Gas Storage to Heat Pump Hot Water: Is It Worth Upgrading?
Gas Storage to Heat Pump Hot Water: Is It Worth Switching?
For many homes, yes. Gas-storage properties are often particularly good heat-pump conversion candidates because the home already has a full-sized outdoor hot-water cylinder position.
Both systems store hot water in a tank. The major change is the heat source: gas storage burns natural gas or LPG to keep a stored reserve hot, while a heat pump uses electricity to move heat from the surrounding air into the water. If the existing tank site has suitable airflow, drainage, electrical access and noise separation, the physical conversion can be much more straightforward than moving from a wall-mounted continuous-flow system.
Should You Switch From Gas Storage?
You already have a storage-tank location. The big questions are the fuel you use now, whether that site suits heat-pump airflow and noise, and whether solar PV strengthens the case further.
1What gas does the current storage system use?
2What is the current tank position like?
3Do you have rooftop solar PV?
Guide only. Tank dimensions, airflow, compressor noise, condensate drainage, electrical supply, gas isolation, plumbing, household demand and local installation requirements must be checked for the selected model.
Can You Replace Gas Storage With a Heat Pump?
Yes. Gas storage can be replaced with a suitably sized heat-pump hot-water system where the site has enough space, airflow, drainage, suitable electrical supply and acceptable noise separation. Because both technologies use a storage cylinder, the existing hot-water position can often provide a very useful starting point.
Why Gas Storage Is Such a Strong Heat-Pump Upgrade Candidate
Gas storage already gives the property the infrastructure pattern a heat pump wants: a ground-level tank location, stored-hot-water plumbing and usually relief drainage nearby. The main additions are suitable electrical supply, airflow and condensate management.
Tank Space Already Exists
The property already allocates ground space to a full-sized hot-water cylinder, which can make a heat-pump upgrade far easier to accommodate.
Water Services Are Already There
Hot and cold water services are already located at the storage site, although connection points may need alteration for the new unit.
Gas Storage Has Standby Losses
Gas storage continually maintains a heated tank and cannot insulate the burner area in the same way as a fully insulated electric storage cylinder, which is one reason government guidance describes gas storage as particularly inefficient.
Solar PV Becomes Useful for Hot Water
Rooftop PV cannot fuel a gas burner. A heat pump can be scheduled into daylight hours and use household-generated electricity instead.
STCs May Reduce the Upgrade Cost
Eligible air-source heat-pump models can create Small-scale Technology Certificates when the exact model and installation satisfy current scheme requirements.
Opportunity to Reduce Gas Reliance
If hot water is a major gas load—or the last one—switching it to heat pump can materially change the role gas plays in the home.
Gas Storage vs Heat Pump: Compare the Complete Pathway
Do not compare only the appliance price. A like-for-like gas-storage replacement can be cheaper upfront, while a heat pump can require electrical work but may reduce ongoing energy use and qualify for certificate or state incentive pathways.
A familiar like-for-like pathway where the gas service, tank location and household demand already suit the existing setup.
The live gas collection includes both storage and instant gas systems, so compare the relevant storage models rather than relying on the lowest collection price alone.
Keeps a ground-level storage format while moving normal hot-water heating away from gas and toward a much more efficient electric technology.
Current Installed Today heat-pump collection starting price. Product, order type, installation scope and incentive eligibility can change the final cost.
Gas Storage vs Heat Pump Hot Water
| Consideration | Gas Storage | Heat Pump |
|---|---|---|
| Main heat source | Natural gas or LPG burner | Heat from surrounding air + electricity |
| Hot-water format | Stored hot water | Stored hot water |
| Existing tank site | Direct fit advantage Existing site already established | Often useful Can often use the same general site if airflow, noise and clearances suit |
| Energy efficiency | Gas burner plus storage heat losses | Strong advantage Uses a refrigeration cycle to move heat rather than relying on combustion |
| Solar PV compatibility | PV cannot fuel the gas burner | Highly recommended Can be scheduled to use daytime household solar generation |
| Gas required | Yes for normal heating | No gas required for normal operation |
| Electrical requirement | Depends on the gas model and controls | Requires a suitable electrical supply, isolation and protection |
| Noise | Burner operation | Compressor and fan operate while heating |
| STCs | No heat-pump / solar STC pathway | Eligible listed systems may qualify |
| Our preference if both suit | Mainly for lower conversion cost, familiar gas setup or a genuine heat-pump site constraint | Recommended long-term upgrade in most suitable homes |
The Existing Gas-Storage Tank Position Is a Major Advantage
The old gas cylinder site can often provide much of the physical foundation for the new system. It still needs to suit the selected heat pump, but you are usually starting with far more useful infrastructure than an instant-gas conversion.
Existing Base
The current foundation may be reusable if its dimensions, level, condition and loaded capacity suit the new heat pump.
Hot & Cold Plumbing
Water services are already present, although the heat pump's connection positions may require pipework changes.
Relief Drainage
Existing relief drainage can be useful, subject to current requirements and the selected unit's discharge arrangement.
Condensate
The heat-pump section can create condensate, so the new system may need an additional sensible drainage path.
