Repair or Replace? How to Decide the Fate of Your Old Heat Pump

• The 50% rule suggests replacing your unit if a single repair costs more than half the price of a new system.
• Modern air-source heat pumps now last between 15 and 25 years, whereas older units typically struggle after 10 to 15 years.
• Frequent repairs and rising energy bills often indicate that a system is nearing the end of its functional life.
• Newer technology can reduce electricity consumption significantly compared to aging, inefficient models.
• A professional service can often resolve minor issues and extend the life of a unit that is still in its prime.

Deciding whether to fix a failing appliance or invest in a brand new one is a common dilemma for Auckland homeowners. When the air coming from your vents feels lukewarm on a chilly July morning, or the outdoor unit starts making a racket that bothers the neighbours, the question of whether to repair or replace your heat pump becomes urgent. We understand that this is a significant financial decision. Our goal is to provide a clear, numbers-based framework to help you choose the path that makes the most sense for your comfort and your wallet.

A 2025 analysis of homeowner costs found that most people pay between US$160 and US$651 for heat pump repairs, with an average of about US$405. In contrast, a full system replacement typically ranges from US$6,000 to US$13,000. While these figures are based on overseas data, they illustrate the substantial gap between a quick fix and a total overhaul. In our experience, the smartest choice depends on a combination of the age of your unit, the frequency of recent breakdowns, and the long-term impact on your energy bills.

The 50% rule states that if a single repair cost exceeds half the price of a new system, you should choose replacement. This is a standard industry benchmark used to prevent homeowners from "throwing good money after bad." For example, if you have an older unit and the compressor fails, the cost of the part and the labour to install it might approach the price of a modern, more efficient model. In such cases, the investment in a new system provides better value because you gain a full manufacturer warranty and improved technology.

Another helpful calculation is the $5,000 rule, which involves multiplying the cost of the repair by the age of the system. According to RC Air Conditioning , if the total is over $5,000, replacement usually makes more financial sense. Imagine a 12-year-old heat pump that needs a $500 repair. The calculation results in $6,000, suggesting that your money is better spent on an upgrade. We often see homeowners in Auckland struggle with this when their unit is just outside its warranty period, but looking at the total cost of ownership over the next five years usually makes the decision clearer.

Modern air-source heat pumps typically last 15 to 20 years, with some newer models reaching 25 years if they are well-maintained. This is a significant improvement over older units, which were generally expected to last only 10 to 15 years. This data, cited by Palmetto and the U.S. Department of Housing and Urban Development , highlights why the age of your system is a critical factor. If your unit was installed back when the All Blacks won the 2011 World Cup, it is likely nearing the end of its reliable lifespan.

Auckland's damp, coastal environment can be particularly tough on outdoor units. Salt spray and high humidity can lead to corrosion if the coils are not regularly treated. We have seen systems in coastal suburbs like Mission Bay or Devonport age faster than those in sheltered inland areas. Once a heat pump reaches that 15-year mark, the internal components like the fan motor and compressor have worked through thousands of cycles. At this stage, even a well-functioning heat pump might be significantly less efficient than a modern counterpart.

The most obvious sign that it is time to replace your heat pump is a noticeable decline in its ability to maintain the desired temperature. If you find yourself constantly adjusting the remote or if certain rooms stay stubbornly cold, the system is likely struggling to keep up. This often happens because the refrigerant levels are low or the compressor is losing its mechanical efficiency. While a technician can sometimes top up the refrigerant, a leak in an old unit often signals a systemic failure that is costly to fix.

Strange noises and frequent breakdowns are also major red flags. A healthy heat pump should operate with a steady, low hum. Grinding, squealing, or rattling sounds could indicate a failing motor or a loose component. If you have had to call for a service or repair multiple times in the last two years, you are experiencing the "diminishing returns" phase of the product life cycle. According to Integrity Refrigeration and AC , heat pump replacement becomes necessary when a system requires frequent costly repairs or struggles to provide consistent comfort.

Investing in a new heat pump can lead to dramatic savings on your energy bills because modern technology is far more efficient than the systems of a decade ago. Data from EECA shows that residential hot water heat pumps use around 60 to 75% less electricity than conventional electric systems. While this specific study focused on hot water, the underlying air-source technology is the same. Over a 10-year period, the total cost of ownership for these efficient systems is 27% cheaper than electric cylinders and 21% cheaper than gas.

When you apply this logic to your home's heating and cooling system, the savings add up quickly. An older heat pump might be working twice as hard to produce the same amount of heat, leading to higher energy bills every month. By upgrading to a modern Mitsubishi Electric, Daikin, or Fujitsu unit, you reduce your monthly overheads while improving your indoor air quality. A standard single-split heat pump installation in Auckland typically costs between $1,700 and $4,000, and the resulting efficiency gains can help offset that initial price over the following years.

A comprehensive service can often restore a unit that seems to be failing, saving you from the cost of a full replacement. We have found that many "broken" heat pumps are actually just suffering from neglected maintenance. Dust and dirt buildup on the indoor coils and filters can increase power consumption by 10 to 35%. Our team offers a comprehensive heat pump service for $130 + GST, which includes a thorough inspection of the electrical connections, drainage, and coil cleanliness. This small investment can sometimes add years to the life of your current system.

If you have multiple units at your property, we provide a discounted rate for each additional unit of $65 + GST. During a service, we can give you an honest assessment of whether your system is a candidate for a simple repair or if it is time for an upgrade. We pride ourselves on being straight up with our customers. If a $130 service will get you another three years of comfortable heating, we will tell you. If we see that the compressor is on its last legs, we will provide the information you need to make an informed decision about a new system.

Knowing the local market rates for labour and parts helps you evaluate any repair quotes you receive. Auckland Heatpump Services publishes clear pricing to ensure our customers know exactly what to expect. Our electrician hourly charge is $90 + GST, with a vehicle charge of $25 + GST for the first hour. For urgent situations where your system has completely failed in the middle of a cold snap, our emergency call-out fee is $385 + GST, which includes up to three hours of work. You can find a full breakdown of these costs on our pricing page.

If you decide that replacement is the best path forward, we offer free quotes for supply and installation. We are committed to providing the best value in Auckland, which is why we will price match or beat any written quote for a new system. Whether you are looking for a basic split system or a complex ducted solution, we can help you choose a model that fits your home's layout and your family's needs. Taking the time to get a professional opinion ensures that you don't spend money on a repair that only delays the inevitable, or replace a system that simply needed a good clean.

The decision to replace your heat pump ultimately comes down to a balance of age, cost, and comfort. If your unit is under 10 years old and the repair is minor, fixing it is almost always the right move. However, if you are facing a large bill for a system that is over 15 years old, the benefits of modern energy efficiency and a new warranty make replacement the superior choice. Auckland's climate demands a reliable system that can handle both the winter damp and the summer humidity. By following the 50% rule and keeping an eye on your energy bills, you can make a choice that keeps your home comfortable for years to come.