What is the Life Expectancy of a Heat Pump?

Heat pumps are the most popular form of heating and cooling for New Zealand homeowners, providing heating and cooling functions suitable for the country's varying climate at the lowest energy cost. These remarkable systems typically have an expected useful lifespan of between 10 to 20 years and like most mechanical equipment, have several factors that can influence their longevity. From climate conditions and frequency of use, to maintenance practices, a range of elements contribute to how long a heat pump will continue to serve your home. For those considering investing in a heat pump, understanding these factors may help in calculating payback and highlight the benefits of maintenance so you can ensure you get the best value from your purchase. 

OneAir has been installing and servicing heat pumps across the country for over 10 years and in that time has picked up some useful tips from the many thousands of heat pumps it has come across during that time; insights which may be able to extend the lifespan of your system and save you thousands on premature replacement costs. The main ones are listed below. 

Factors Affecting Heat Pump Lifespan

1. Climate Conditions: New Zealand's unique climate plays a significant role in heat pump durability. Coastal regions, with salt-laden air, and sulphurous ones like Rotorua can cause corrosion, particularly in outdoor units, which may shorten the life of a heat pump. In contrast,  regions with dry, cooler winters and temperate summer temperatures pose less of a corrosion threat, potentially increasing their lifespans.

Heat pumps also face increased demands in areas with temperature extremes, such as inland areas with hot summers or the South Island's sub-zero winters. These conditions will require the heat pump to work harder to achieve the desired set point temperature, which can also impact the system's durability over the long term.

2. Usage Frequency and Intensity: How often you use your heat pump is a significant factor in determining its lifespan. Homes that rely on heat pumps year-round for both heating and cooling may experience more wear and tear than homes using them only occasionally. As you can imagine, the more hours a heat pump runs, the faster components like the compressor and fans will wear out, especially if the unit is used at maximum capacity.

3. Installation Quality: Proper installation by an experienced HVAC technician is crucial for any heat pump’s longevity. It begins by selecting the correct system size, as an undersized system will have to work harder to achieve even reasonable set point temperatures, thereby placing undue stress on the system from day one and contributing to increased wear and tear and most likely a shortened lifespan.

Even heat pumps that are much larger than what is required for the space are not a good idea as they are prone to a performance trait known as ‘short-cycling’ as they turn on and off repeatedly, which is again detrimental to long lifespans.

Selecting a good location for an outdoor unit is also crucial, as they need ample space and good ventilation on all sides to function at their best. Access to rain and sun is also preferred as it naturally washes off contaminants that can cause rust while the sun dries the system quickly to avoid rust forming. Similarly, units underneath a balcony or deck run the risk of where water drops on them without direct sunlight being able to dry the moisture. 

Ensuring the system is correctly sized for your home and that the outdoor unit is sitting up on PVC feet to allow airflow underneath the unit can further help maximise its longevity.

4. Maintenance Practices: Regular maintenance is one of the most significant factors influencing a heat pump's lifespan. Cleaning or replacing filters, keeping the outdoor unit free from debris, and scheduling annual professional inspections are essential steps to ensure smooth operation. Filters should be cleaned at least once every  three to four months, depending on usage, as clogged filters can reduce efficiency and increase strain on the compressor.

If you live in an area with a busy road, nearby construction, or even with pollen, dust, and moisture regular maintenance is even more critical to prevent airflow blockages and premature corrosion.

5. Usage Practices: Setting extreme set point temperatures will shorten the lifespan of a heat pump as it will be continuously working at maximum speeds to try to reach set points that are   impossible to achieve.

Similarly, in small to medium-sized rooms, leaving ranch sliders or doors wide open will again force the system to work harder than it would normally need to have the windows and doors closed, allowing the desired set point temperature to be achieved. 

Curtains too, play a useful role, as thermal curtains can help trap heat in that would otherwise escape via (especially single pane) glass windows in winter, while in summer, dark curtains can help block the direct sunlight that would otherwise add significant heat load to the room the air conditioning is trying hard to cool.

