The heat pump installation process, step by step

Knowing what a good installation looks like makes it much easier to judge quotes and spot shortcuts on the day. This guide follows a typical high-wall split install in a New Zealand home. Multi-split and ducted jobs follow the same pattern with more units, more pipework and more time.

How long does a heat pump installation take?

A simple back-to-back install, where the indoor and outdoor units sit on opposite sides of the same wall, typically takes an experienced installer about three to four hours. Longer pipe runs, upstairs units or awkward access can stretch that to a full day, and ducted systems often take several days depending on the number of zones.

What are the steps in a heat pump installation?

Who is legally allowed to install a heat pump in NZ?

Two parts of the job carry specific requirements. The electrical connection is electrical work that must be done or supervised by a person registered with the Electrical Workers Registration Board, and you should receive an electrical Certificate of Compliance (CoC) for it. The refrigerant work must be done by someone trained and certified to handle refrigerants, because the gases are regulated and harmful if released.

Many heat pump companies employ both trades, and others, including us, manage the job and use a contracted installer for the electrical and refrigerant work. Either is fine, but whoever you use, ask who will do each part and ask to see their registration or certification. Our guide to choosing an installer lists the checks.

Do I need a building consent for a heat pump?

Usually not. A standard domestic heat pump installation is normally carried out without a building consent, but the work still has to comply with the Building Code and electrical safety rules. Exceptions can apply for work affecting structure, fire separation or weathertightness, and for apartments, where the body corporate's rules also matter. MBIE's exempt building work guidance is the reference, and your council can confirm.

District plans can also limit noise at your boundary, which affects where the outdoor unit goes. See our noise, placement and council rules guide.

What should I check on installation day?

• The indoor unit is level, securely fixed and positioned where you agreed.
• The wall penetration is sealed inside and out, so no draughts or water get in.
• Pipework outside is neatly covered and supported, not left in loose tape.
• The condensate drain runs somewhere sensible, not onto a path or against the house foundation.
• The outdoor unit is level, has clear space for airflow and is secure on its feet or bracket.
• The system has been run in heating mode and blows warm air within a few minutes.
• You have the manual, warranty details, the installer's contact details and, for the electrical work, the CoC.
• You know how to remove and clean the filters. Our filter cleaning guide covers it.

How do I prepare for the installer?

• Clear furniture from the wall where the indoor unit goes and from the path to the outside wall.
• Clear plants or stored items where the outdoor unit will sit.
• Make sure the installer can reach the switchboard and, if needed, the ceiling or underfloor space.
• Plan for the power to be off for part of the day while the electrical connection is made.
• Keep pets and children away from the work area; there will be drilling and dust.

What can make an installation cost more?

Quotes usually assume a standard install. Anything that adds labour or materials adds cost: long pipe runs (priced at around $50–$80 per metre for extra pipe), upstairs indoor units, high wall brackets, switchboard upgrades, concrete walls, or ducting through finished ceilings. Our heat pump cost guide covers these extras in detail.