Most heat pumps don't die overnight.
More often, the signs creep in slowly. Maybe the living room doesn't seem to get as warm as it used to, or perhaps the power bills have been creeping upwards, or you've had to call someone out twice in the last couple of years. Sometimes it's simply that the unit is starting to show its age, and you're wondering whether it's worth spending more money on repairs.
The answer isn't always straightforward.
Many problems that people assume mean it's time for a new heat pump are relatively minor and inexpensive to fix. Equally, there comes a point where continuing to repair an ageing system makes less financial sense than replacing it with a newer, more efficient model.
This guide explains when a repair is worthwhile, when replacement makes more sense, and the factors we consider when helping Waikato homeowners decide.
How long should a heat pump last?
Most quality heat pumps have an expected lifespan of around 12-15 years. Some systems last considerably longer, particularly when they've been installed correctly and serviced regularly.
We've seen well-maintained units still heating homes reliably after twenty years. We've also seen systems struggle after ten years because they've never been serviced or have spent years running flat-out in homes where they were undersized from the beginning.
Age alone doesn't determine whether a heat pump should be replaced. What matters is the overall condition of the system, the cost of repairs, and how efficiently it's operating.
Problems that are usually worth replacing
Not every issue requires a new unit.
In fact, many common faults are relatively straightforward to fix.
These include:
Dirty indoor coils and filters: Poor airflow can make a heat pump seem like it's failing when all it really needs is a proper clean and service.
Blocked drain lines: Water leaks from the indoor unit are often caused by blocked drains rather than anything major.
Faulty sensors: Temperature sensors occasionally fail, but replacing them is usually straightforward.
Electrical components: Capacitors, circuit boards and other components can wear out over time, but repairs are often far cheaper than replacement.
Fan motors: Indoor or outdoor fan motors sometimes fail, particularly in older systems, but replacing them can extend the life of the unit considerably.
If the repair cost is relatively modest and the rest of the system is in good condition, repairing the unit is usually the sensible option.
When replacement makes more sense
There comes a point where repairs become harder to justify.
Your heat pump is over 15 years old: Older systems are generally less efficient and replacement parts can become harder to source. Even if a repair is possible, it may not represent good value.
You've had multiple breakdowns: One repair isn't unusual. But if you're calling someone out every winter, it's worth stepping back and asking whether you're throwing good money after bad.
Your power bills keep climbing: Modern inverter heat pumps are significantly more efficient than units installed fifteen or twenty years ago. Replacing an older system can sometimes reduce running costs enough to offset part of the upfront investment over time.
The compressor has failed: The compressor is essentially the heart of the heat pump. Replacing it can be expensive, and on older units, the repair cost may represent a significant proportion of the price of a new system.
Parts are becoming difficult to find: Eventually manufacturers stop producing components for older models. At that point, repairs can become increasingly expensive or impossible.
One simple guideline many homeowners use is the 50% rule.
If the cost of repairing an older heat pump is more than about half the cost of replacing it, replacement usually makes more sense.
That's not a hard-and-fast rule, but it's a useful starting point.
For example, spending $600 repairing a ten-year-old system may be entirely reasonable. Spending $2,000 on a fifteen-year-old unit that's already had several repairs starts to become harder to justify.
Need an expert opinion?
At Aircon Group Waikato, we service, repair and replace heat pumps throughout Hamilton, Cambridge, Te Awamutu and the wider Waikato region.
If your heat pump isn't performing like it used to, we'll inspect the system, explain what's going on, and give you a straightforward recommendation. Sometimes that means a simple repair. Sometimes replacement makes more sense.
Either way, we'll help you make an informed decision.
Call us on 0508 224 7687 or request a quote online.
FAQ's
Q: Is it worth repairing a 15-year-old heat pump?
A: Sometimes. If the unit has been reliable and the repair is relatively inexpensive, it can still be worthwhile. But if major components have failed or the system has needed several repairs recently, replacement is often the better long-term investment.
Q: Can a heat pump last 20 years?
A: Yes. Quality systems that are serviced regularly can last twenty years or more. Efficiency generally declines over time, however, and older units won't perform as well as modern models.
Q: Is a new heat pump cheaper to run?
A: Usually, yes. Improvements in inverter technology and efficiency mean modern systems often use less electricity to deliver the same amount of heating and cooling.
Q: What part of a heat pump is most expensive to repair?
A: The compressor is typically the most expensive component. On older systems, compressor replacement often prompts a conversation about whether replacement would provide better value.