Adelaide's winter mornings, by area
City and coast
The Bureau's West Terrace station has a July mean minimum of 7.6°C and Adelaide Airport 7.1°C. West Terrace averages only 0.3 days a year at 2°C or colder.
Northern plains
Parafield Airport's July mean minimum is 6.3°C, with 9.4 days a year at 2°C or below. Edinburgh RAAF is similar: 6.1°C in July and 8.7 such days.
Adelaide Hills
Mount Lofty, at 685 m, has a July mean minimum of 5.0°C and averages 4.6 days a year at 2°C or below, from 36 years of records.
Why your suburb belongs in the conversation
Because a heat pump draws its heat from the air around the outdoor unit, the coldest mornings where you live are the fair test. We don't publish performance figures for any model. Ask the installer to show you, from the manufacturer's information, how the one they're quoting handles your area's winter lows.
The SA rules a heat pump has to meet
In an established house, any new water heater, heat pumps included, must comply with the standard made under section 66 of the Water Industry Act 2012. We couldn't read the standard itself, so the plumber should confirm the model meets it.
If the heat pump has an unvented storage tank, SA's code calls for new temperature/pressure relief and expansion control valves, with separate drain lines to a visible outlet. A tempering valve goes in on a replacement only where one was fitted before, and bathroom outlets are capped at 50°C. Our tempering valves page explains why.
STCs and REPS
Heat pumps under 425 L can create STCs if the model is on the Clean Energy Regulator's register and the installer meets the state's licensing requirements. Owners usually assign the STCs to an agent for a discount or delayed payment, and certificates are issued until the scheme ends in 2030. They are certificates, not a rebate.
REPS is available to every South Australian, regardless of energy retailer, and moving household water heating to more efficient models or tariffs is one of its activities. We don't quote amounts for either scheme. See STCs explained.
Moving to a heat pump, step by step
Shortlist compliant models
Ask which models meet SA's standard for established homes and appear on the STC register.
Plan where it goes
The outdoor unit needs airflow, a spot for its relief drains to discharge visibly, and some thought about neighbours' bedrooms.
Get the full price in writing
One quote showing the model, the STC discount, any REPS offer, the valves being fitted and what you pay.
Keep the certificates
The plumbing eCOC is due within 7 days. If any gas fitting is involved, such as dealing with an old gas unit, a gas eCOC is due within 30 days.
Questions for an Adelaide heat pump installer
- How does this model handle a winter morning in our suburb?
- Is it on the STC register, and does it meet SA's water heater standard?
- Where will the relief and expansion valve drains discharge?
- Does our home need a tempering valve with this replacement?
- How loud is the outdoor unit, and where would you put it?
What we would do
Start with compliance, not the brochure: the model must meet SA's standard and sit on the STC register. Then judge it against your own suburb's winter mornings, which in Parafield or the Hills are colder than in the city. Finally, ask for a single written quote with every discount shown and the eCOC promised, from a plumber who installs heat pumps every week.