter or plumber 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, gas fitting work, electrical work, plumbing alterations, drainage changes, compliance upgrades and additional site requirements are not included unless separately quoted.

Supply-only is ideal for customers searching for:

  • Rheem 20L natural gas price

  • Rheem 20L natural gas continuous flow hot water system

  • Rheem 876A20 natural gas hot water system

  • Rheem 876A20NF gas water heater

  • Rheem natural gas instantaneous hot water system

  • 20L natural gas continuous flow hot water supply only

  • Rheem Metro 20 natural gas hot water system

Installation Quotes Available After Purchase

Hot Water Outlet does not directly provide installation services.

After purchasing the Rheem 20L Natural Gas Continuous Flow Hot Water System, customers in selected metro areas may request assistance arranging installation quotes through licensed local plumbers and gas fitters.

Installation quote availability depends on:

  • service location

  • installer availability

  • existing system type

  • natural gas suitability

  • gas pipe sizing

  • water pressure

  • plumbing suitability

  • electrical requirements

  • compliance requirements

Additional installation costs may apply for:

  • valve upgrades

  • gas pipe upgrades

  • water pressure control

  • drainage changes

  • pipework changes

  • difficult access

  • old system removal

  • disposal

  • compliance upgrades

Rheem 20L Natural Gas Delivery Brisbane

Hot Water Outlet offers metro delivery for the Rheem 20L Natural Gas Continuous Flow Hot Water System in selected Brisbane areas.

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

Rheem 20L Natural Gas Delivery Gold Coast

Hot Water Outlet offers metro delivery for the Rheem 20L Natural Gas Continuous Flow 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.

Rheem 20L Natural Gas Delivery Sydney

Hot Water Outlet offers metro delivery for the Rheem 20L Natural Gas Continuous Flow Hot Water System in selected Sydney metro areas.

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

Rheem 20L Natural Gas Delivery Melbourne

Hot Water Outlet offers metro delivery for the Rheem 20L Natural Gas Continuous Flow Hot Water System in selected Melbourne metro areas.

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

Is the Rheem 20L Natural Gas Right for Your Home?

The Rheem 20L Natural Gas Continuous Flow Hot Water System may be suitable if you are replacing an existing natural gas water heater and want a compact external unit with stronger flow than a smaller 12L or 16L continuous flow model.

It is commonly suited to:

  • small and medium homes

  • townhouses

  • apartments

  • granny flats

  • rental properties

  • homes with around 2 bathrooms

  • homes already connected to natural gas

Suitability depends on:

  • gas type

  • natural gas supply

  • gas pipe sizing

  • water pressure

  • number of outlets

  • household hot water demand

  • pipework

  • wall location

  • clearances

  • compliance requirements

This system may suit you if:

  • you are replacing an existing external natural gas hot water system

  • your property uses natural gas, not LPG

  • you want a 20 L/min continuous flow gas water heater

  • you want a 50°C temperature-limited model

  • your home has up to around 2 bathrooms depending on usage

  • your external wall location has suitable access and clearances

  • your water pressure and natural gas supply are suitable

  • you prefer supply-only purchase flexibility

Additional installation work may be required depending on:

  • existing plumbing condition

  • gas pipe sizing

  • water pressure

  • electrical requirements

  • access limitations

  • compliance upgrades

  • installation location requirements

Key Features of the Rheem 20L Natural Gas 50°C

  • Natural gas continuous flow hot water system

  • 50°C factory temperature-limited model

  • 20 L/min continuous hot water delivery at a 25°C temperature rise

  • Suitable for around 2 bathrooms depending on conditions

  • Compact wall-mounted design

  • Outdoor installation only

  • 6-star energy rating

  • Flamesafe® overheat protection

  • Rheem Q Factor™ for improved hot water temperature stability

  • Smart electronic control

  • Digital OK monitor for temperature display and diagnostics

  • Low minimum operating flow rate of 1.5 L/min

  • Remote temperature controller options available

  • Natural gas and LPG / propane variants available

  • 519mm high

  • 355mm wide

  • 188mm deep

  • Approximate empty weight of 16kg

  • 12-year heat exchanger parts warranty under Rheem warranty terms

  • 3-year heat exchanger labour warranty under Rheem warranty terms

  • 3-year parts and labour warranty on other domestic components under Rheem warranty terms

Quick Specs

Brand: Rheem
Product: Rheem 20L Gas Continuous Flow Water Heater 50°C
Model Family: 876A20
Likely Natural Gas Model Code: 876A20NF
Gas Variant: Natural Gas
System Type: Gas Continuous Flow Hot Water System
Installation Type: Outdoor installation only
Temperature Setting: 50°C factory temperature-limited model
Flow Rate: 20 L/min at 25°C temperature rise
Bathroom Suitability: Around 2 bathrooms depending on climate and demand
Energy Rating: 6 star
Minimum Operating Flow Rate: 1.5 L/min
Nominal Gas Consumption: 157 MJ/hr
Maximum Water Supply Pressure: 1000 kPa
Minimum Water Supply Pressure: 120 kPa
Cold Water Connection: R 3/4
Hot Water Connection: R 3/4
Gas Connection: R 3/4
Height: 519mm
Width: 355mm
Depth: 188mm
Approximate Empty Weight: 16kg
Temperature Controller Options: Kitchen, Bathroom 1 and Bathroom 2 controller options available
Accessory Options: Pipe cover, recess box, security cage and wall mount security kit available
Heat Exchanger Warranty: 12 years parts and 3 years labour subject to Rheem warranty terms
Other Domestic Components Warranty: 3 years parts and labour subject to Rheem warranty terms

Compact Continuous Flow Design

The Rheem 20L Natural Gas continuous flow water heater is designed to save space compared with a traditional gas storage hot water system.

