Air source heat pump cost depends on the system you choose, how much heat your home needs and how straightforward the installation is. A price for the unit alone is not a reliable project budget: electrical work, pipework, access, removal of old equipment and other site requirements can all affect the total. In New Zealand, first distinguish between an air-to-air heat pump, which heats rooms directly, and an air-to-water system, which supplies a hydronic heating system. Then compare itemised quotes and estimate electricity use as well as upfront costs.
A complete quote should describe the installed system, not just name a model and give a total. The work may include assessing your home, supplying equipment, fitting indoor and outdoor units, connecting the system, commissioning it and showing you how to use the controls. Some projects also need electrical upgrades, new pipework, access equipment or removal of existing heating.
Ask whether the price includes GST and every part of the proposed work. If something is excluded, such as repairs to an existing switchboard or extra building work, ask how that would be priced if it becomes necessary. A low headline figure can be difficult to compare with a more complete quote unless the scope is clear.
| Cost area | What can affect it | What to check in the quote |
|---|---|---|
| Equipment and system type | Heating capacity, number of indoor units, controls and whether the system is air-to-air or air-to-water | Exact model, included components and any required accessories |
| Installation labour | Site access, unit locations, pipe or duct routes and the amount of work required | Where each unit will go and what installation work is included |
| Electrical work | Whether existing circuits and the switchboard can support the installation | Any electrical work included, excluded or subject to a site check |
| Heating distribution | Existing radiators or underfloor heating, ductwork, or the need for new emitters | Whether the quote includes changes to the distribution system |
| Removal and making good | Old equipment, redundant pipework, wall penetrations and surface repairs | Removal, disposal and finishing work listed separately or included |
| Ongoing use | Heat demand, system performance, operating habits and electricity tariff | Expected electricity use and the assumptions behind any estimate |
“Air source heat pump” describes where a system gets heat from, not one particular indoor setup. For a home heating project, the most important distinction is usually between air-to-air and air-to-water systems. They serve different purposes, so a simple comparison of equipment prices can be misleading.
An air-to-air heat pump transfers heat to indoor air. A wall-mounted single-split system has one indoor unit connected to an outdoor unit and is commonly used to heat a particular living area. A multi-split system can connect several indoor units to one outdoor unit, while a ducted system distributes conditioned air through ducts.
As a general budgeting guide, a single, accessible room is a simpler project than a home needing several indoor units or new ductwork. The final price still depends on the equipment, where the units can be placed and the work needed to connect them. A single unit may also leave bedrooms or closed-off rooms cold, so it is not automatically the right low-cost option for a whole home.
An air-to-water heat pump transfers heat to water, which can then circulate through compatible radiators or underfloor heating. The project cost depends on the heat pump and on the condition and suitability of the existing hydronic system. If radiators need replacing, pipework needs alterations or controls need updating, those items can add substantially to the installation scope.
Ask the installer to assess the required water temperature and the heat output of the existing radiators or underfloor system. The heat pump must be matched to the distribution system and the home’s heat demand. A quote that covers only the outdoor unit and basic connections may not include changes needed for satisfactory heating throughout the house.
Two homes of similar floor area can need different equipment. Ceiling height, insulation, draughts, glazing, layout and the temperatures you want in different rooms all influence the heating requirement. Floor area can be a useful starting point, but it should not be the only basis for selecting a system.
Ask how the installer has assessed your home’s heat loss and how that assessment informed the proposed capacity. Oversizing can mean paying for more equipment than the home needs; undersizing can leave the system struggling to maintain comfort in colder conditions. Request an explanation of any assumptions, including which rooms are expected to be heated and whether doors will usually be open or closed.
The physical installation can change the price too. A long or awkward route between indoor and outdoor equipment, difficult access, limited mounting options or extensive penetrations through walls can require more labour and materials. Outdoor unit placement should allow for servicing and appropriate airflow, while taking account of noise, drainage and the household’s use of outdoor spaces.
For air-to-water systems, the existing heating network adds another layer of assessment. For air-to-air systems, the number and position of indoor units affect how well heat reaches the spaces you use. In either case, ask the installer to identify any work that is conditional on what they find during installation rather than treating it as an unexpected extra later.
The installed price is only one part of the budget. A heat pump uses electricity, and its running cost depends on the amount of heat your home requires, the system’s seasonal performance and the electricity tariff you pay. The outdoor temperature, system settings and condition of the home can also affect actual use.
A useful way to frame an estimate is:
Estimated electricity cost = annual heat required ÷ seasonal performance factor × electricity price per unit.
The seasonal performance factor represents how much useful heat the system delivers over a period for the electricity it consumes. It is more useful for budgeting than relying solely on a laboratory rating, but an estimate still depends on the home and how the system will be used. Ask the supplier to state the assumed heat demand, performance figure, operating hours and tariff. Treat the result as a planning estimate, not a guaranteed bill.
When comparing with current heating, compare the cost of providing similar comfort, rather than comparing a heat pump estimate with the entire household electricity bill. If your tariff changes by time of day, ask how the estimate accounts for your likely schedule. If the system will also provide cooling, consider that use separately rather than assuming it is included in a heating-only estimate.
Insulation and draught control matter because they affect how much heat the home loses. If rooms are cold because of poor insulation or uncontrolled airflow, improving the building fabric may reduce the heat the system needs to provide. Ask whether the heat pump assessment assumes any insulation or ventilation work, and keep those costs distinct from the heating installation when comparing options.
Get quotes based on the same brief wherever possible. If one installer has priced a single wall unit and another has proposed a multi-room system, the totals do not represent equivalent options. Give each installer the same information about rooms, comfort problems, existing heating, insulation and intended use, then ask them to explain any differences in their recommendations.
Build your budget from the complete installed quote, any separate electrical or building work, removal of old equipment and a realistic allowance for work that has not yet been confirmed. Keep the operating-cost estimate separate so you can see both the upfront commitment and likely ongoing use. If quotes differ sharply, ask each installer to explain the system design and exclusions before treating the lowest total as the best value.
Quotes may cover different equipment, heating capacity, numbers of indoor units and amounts of installation work. Differences in access, electrical requirements, existing radiators or ductwork can also affect the total. Compare the detailed scope and assumptions before deciding which quote offers better value.
There is no reliable answer without knowing the home and the work involved. A straightforward air-to-air installation may be simpler than changing a hydronic system, but a multi-room or ducted design can involve more equipment and labour. An air-to-water system’s cost depends partly on whether the existing radiators or underfloor heating can be used as they are.
Your bill can help show your tariff and existing electricity use, but it does not by itself reveal how much electricity a new heat pump will need. Ask for an estimate based on the home’s heat demand and the system’s seasonal performance. Make sure the estimate uses a tariff that reflects how you expect to operate the system.
Insulation usually affects the amount of heat a home needs, which can influence system sizing and future electricity use. It is not necessarily part of the heat pump installation quote, so ask what assumptions the installer has made about the building. If insulation improvements are planned, have the heating requirement assessed with those changes in mind.
Confirm the exact system, the areas it is intended to heat, the installation scope, GST, exclusions and any possible additional work. Ask how capacity was chosen and what assumptions support the running-cost estimate. Also check warranty terms, commissioning and any servicing requirements.
A realistic air source heat pump cost starts with a system suited to the home and a quote that spells out the full installation. Compare air-to-air and air-to-water options only where they meet the same heating needs, and examine the assumptions behind both the upfront price and electricity estimate. Before committing, resolve unclear exclusions and confirm whether insulation, electrical or distribution-system work should be included in your wider home comfort budget.