Types of Heat Pumps and Lifespan Variations

Heat pumps come in various types, each with unique characteristics and lifespan expectations:

1. Split System Heat Pumps: Split systems are among the most common types in New Zealand homes, ideal for single rooms or smaller spaces. These systems typically last around 10 to 15 years with regular maintenance. However, if well cared for, OneAir has customers with models that are 20 years or more and they are still going strong.

2. Ducted System Heat Pumps: Ducted systems are designed to heat or cool entire homes and are often hidden within the ceiling space. Ducted systems may last 15 to 20 years, although the ductwork itself may require periodic inspection for leaks or blockages, which can impact overall efficiency and reduce lifespan.

3. Geothermal Heat Pumps: Though less common in New Zealand, geothermal heat pumps are highly durable, with lifespans averaging 25 years or more. These systems use the stable underground temperature to heat and cool a home, resulting in less wear on the compressor and other components. However, geothermal systems can be more expensive to install initially.

Signs Your Heat Pump is Nearing the End of Its Lifespan

Identifying when your heat pump may need replacing can save you from unexpected breakdowns and rising utility costs. Common signs that a heat pump is reaching the end of its life include:

• Increased Vibration and/or Noise Levels: If your heat pump is making more noise than usual, it may indicate worn components, such as the compressor or fan motor.

• Reduced Efficiency: A noticeable drop in heating or cooling performance, even after maintenance, could signal a system is on its last legs.

• Frequent Repairs: If you're calling for repairs more than once every two years, the cumulative costs may indicate it's time for a replacement.

• Higher Energy Bills: Older systems lose efficiency over time, leading to higher utility costs. When a system has to work harder to deliver the same level of comfort, replacement may be the more cost-effective choice.

Tips for Extending Heat Pump Life

By following a few best practices, homeowners can prolong the life of their heat pump and enhance its efficiency.

1. Set Moderate Temperatures: Avoid setting extreme temperatures that force the unit to work at maximum capacity. During winter, set your heat pump to around 18–20°C; in summer, aim for 22–24°C. These settings not only save energy but also reduce strain on the unit.

2. Schedule Annual Professional Maintenance: An annual maintenance check by a qualified technician helps catch potential issues early and keeps your system operating at peak efficiency. In New Zealand, it's best to schedule this before the peak summer or winter season to ensure the system is ready for heavier use.

3. Keep Outdoor Units Clear: Ensure that the outdoor unit has adequate airflow by regularly clearing away debris, leaves, and branches. An outdoor unit in an exposed area may benefit from a cover to protect it from harsh weather, especially in coastal regions where salt exposure can lead to corrosion.

When to Consider a Replacement

Replacing a heat pump can be a big decision, but several scenarios make it clear when it's time to upgrade.

• High Repair Costs: If repair costs exceed 40% of a new unit's price, replacement may be a more economical choice. Almost all brands in NZ come with a 5-year warranty period, meaning total peace of mind for this period of time with all repair costs being borne by the manufacturer and/or the installer 

• Enhanced Energy Efficiency: Newer models are designed with advanced technologies that provide better energy efficiency, which can lead to lower electricity bills.

• Available Rebates or Incentives: In some regions, EECA rebates are available to encourage homeowners and landlords to switch to energy-efficient systems, which can subsidise up to $3000 off the cost of an approved heating system. You must be a low income earner or live in a low income area and be in a house built before 2008 to qualify.

Upgrading to a modern heat pump often provides a return on investment through reduced energy bills and improved comfort and indoor air quality, making it worthwhile for many New Zealand homeowners.

Making the Most of Your Heat Pump Investment

Understanding what affects the lifespan of your heat pump allows you to make informed decisions about maintenance, repair, and replacement. You can maximise your system's performance and longevity by selecting the right type for your climate, keeping up with routine maintenance, and using energy-efficient practices. For New Zealand homeowners considering a heat pump, this long-term investment can provide reliable comfort for many years when managed well. Should you need help and some expert advice on which heat pump is right for you, reach out to one of  the friendly OneAir team  at (0800) 663247, WhatsApp 0204 663247 or email  hi@oneair.co.nz.