How to Choose the Best Heat Pump in NZ: A Practical Guide

4 September 2025

Choosing the best heat pump in NZ can feel like a complicated task with so many models, brands, and installers available. Yet the process is simpler when you break it down step by step. By focusing on size, efficiency, installation quality, and lifetime costs, you’ll reduce uncertainty and get reliable heating that fits your home.

Heat pumps are now the most common heating option in New Zealand because they combine lower running costs with improved comfort. Data from the Energy Efficiency and Conservation Authority (EECA) shows that a well-sized and properly installed heat pump provides cheaper heating compared with portable heaters or older forms of heating. This makes them a smart choice for both homeowners and landlords.

Below, we’ve created a practical guide. We’ll cover the questions you need to ask, the checks you should make, and the habits that keep your system running well.

Start With the Right Question: What Do You Need the Heat Pump to Do?

The first decision is to identify your main heating or cooling needs. This single step sets the direction for every later choice, from unit size to installation cost. Many homeowners in New Zealand skip this stage and end up with a system that either does too little or costs more than it should.

• Single room heating: If you want to keep one space warm, such as a living room or bedroom, a wall-mounted split unit is often enough. These systems are affordable to install and give focused comfort in the area you use most. They also suit rental properties where only one or two rooms need heating.
  
• Whole-house heating: Families often need more than one room solution, especially in larger homes. Multi-split systems link several indoor units to one outdoor unit, while ducted systems deliver even heating throughout the house. These options cost more upfront but pay off with consistent temperatures across all rooms.
  
• Combined heating and cooling: In warmer regions of New Zealand, air conditioning during summer matters as much as winter heating. A heat pump that provides both ensures year-round comfort and reduces the need for extra appliances.

Once you know the purpose, you’ll understand the level of investment required. A single-room system suits tight budgets but may not cover the whole household’s needs. A full ducted installation is more expensive but eliminates cold spots and creates a balanced environment. Deciding on purpose early avoids wasted money and ensures you get a solution that matches your lifestyle.

Get Sizing Right Before You Compare Brands

Correct heat pump sizing in NZ is critical. Even the best brand will fail if the capacity is wrong. Undersized units cannot keep up in winter, while oversized ones cycle too often, causing discomfort and early wear.

A heat pump that is too small will run nonstop as it tries to reach the set temperature. This continuous strain leads to higher electricity bills, shorter lifespan, and lower comfort levels. On the other hand, a heat pump that is too large will heat the room too quickly and then shut off, only to restart soon after. This constant start-stop cycle wastes energy and leaves the space feeling uneven.

To size a system properly, you should:

• Measure the room’s length, width, and height to calculate its total volume.
  
• Consider the number and size of windows, as glass allows more heat loss.
  
• Review insulation in walls, ceilings, and floors. Poor insulation can increase heating demand by 30 per cent or more.
  
• Think about location. Homes in colder regions like Southland or Central Otago need higher capacity than homes in Auckland or Northland.

After gathering these details, an installer should confirm kilowatt requirements using recognised calculation tools, not rough guesses. Reliable installers will perform this check before giving a quote. If a company recommends a unit without measuring your rooms, treat that as a warning sign. Correct sizing is the foundation for efficient heating and long-term comfort.

Compare Efficiency Figures, Not Marketing Claims

Efficiency numbers matter more than brand slogans. Always compare seasonal coefficients, which measure how much heating output you get per unit of electricity.

• COP (Coefficient of Performance): Heating efficiency under standard conditions.
  
• HSPF (Heating Seasonal Performance Factor): Seasonal efficiency over a heating season.
  
• SCOP (Seasonal COP): Europe-based standard that shows efficiency at different outdoor temperatures.
  

For New Zealand, ask for efficiency values tested at low outdoor temperatures. Many regions reach near-zero temperatures in winter mornings, so this figure matters more than the mild-climate rating.

Independent tests give the most reliable view. Use these rather than relying on marketing claims.

Check Tested Reviews and Local Model Availability

Not every international model is supported in New Zealand. Choosing a model without local service support can cause issues when you need repairs or parts.

When researching:

• Look for independent review sites that compare heat pumps in NZ.
  
• Confirm the availability of parts and servicing for your chosen brand.
  
• Ask if local technicians are trained and certified for the model you plan to buy.
  

Availability also affects warranty claims. A warranty is only useful if there is a service centre that honours it.

Consider Noise, Controls and Smart Features

Comfort is more than temperature. Noise and ease of control also matter.

• Noise: Indoor units list decibel levels. Bedroom units should be under 25 dB in quiet mode. Outdoor units should also be checked, especially if close to neighbours.
  
• Controls: Look for basic timer functions and remote scheduling.
  
