A heat pump hot water system is an electric tank with a small compressor on top that pulls heat out of the surrounding air and puts it into the water, the same way a reverse cycle air conditioner heats a room. On the Gold Coast, where the air is warm most of the year, that is a very efficient way to make hot water. One clarification before anything else: this page is about a heat pump for household hot water, not a heat pump for heating a swimming pool. They share a name and a principle and nothing else, and if it is the pool you are after, our pool heat pump cost page is the one you want.
Heat pump hot water installed: the price
| Job | Price | What it covers |
|---|---|---|
| Heat pump hot water, supply and install | $2,500 to $4,500 supply + install after STC rebates | Unit, base, plumbing connection, valves, condensate drain, commissioning, Form 4. The electrical circuit is arranged with your electrician and quoted with the job |
| STCs and state rebates | Can knock $1,000 to $2,500 off the sticker | Claimed on your behalf; the installed figure above is after that |
| Repair to an existing heat pump unit | Quoted after diagnosis | Fault codes, fan, compressor and sensor faults. No published figure |
| Electric storage, for comparison | $1,300 to $2,400 supply + install | Cheapest to buy, dearest to run on full tariff |
| Gas continuous flow, for comparison | $1,900 to $3,500 supply + install | Needs gas, endless hot water |
What are STCs and how do they lower the price?
Small-scale technology certificates are the federal incentive for installing efficient hot water. A heat pump earns a number of them based on how much electricity it is expected to save over a standard electric tank, and those certificates have a market value. In practice the installer claims them and takes the value off your invoice, which is what after STC rebates means in the price above. Queensland has at various times run its own rebate on top, and the eligibility and amount change, so we confirm what is current at the time of your quote rather than promising a figure here. Between the two, the reduction can be $1,000 to $2,500 off the sticker, which is most of the gap between a heat pump and a gas unit. The certificates only apply to an approved unit installed by a licensed installer with the paperwork done properly, which is another reason to avoid a cheap install that skips the compliance side.
Why is it the cheapest to run?
Because it moves heat instead of making it. A standard electric element turns one unit of electricity into one unit of heat. A heat pump uses its electricity to run a compressor and fan, and pulls several units of heat out of the air for each unit of power it draws, so the same hot water costs a fraction of the electricity. The warmer the air, the better it works, and the Gold Coast rarely gets cold enough to hurt it. If you have rooftop solar, the unit can be timed to run in the middle of the day on your own generation, which brings the running cost down again. We are not going to put a dollar figure on your savings here, because they depend on your tariff, your usage and your solar, and anyone who quotes you a saving without knowing those is guessing. What we will say is that of the four common systems, this is the one that costs the least to run, and by a clear margin for a household that uses a lot of hot water.
Where does it go, and how noisy is it?
This is the honest conversation to have before you buy. The compressor and fan on top of the tank make a noise when the unit is running, similar in character to a small air conditioner outdoor unit, and the unit runs for a few hours a day to heat the tank. It is not loud, but it is not silent either, and it matters where it sits. A heat pump under a bedroom window, or right against a neighbour's fence line near their bedroom, is a recipe for a complaint. It also needs airflow, because it works by drawing heat out of the air, so it cannot be boxed into a tight cupboard or a corner with no clearance. The best spot is an open outdoor position with room around it, away from bedrooms on both sides of the fence. Most units let you set the hours they run, so a unit on solar can be timed to the middle of the day when nobody minds a hum. It also produces a small amount of condensate, which is plumbed to a drain rather than left to drip on the slab. We look at all of this at the quote, and if the only spot available is a bad one, we will say so rather than install a unit you will resent.
What the $2,500 to $4,500 covers, and what it does not
The unit with its warranty registered to you, delivery and removal of the old tank, the base, connection to the hot and cold pipework, tempering, relief and pressure limiting valves where required, the condensate drain, commissioning, a temperature check at the taps, the STC paperwork and the Form 4. In Queensland a like-for-like hot water replacement is notifiable work, so the licensed plumber lodges a Form 4 with the QBCC afterwards. Our QBCC plumbing licence is 15243081. There is no gas on a heat pump, so no gas compliance certificate is involved. What the figure does not include is the dedicated electrical circuit the unit runs on. That is licensed electrical work, arranged with your electrician and quoted with the job rather than buried in the supply and install price, and it comes with its own electrical certificate.
What takes a heat pump job to the top end?
A larger tank for a bigger household, a longer electrical run to the switchboard on the electrician's side of the quote, a change of position from where the old tank stood, and difficult access for a unit that is taller and heavier than the electric tank it replaces. A straight swap onto the same pad with the switchboard nearby is the bottom of the range.
When is a heat pump the wrong choice?
When there is nowhere sensible to put it, when the household is small enough that the running cost saving would take a long time to repay the extra purchase price, or when you need hot water back today and the unit is not in stock. In those cases an electric storage tank at $1,300 to $2,400 supply and install is the honest recommendation, and we will make it. If the house runs gas and you are happy with it, gas storage at $1,800 to $3,200 or continuous flow at $1,900 to $3,500 both remain sound choices. A heat pump is the best buy for a mid-sized or large household with a good outdoor position, especially with solar on the roof.
Weighing up a heat pump? Call Hills Plumbing & Gas on 0472 657 042 or book through our Hot Water Systems service page. I will check the position, confirm the rebates that apply on the day, and give you one fixed price after the STCs come off. Jieye.