Airflow
This is the biggest new site requirement. A location that suited a gas tank still needs enough free air and manufacturer-specified clearances for the heat pump.
Service Access
Allow access to the compressor, fan, controls and water connections so the new system remains practical to maintain.
What Happens to the Existing Gas Connection?
The branch serving the old gas-storage unit needs to be safely isolated or altered. Whether the home keeps its broader gas supply depends on what else still uses gas.
Keep the Property Gas Supply
Cooktops, fireplaces or other gas appliances can continue using the existing service. Only the redundant hot-water branch needs to be dealt with as part of the conversion.
Consider a Broader Gas Exit Separately
If no other appliance needs gas, changing the hot-water system may create an opportunity to consider closing or abolishing the gas service and avoiding future gas-supply charges. That broader step is separate from simply removing the old water heater.
Does Gas Storage Already Have the Electrical Supply a Heat Pump Needs?
Do not assume so. Some gas-storage systems use electricity for ignition, controls or other components, while others have very different electrical requirements from a heat pump. The new system still needs a supply, isolation and protective arrangement that matches the selected model.
Power May Already Be Nearby
If the existing gas unit has powered controls, there may already be electricity at the hot-water site, which can be useful.
Load Can Be Different
A heat pump has a compressor, fan, controls and sometimes an electric backup element, so its electrical requirements are not the same as a small gas-appliance control load.
New Circuit Work May Be Required
Depending on the selected model and existing installation, electrical extension, conversion, isolation or a new circuit may form part of the job.
Already Have Solar PV? We Would Strongly Favour the Heat Pump
This is where the technology change becomes especially compelling. Rooftop PV cannot offset the gas burned by a storage water heater, while a heat pump can be scheduled to run during strong daytime solar production and store that energy as hot water.
Gas Storage
Solar PV does not fuel the burner. The hot-water load remains tied to natural gas or LPG.
Heat Pump + Grid Electricity
Even without solar, a heat pump is a highly efficient electric hot-water technology because it moves ambient heat into the tank.
Heat Pump + Solar PV
Daytime scheduling lets the home use its own generation to power a comparatively low electrical hot-water load and store the result for later use.
If your gas-storage tank is already outside, the site suits a heat pump and the home has rooftop solar, we would normally consider heat pump the standout replacement pathway rather than another gas-storage system.
Do You Need the Same Tank Size as Your Old Gas Storage System?
Not automatically. Gas storage and heat pumps both store water, but their recovery characteristics are different. Select the heat pump around household demand, stored volume, recovery rate, operating schedule and climate rather than matching litres alone.
Household Size
More occupants increase total daily hot-water demand and the reserve needed through peak periods.
Peak Shower Demand
Back-to-back showers, baths and multiple bathrooms matter more than simply comparing old and new tank labels.
Gas Recovery vs Heat-Pump Recovery
Gas burners can recover stored water differently from a heat-pump compressor, so a smaller old tank does not automatically justify the same heat-pump capacity.
Solar Operating Window
If the heat pump will mainly run during daylight, enough storage is needed to carry the household through the non-heating periods.
Backup Element Strategy
Some heat pumps use an electric booster for high demand or low ambient conditions. How often it runs changes both recovery and energy use.
Climate
Ambient temperature affects heat-pump performance, so select a model suitable for the installation climate and expected winter conditions.
When We Would Highly Recommend Heat Pump Over Another Gas-Storage Unit
Gas-storage homes already solve the hardest spatial problem. If several of these conditions apply, heat pump becomes our clear first comparison.
The Existing Tank Is Outside
A practical open-air cylinder position often gives the new heat pump the airflow and physical space it needs.
You Already Have Solar PV
This allows the home to turn daytime solar electricity into stored hot water instead of continuing to burn gas.
The Gas Unit Is Already Due for Replacement
The replacement event is the natural point to change technology because the old system is already being removed and replaced.
Hot Water Is the Last Gas Appliance
The conversion can become part of a broader move away from the gas supply, subject to what else the property needs.
You Use LPG
Moving everyday water heating away from bottled or bulk LPG can simplify fuel dependence and makes heat pump especially worth comparing.
You Expect to Stay in the Home
A longer ownership horizon gives the lower ongoing energy requirement more time to offset higher upfront conversion costs.
When Staying With Gas Storage Can Still Make Sense
Heat pump is our preferred upgrade where practical, but gas storage can still be the sensible choice when a real site or budget constraint outweighs the efficiency advantage.
The Tank Area Has Poor Airflow
If the only available cylinder site is genuinely enclosed and there is no practical relocation option, a heat pump may not suit that position.
Noise Cannot Be Sensibly Managed
A location directly beside sensitive bedrooms or a close neighbour may make another gas-storage unit simpler if no quieter model or alternate position solves the issue.
Lowest Upfront Cost Is the Priority
A like-for-like gas replacement can avoid some electrical conversion work and may cost less initially, particularly where the gas infrastructure remains in good condition.
Can a Gas-Storage-to-Heat-Pump Upgrade Qualify for STCs?