• Smart features: Some brands offer Wi-Fi control, but check if the app is supported in New Zealand.
  

Quiet operation is essential for bedrooms and offices. Controls that let you set and forget reduce wasted energy.

Decide on Single Split, Multi-Split or Ducted Systems

When choosing the best heat pump in NZ, the system type matters as much as brand or size. Each option suits different budgets, property layouts, and household needs.

• Single split systems: These are the most common in New Zealand homes. A single outdoor unit connects to one indoor unit, usually mounted on a wall. They are cost-effective, simple to install, and ideal for heating or cooling one key space such as a lounge, office, or master bedroom. 

For smaller households or rental properties, a single split unit can often provide enough comfort without the expense of a larger system.

• Multi-split systems: These connect one outdoor unit to several indoor units placed in different rooms. They are useful for medium-sized homes where multiple spaces need heating, but roof space or budget make ducted systems less practical. Installation is more complex than single splits, and capacity must be shared across the units. 

This makes correct design important to avoid weak performance when several rooms are used at once.

• Ducted systems: These provide the most even and discreet form of heating. A central indoor unit connects to a network of ducts hidden in the ceiling or under the floor. The air is delivered through small vents in each room.

Ducted systems create balanced comfort across the whole house, but they cost more to install and usually require roof or floor space. They are popular in new builds and renovations where the ducts can be fitted during other construction work.

Your choice should reflect budget, available space, and long-term plans. Single split systems are the easiest way to start, but they may not suit families who need full-home heating. Multi-splits add flexibility but require careful design. Ducted systems deliver the best comfort and resale value, but they work best when planned alongside other building upgrades.

Insist on Quality Installation and Proper Commissioning

The best system will underperform if installed poorly. Poor placement of the outdoor unit or incorrect refrigerant levels can reduce efficiency by up to 20 per cent.

When dealing with heat pump installation in NZ:

• Ask for a written commissioning report.
  
• Confirm that installers are licensed.
  
• Check that refrigerant pipes are insulated and protected.
  
• Ensure airflow is not blocked by fences, plants, or roof structures.
  

Good commissioning includes checking refrigerant charge, airflow balance, and thermostat calibration. Don’t accept shortcuts.

Check Warranties and Local Service Support

Warranties vary widely. Some are long, but they only help if you can access support.

Before purchase:

• Confirm local service centres exist for the brand.
  
• Register your unit and store paperwork.
  
• Ask what the warranty covers, including parts and labour.
  

A long warranty with no local service is not worth the paper it’s written on. Choose brands with proven support networks in New Zealand.

Factor in Lifecycle Cost, Not Only Purchase Price

A cheaper system upfront may cost more over time. Consider the full cost of ownership:

• Purchase price: The cost of the unit and installation.
  
• Running cost: Annual electricity use multiplied by your local rate.
  
• Maintenance: Filter cleaning, servicing, and occasional part replacement.
  

Even small differences in COP ratings translate into noticeable savings when multiplied across years of use.

For example, two units with similar prices can differ by $100 or more per year in electricity bills. Over ten years, that’s $1,000 saved by choosing the more efficient model.

Choose Lower GWP Refrigerants and Relevant Standards

New Zealand promotes the use of low-GWP refrigerants to cut greenhouse gas emissions. Many older systems use gases with a higher impact.

When comparing models:

• Prefer refrigerants with low GWP, such as R32.
  
• Check if the unit complies with current efficiency and safety standards.
  
• Ask your installer which refrigerant your unit uses and how it affects servicing costs.
  

This choice reduces long-term environmental impact and keeps your system aligned with current standards.

Plan Seasonal Use and Simple Maintenance Habits

Maintenance protects your investment and keeps efficiency high.

• Clean filters every few months.
  
• Clear leaves and debris from outdoor units.
  
• Check drainage lines to prevent blockages.
  
• Arrange annual servicing with a professional.
  
• Keep a simple log of servicing and faults.
  

These small habits help avoid breakdowns and extend system life. They also maintain high heat pump efficiency across the year.

Upgrade Your Comfort: Book an Expert Assessment Today

Choosing the best heat pump in NZ is less about chasing brand names and more about following a clear process. Correct sizing, tested efficiency, quality installation, and local service support give you the best outcome.

At Hamilton Aircons, we guide you through the process with a full home assessment. We measure your rooms, check insulation, and recommend the right capacity for your space. We provide written quotes, commissioning plans, and servicing options to keep your system running well.

Heating and cooling are big household expenses. Making the right decision saves money, protects comfort, and lowers stress during winter.

Book an assessment today and let us show you how the right system changes the way your home feels. The best heat pump in NZ is the one that fits your home, your budget, and your comfort goals.