Gas hot water systems on the Mornington Peninsula
Updated October 2026
Gas hot water has long been a favourite in Peninsula homes that cook with gas. It heats fast, recovers quickly after a run of showers, and running costs have historically sat well below full-rate electric storage. Mornington Hot Water connects you with licensed plumbers and gasfitters across the Mornington Peninsula who install, replace and repair gas hot water systems.
We are a referral service. The licensed hot water plumbers we work with are licensed or registered with the Victorian Building Authority, and gas connection work is done by plumbers holding the relevant gasfitting endorsement, as Victorian law requires.
How gas hot water works
There are two types. Gas storage keeps a tank of water hot around the clock, with a burner underneath that fires when the temperature drops. Gas continuous flow (also called instantaneous) has no tank. It heats water on demand as it passes through, so you never run out. Continuous flow has largely taken over for new installs, but storage still suits homes that want the simplest like-for-like swap. Continuous flow has its own page.
Lifespan and running costs
Gas storage tanks typically last 8 to 12 years. Continuous flow units often go longer, 15 to 20 years with occasional servicing, because there is no tank to corrode. Natural gas heats water cheaply per litre, though supply charges have risen and the gap over electric alternatives has narrowed. If your household already uses gas for cooking or heating, gas hot water usually still stacks up. If hot water would be the only gas appliance, compare a heat pump before committing to a new connection. Victoria has also been steering new homes away from gas connections, so a new build is a different conversation from a replacement in an existing house.
As a typical range, gas hot water systems run about $1,200 to $3,500 installed. Your quote depends on unit size, flue requirements and the state of the existing gas line.
Mains gas or LPG: it varies by address
Natural gas reaches much of the bay-side strip and the larger townships, from Mount Eliza and Mornington through Dromana and Rosebud, and across the Western Port towns. Availability genuinely varies by address, and large parts of the hinterland at Red Hill, Main Ridge, Merricks, Moorooduc and Tuerong, along with the southern coastal settlements, have no mains connection at all. Those properties run LPG bottles, which work fine but cost more per litre of hot water and need refilling. For a holiday house, running out of gas mid-stay is a real consideration. The plumber confirms what your street and meter can support before quoting, so you are never sold a system you cannot run.
Repair or replace
If the fault is a thermocouple, pilot assembly, igniter or valve, repair is normally the right call and costs a fraction of replacement. If a storage tank is leaking from the cylinder, it has corroded through and must be replaced. If your gas storage tank is past ten years old, ask for a replacement price alongside any big repair, and consider whether continuous flow makes more sense than another tank.
Local conditions to factor in
Externally mounted gas units close to the water, along the bay from Mount Martha to Portsea and on the exposed southern coast, wear faster in salt air, so placement and corrosion protection matter. In Mornington and Rosebud townhouses and units, flueing rules and owners corporation approval usually dictate what can go in, and many are limited to a like-for-like swap. Freestanding houses have far more flexibility on unit position and type. On a holiday house, a continuous flow unit avoids the problem of a tank keeping water hot for an empty building.
Licensing: non-negotiable in Victoria
Any work on a gas appliance or gas line in Victoria must be done by a plumber holding the relevant gasfitting endorsement, and the plumbing side by a licensed or registered plumber. Unlicensed gas work is illegal and dangerous. Every tradesperson we refer holds the licences the job requires, and you should receive a compliance certificate for plumbing work valued over $750.
Get a fast quote for gas hot water from a licensed local plumber and gasfitter.
Frequently asked questions
How much does a gas hot water system cost installed?
Typical pricing runs about $1,200 to $3,500 installed, covering storage and continuous flow in common household sizes. Flue changes, gas line upgrades or relocating the unit add to the price. The plumber quotes the full installed figure before work starts.
Is gas hot water cheaper to run than electric?
Cheaper than a standard electric storage tank on full-rate power, yes. Against a heat pump, the comparison is closer and depends on your gas supply charges and electricity rates. On LPG the heat pump usually wins. If you are replacing a system anyway, get both options quoted.
My street has no gas main. What are my options?
LPG bottles can run a gas system, but bottle costs make running costs higher than mains gas. Most households in that position compare LPG continuous flow against a heat pump or electric storage. The plumber can price both paths.
Can a gas hot water system go in a townhouse or unit?
Yes, but it must be properly flued to the outside, and owners corporation approval is usually needed. Many installs are restricted to replacing the existing unit in the same position. A licensed gasfitting plumber confirms what is compliant for your building.