Eligible air-source heat-pump water heaters can create federal Small-scale Technology Certificates when the exact model is on the current Clean Energy Regulator register and the completed installation satisfies the scheme requirements.
Eligible Heat Pumps Can Receive STCs
Certificate quantity depends on the approved model, installation date and geographic zone. The system must be installed in the registered configuration.
Additional Support Can Vary
Some jurisdictions have extra heat-pump discounts, rebates or efficiency programs. Eligibility can depend on the existing gas system, property, postcode, household and approved provider.
Confirm the Claim Pathway Before Installation
Buying an eligible model does not complete an STC or state claim by itself. Confirm the installer, registered agent or accredited-provider requirements before work starts.
Supply Only vs Supplied & Installed
Installed Today supports supply-only ordering across suitable Australian metro delivery areas and supplied-and-installed options on eligible products in Brisbane and Gold Coast service areas.
Arrange the Licensed Trades Yourself
This conversion can involve plumbing, gas and electrical work. Confirm the complete scope, the selected model's requirements and any incentive claim pathway with the relevant licensed installers before installation.
- Product price is for the selected product unless shown otherwise.
- Gas isolation, electrical work, valves, disposal and pipework changes are not automatically included.
- Confirm STC or state-program paperwork before work starts where required.
Available on Eligible Products & Locations
Where an installed option is offered, select the system and work through the installation choices shown for that product. Final suitability depends on site access, existing services and required plumbing, gas and electrical work.
- Check the exact installation inclusions shown with the product.
- Electrical conversion or circuit work may be a separate option.
- Gas and site changes can affect the final installed cost.
How a Gas-Storage-to-Heat-Pump Conversion Usually Works
Assess the Existing Tank Site
Check base, space, airflow, noise, drainage, access and the existing hot and cold services.
Size the Heat Pump
Match stored volume and recovery to the household instead of copying the old gas tank capacity automatically.
Confirm Gas & Electrical Work
Plan safe isolation of the old gas branch and confirm the electrical supply, isolation and protection required by the selected heat pump.
Install & Commission
Remove the gas tank, complete plumbing and electrical work, set the controls and complete any eligible certificate pathway.
Gas Storage to Heat Pump Hot Water FAQs
Can I replace gas storage hot water with a heat pump?
Yes. Gas-storage homes can be particularly good conversion candidates because a full-sized hot-water cylinder position already exists. The site still needs suitable airflow, noise separation, drainage, electrical supply and service clearances for the selected heat pump.
Is a heat pump better than gas storage hot water?
Where the site is suitable, we generally favour heat pump as the long-term upgrade. Gas storage has ongoing storage and burner-related losses, while heat pumps use a refrigeration cycle to move heat from the air into the water and can also use rooftop solar electricity.
Can the heat pump use the same spot as my gas-storage tank?
Often the same general location can be useful, especially when the gas tank is already outdoors in an open area. The base, dimensions, airflow, compressor noise, condensate drainage, service access and electrical supply still need to suit the new system.
Is heat pump worth it if I already have solar panels?
Usually this is one of the strongest reasons to switch. Rooftop PV cannot supply the gas burner, while a heat pump can be scheduled during the day to use household-generated electricity and store the energy as hot water.
What happens to the old gas connection?
The branch serving the old gas water heater needs to be safely isolated or altered. If other appliances still use gas, the broader supply can remain. If hot water was the last gas appliance, closing or abolishing the property gas supply can be considered separately.
Does a gas-storage site already have enough electricity for a heat pump?
Not necessarily. Any existing electrical supply for a gas appliance may only support ignition or controls. The heat pump's circuit, isolation and protective requirements must be checked against the exact selected model.
Should I choose the same litres as my old gas tank?
Not automatically. Gas storage and heat pumps have different recovery characteristics. Heat-pump sizing should consider household size, peak shower demand, tank volume, recovery rate, climate and operating schedule.
Can I get STCs when replacing gas storage with a heat pump?
Eligible air-source heat-pump models can create Small-scale Technology Certificates when the exact model is on the current Clean Energy Regulator register and the completed installation satisfies the scheme requirements.
When is another gas-storage system still the better fit?
Gas storage can remain practical where the existing site cannot provide suitable heat-pump airflow, compressor noise cannot be managed, electrical conversion work is disproportionate or lowest upfront replacement cost is the overriding priority. If the site is otherwise suitable, we would normally favour heat pump.
Is LPG gas storage worth changing to heat pump?
It is usually worth a strong comparison. A heat pump removes bottled or bulk LPG from normal hot-water heating and can use household electricity or rooftop solar instead, while the existing storage-tank footprint can help with the physical conversion.
Can I buy the heat pump supply only?
Supply-only ordering is available on suitable products and delivery areas. Because the conversion can involve plumbing, gas and electrical work, confirm the full licensed-trade scope and any STC or state-incentive requirements before installation.
Replacing Gas Storage? Compare Heat Pump Before You Buy Another Gas Tank
You already have the biggest physical advantage: a property designed around a storage cylinder. If that position has suitable airflow, noise separation, drainage and electrical access, heat pump is the pathway we would compare first—especially with rooftop solar or where the home is reducing its reliance on gas.
