Cold shower this morning? Unit dripping in the side passage? Error code on the controller that won't reset? Or just an old gas storage unit you know is on borrowed time? Prime Plumbing & Gasfitting quotes hot water replacement across Melbourne — like-for-like swaps, upgrades to continuous-flow, and heat pump replacements with rebate paperwork sorted. We diagnose first, replace where it's the right call, and have most replacements running again the same day.
Hot water replacement in Victoria covers two regulated trades. The plumbing side covers water connections, tempering valves, pressure-relief valve discharge lines, and the unit's physical install — all required to comply with AS/NZS 3500 and to be carried out by a BPC-licensed plumber. The gas side (for gas storage and continuous-flow units) covers the regulator, line sizing, flue clearances, pressure testing and Compliance Certificate lodgement with Energy Safe Victoria — a Type A Gasfitter endorsement.
Heat pump replacements add electrical work, which we coordinate with a licensed electrician where new circuit work is required. The replacement isn't "plug and play" even when it looks physically straightforward — getting it Compliance-Certificated correctly is what protects you if a future leak triggers an insurance claim.
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Water connections, hot-and-cold lines, tempering valves and pressure-relief valve discharge lines all comply with AS/NZS 3500. Tempering valves at the unit limit hot water temperature at outlets to 50°C as required by Victorian regulation.
For gas units (storage and continuous-flow), the gas connection, regulator, flue, clearances and pressure testing all comply with AS/NZS 5601. Gas line sizing matters on continuous-flow replacements where the new unit's BTU draw exceeds the existing unit's design capacity.
Plumbing replacement work above the threshold gets a BPC Compliance Certificate; gas work gets a Certificate of Compliance lodged with Energy Safe Victoria the same day. PDFs emailed to you with the invoice. Useful at sale, for insurance, and on the rare occasion an issue needs warranty follow-up.
On the booking call we ask the unit's make, model and approximate age, and what's happening — no hot water, leaking, error code, or just past expected service life. If we can scope the replacement from the call (most like-for-like swaps), we can quote the replacement price and book the install in one conversation.
On arrival we confirm the existing unit's condition, gas/water/electrical connections, and any access constraints (side passage clearances, roof cavity space for heat pumps). If a repair is genuinely cheaper long-term — for example a unit under 8 years old with a failed thermocouple — we'll tell you. Most callouts on units past 12+ years end up replaced.
Quotes come with at least two options where it's sensible: the cheapest like-for-like swap, plus a relevant upgrade (continuous-flow if you're tired of running out, or heat pump if rebates make it worthwhile). Each option has the install price, expected running cost, and any rebate that applies — so you can make the decision with the actual numbers.
Drain-down the old unit, disconnect water, gas (or electrical for heat pumps), remove and dispose of the old unit, install the new unit, reconnect, pressure test, commission, and leak-check. Most like-for-like replacements run for 2-4 hours on-site; heat pumps with new electrical work can be a half-day. We aim to leave you with hot water before we leave.
Plumbing Compliance Certificate lodged with the Plumbing Industry Commission the same day. Gas Certificate of Compliance lodged with Energy Safe Victoria the same day. For heat pump installs, we handle the Victorian Energy Upgrades (VEU) rebate paperwork — eligibility varies by household and unit so we confirm before quoting. PDFs of all certificates emailed to you with the invoice.
The information you collect before the replacement visit determines how accurate the quote is and whether we can complete the install in a single visit. Five minutes spent on this saves a return trip.
The data plate on the existing unit (usually a sticker on the side or near the gas connection) shows make, model number and serial number. The serial number includes the year of manufacture. Photograph the data plate and send it through with your enquiry — it tells us the right replacement and any specific connections we need to bring.
Storage tanks have a litre capacity (135L, 170L, 250L, 315L are common Australian sizes). Continuous-flow units have a flow rate (16L, 20L, 26L per minute). Knowing what you've got helps us recommend a matching replacement — and lets you decide whether to upsize if your household has grown.
If the unit is in a side passage, roof cavity, garage corner or laundry, clear pot plants, garden tools, washing baskets and storage so we can manoeuvre the new unit in and the old unit out. Heat pump replacements need clearance for the larger external unit.
If you've had recent plumbing or gas work near the hot water unit, tell us. Some failures shortly after adjacent work are connected — and the right diagnosis depends on knowing the history.
Like-for-like gas storage or electric storage replacements typically take 2-4 hours on-site. Continuous-flow gas replacements are similar. Heat pump replacements with new electrical work can take a half-day. Most replacements complete in a single visit and you have hot water before we leave.
Like-for-like gas storage replacement is usually the cheapest upfront. Electric storage is comparable. Continuous-flow gas costs more upfront but uses less standing-loss energy. Heat pump is the highest upfront cost but is offset by Victorian Energy Upgrades rebates and lower running costs over the life of the unit. We quote the cheapest viable option alongside any sensible upgrade so you can compare directly.
Repair if the unit is under 8 years old and the failed component is cheap (thermocouple, pressure-relief valve, igniter, anode). Replace if the unit is over 12 years old, or if the failed component costs more than 30-40% of replacement cost, or if the tank itself is leaking. Between 8-12 years it depends on which part has failed and what brand the existing unit is. We tell you honestly on the quote.
You don't apply for a permit yourself. The licensed plumber and gasfitter installing the replacement lodges the BPC Compliance Certificate (plumbing) and Certificate of Compliance (gas, with Energy Safe Victoria) the same day. Those are the equivalent of "permit" for the work and are what your insurer expects to see.
Yes — Victorian Energy Upgrades (VEU) provides rebates for heat pump replacements that displace electric or gas storage units. The rebate amount depends on household electricity consumption baseline, the model chosen, and the displaced unit's fuel type. We confirm eligibility and the expected rebate amount before quoting, and handle the paperwork on your behalf if you proceed.
Yes, and on most Melbourne properties this is now the lowest-running-cost option, particularly when the VEU rebate is factored in. Switching from gas to heat pump usually needs a new electrical circuit (15A or 20A depending on the unit). We coordinate the electrical work with a licensed electrician as part of the replacement quote so you get one fixed price for the whole job.
We disconnect, drain, remove and dispose of the old unit through licensed metal recyclers. You don't need to do anything with it. The disposal is included in the replacement quote.
All major brands sold in Australia — Rinnai, Rheem, Bosch, Vulcan, Aquamax, Dux for gas and electric. Sanden, iStore, Reclaim Energy, Stiebel Eltron, Rheem AmbiHeat for heat pumps. We can replace any brand with any other; switching brands is fine and sometimes makes sense if the existing brand has been unreliable.
