A replacement that fits your home, and the whole quote.

Replacing like for like or changing system type

A like-for-like replacement can keep the planning straightforward, but it still needs the existing connections, location and installation requirements checked. A new model may have different dimensions, connections or service clearances. Ask which changes are included and which would be quoted separately.

Changing from gas or electric resistance storage to a heat pump brings a different set of questions: outdoor space, airflow, noise, power supply, drainage and heating schedule. If you already have rooftop solar, ask how the proposed system's controls and your tariff affect when it heats. An installer should explain the choice in relation to your home.

Capacity is about the busy part of your day

Tell the plumber how many people use hot water, how many showers run together, whether you use a bath and when demand peaks. A home with staggered showers can have a different requirement from the same-sized household using multiple bathrooms together.

Storage capacity, usable delivery and recovery rate aren't interchangeable. A continuous-flow system is selected using flow and temperature-rise requirements, rather than a stored-water litre figure. The system selector prepares these details for the installer; it doesn't calculate a compliant size.

Ask for these items in writing

For a new build or renovation, include the stage of construction and who coordinates other trades. For an occupied home, ask when the supply will be interrupted and what happens if an unexpected site issue is found. A clear written variation process is useful before work begins.

• Exact make, model and system capacity.
• Removal and disposal of the old unit.
• Plumbing, valves, pipework and any location changes.
• Electrical or gas work and who carries it out.
• Access, base, drainage and installation requirements.
• Commissioning, instructions and applicable compliance documentation.
• GST, warranty terms and any incentive assumptions.

Separate the quote from the rebate

Ask for the full installed cost, the incentive applied, and the remaining amount as separate figures. Eligibility depends on the scheme, replacement circumstances, product and participating provider. A headline offer doesn't establish your home's eligibility.

Keep the model information, invoice, commissioning details and warranty documents together after installation. Your contract and workmanship arrangements are with the independent provider, who should explain who to contact if something needs attention.

Your questions, answered