Because it heats water on demand, it does not require a large storage cylinder. The compact body can be mounted externally on a suitable wall, making it useful for homes with limited outdoor space, narrow side access, townhouses, units and medium-capacity replacement locations.

50°C Temperature-Limited Output

This model is the 50°C factory temperature-limited version.

A 50°C model can be a practical option for domestic hot water installations where safer outlet temperature control is important.

Some applications may still require additional tempering or installation controls depending on the property, plumbing layout, fixtures and compliance requirements. Suitability should be confirmed before installation.

Natural Gas Hot Water

This product is the natural gas version of the Rheem 20L continuous flow water heater.

It is intended for homes connected to natural gas. It is not the same as the LPG version, and the two gas types cannot be swapped without selecting the correct product and completing suitable licensed gas work.

Customers should confirm their gas type before ordering.

Rheem Q Factor™ and Flamesafe® Protection

The Rheem 20L Natural Gas includes Rheem Q Factor™ technology designed to help deliver steady hot water temperature and reduce the fluctuations that can occur with some continuous flow systems when hot water demand changes.

It also includes Flamesafe® overheat protection, which is designed to shut down the water heater before overheating can occur.

Common Uses

The Rheem 20L Natural Gas 50°C Continuous Flow Hot Water System can be suitable for:

  • natural gas hot water replacement

  • external continuous flow hot water applications

  • homes connected to natural gas

  • apartments and townhouses

  • granny flats

  • small to medium homes

  • rental properties

  • compact wall-mounted replacement locations

  • homes with around 2 bathrooms depending on demand

Frequently Asked Questions

Can I buy the Rheem 20L Natural Gas supply only?

Yes. The Rheem 20L Natural Gas can be purchased online as a supply-only product with metro delivery available in selected areas.

Does Hot Water Outlet install gas 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 and gas fitters 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.

Is this model natural gas or LPG?

This page is for the natural gas version of the Rheem 20L 50°C continuous flow water heater. Natural gas and LPG units are not interchangeable, so the correct gas type must be selected before ordering or installation.

Can this Rheem gas hot water system be installed indoors?

No. This is an outdoor gas hot water system and is not designed for internal installation. Gas hot water units must be installed in accordance with location, clearance, ventilation and compliance requirements.

What is the flow rate of the Rheem 20L Natural Gas?

The Rheem 20L Natural Gas continuous flow water heater delivers 20 L/min at a 25°C temperature rise.

How many bathrooms is the Rheem 20L suitable for?

Rheem lists the 20L model as suitable for around 2 bathrooms depending on climate, water pressure, pipe sizing, appliance flow rates and household usage.

What is the minimum water pressure required?

The Rheem 20L model is listed with a minimum water supply pressure of 120 kPa.

What is the maximum water supply pressure?

The Rheem 20L model is listed with a maximum water supply pressure of 1000 kPa.

What is the minimum operating flow rate?

The Rheem 20L model has a listed minimum operating flow rate of 1.5 L/min.

What is the gas consumption?

The Rheem 20L model is listed with a nominal gas consumption of 157 MJ/hr.

What are the dimensions?

The Rheem 20L continuous flow unit is approximately 519mm high, 355mm wide and 188mm deep.

Does the Rheem 20L Natural Gas have temperature controller options?

Yes. Rheem lists optional kitchen and bathroom temperature controllers for the 20L continuous flow range.

What is the warranty on the Rheem 20L Natural Gas?

Rheem lists the 20L continuous flow range with a 12-year parts and 3-year labour warranty on the heat exchanger plus 3-year parts and labour warranty on other components subject to Rheem warranty terms.

Is the Rheem 20L Natural Gas good for replacing an old natural gas hot water system?

Yes. The Rheem 20L Natural Gas can be a practical replacement where the existing system is natural gas, the installation location is external, and the gas supply, water pressure, pipework and compliance requirements are suitable.

What is the difference between the Rheem 16L and 20L continuous flow models?

The Rheem 20L model provides a higher flow rate than the 16L model. The 16L model is commonly suited to around 1 to 1.5 bathrooms, while the 20L model is commonly suited to around 2 bathrooms depending on site conditions and household demand.

What is the difference between the 50°C and 60°C Rheem 20L models?

The 50°C model is factory temperature-limited for domestic hot water applications. The 60°C model can deliver higher outlet temperature and generally requires tempering to meet bathroom outlet temperature requirements. The right model depends on the property, plumbing layout and compliance requirements.

 

    * 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.

    Why Customers Choose Hot Water Outlet

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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.

    Designed To Make Your Decision Easier

    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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    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.

    Standard Delivery: 2–8 business days

    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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