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Your ultimate swimming pool heat pump guide

Installing a swimming pool heat pump gives you wonderfully warm water year-round using less energy and less maintenance than you might expect.

That’s right. 

Heat pumps are much quieter, more efficient, and more durable these days than ever before. Now your family can really make the most out of your backyard oasis. 

So here’s everything you need to know about choosing and installing your heat pump. 

Plus, you’ll find tips and quotes throughout from our in-house technical expert, Doug Goddard.

In this guide to your swimming pool heat pump:

Or are you looking for information about pool pump troubleshootingYou’ll want check its guide.

What is a swimming pool heat pump?

Swimming pool heat pumps do exactly what they say on the tin: they heat your swimming pool

They need to be hardwired into your pool’s electrical and plumbing systems, on a flat surface, and with enough space to circulate air around them. 

The way they heat pools depends on the type of pump. Typically, you’ll find gas, electric, solar, boiler, or heat pump options. 

We recommend heat pumps as they are usually more efficient, emissionless, and can require less maintenance.

How does a swimming pool heat pump work?

The first step, is the inverter pulling in air from their environment. 

Then a heat exchanger transfers the warmth from the air to the cold water pushed through its plumbing by the pool pump

Next, the inverter adjusts the heater’s fan and compressor speed as the water temperature gets closer to the desired temperature, slowing down as it reaches the right level. 

The warm water is then returned back to the pool. Finally, by automatically adjusting its output, the inverter heat pump uses the least amount of energy it needs to get your pool to your ideal temperature. 


Are swimming pool heat pumps worth it?

“Heat pumps are worth installing for three reasons: they allow you to make the most of your pool year-round, they are arguably the cheapest way to heat your pool, and if you have any injuries, aches or pains, a warm swimming pool can be great therapy.” 

New Zealand gets pretty chilly in the winter, particularly if you’re down south. So relying on a nice outdoor temperature to swim in your pool might put it out of action for six months or more every year.

Having a nice warm pool means you can enjoy it year-round. It’s also much more comfortable for kids and elderly parents that might fancy a dip between the seasons. 

Are pool heating pumps noisy?

Over to you, Doug. 

“They used to be! A couple of decades ago, your pool heating pump might’ve reached around 80 or 90 decibels. Nowadays, inverter pumps are smarter with energy efficiency and the fans slow down as they reach their temperature. They might reach around 50 decibels, the kind of levels that allow you to have a conversation without raising your voice.”

Pool pumps were once as loud as a lawnmower. But technology has evolved, and now, you can enjoy a nice and warm pool without the disruption

What size heat pump do you need for swimming pools?

It’s a good idea to get a professional opinion before investing in your pool heat pump, but here’s an idea of what’s involved. The swimming pool heating calculations you’ll need to do depend on a few factors.

The shape of the pool must be considered, as well as its length, width, depth, and volume, and whether it’s an inground or above ground pool. How long your desired swim season is will also affect the size heater you need for your pool. 

Other features might need to be taken into account like whether there’s overflow (if you have an infinity design, for example), and your electrical setup. 

To make things easier, our expert friends at Hayward provide an interactive calculator that figures it out for you. Try it out here.

Or you can reach out directly to one of our trusted local dealers for tailored advice specific to your situation.

How much will your pool heater cost?

Typically, swimming pool heat pump units need to be quoted based on the size and shape of your specific pool. Their upfront cost and the running costs are hugely dependent on what you need and how you look after your pump. 

“In terms of the running cost, this can vary, as it is affected by ambient temperature which is of course, changeable. Obviously when it’s colder outside, the heat pump will need to work harder. 

But heat pumps these days are much more energy efficient and cheaper to run than they used to be. The inverter pumps we see today use a lot less power to get much more consistent temperatures, and can even protect themselves from the frost.”

The cost to run your heat pump will vary based on where you live and the time of year that you run the pump.

For example, running your swimming pool heater pump during winter in the South Island will cost more than keeping the same pool warm during summer in Northland. 

And if your pool is inground, some of the heat is contained within the surrounding walls. Above ground pools lose their heat faster than walls buried in the ground, as there’s less insulation. 

“As a general rule of thumb, it costs roughly the same to heat your pool up from cold as it does to maintain the temperature for a week.”

How to install a heat pump for a swimming pool

Your swimming pool heat pump will need to be hardwired into your electrical and plumbing systems, so it’s best to get an experienced professional to do this safely for you. 

Here’s what’s involved:

  • an electrician will need to run a separate cable and circuit that fits your pump and is connected to your mains supply.
  • a plumber will need to connect the heat pump to the pool’s main return line. The water should flow through the pool pump, filtration system, then the new heater, and back into your pool via any chlorination systems.

Your heater will become a core part of your pool equipment, so make sure you get it installed properly and safely. 

Common swimming pool heat pump errors you might come across

If you install your heat pump properly and maintain it well, you shouldn’t come across many issues.

But in the unlikely event that something does go wrong, it’s probably often to do with flow issues.

“Issues with water flow can cause the heater pump to turn itself on and off unnecessarily. It’s usually responding to a problem somewhere else in the pool, and because it’s not receiving enough water to heat, it responds accordingly.”

Some pool cleaners use the power from the pool pump system to move around the pool. They can sometimes fill up the pool’s skimmer baskets quickly and cause a clog.

This clog slows the water flow into the heater, making it turn itself off. 

“One advantage of the Dolphin robotic pool cleaners we carry is that it operates independently from the other pool equipment which prevents this from happening.”

If your water flow isn’t the problem, your heater pump should give you some indication as to the source:

“Most pumps have a display and their own set of error codes. You can use these to help diagnose the problem.” 

And if you’re still unsure, you can always get in touch with one of our trusted dealers for help.

What is the best swimming pool heat pump?

Hayward is the best brand of swimming pool heat pumps in New Zealand. 

With top of the line inverter heat pumps offering energy efficiency, quiet settings, long-lasting hardware and extra protections against unpredictable weather, you’re sure to find the right option for you.

Check out our range.

Invest in quality pool products with professional installation

Hayward and Dolphin lead the way when it comes to quality pool heat pumps. 

Check out our selection that you can buy from trusted dealers here in New Zealand

To make sure you’re getting the best pump to meet your needs and get it installed by a professional, you’ll want to work with the most experienced in the business.

Find your trusted local Dolphin Pacific dealer via our directory.

About the author
Adrian Hill
Adrian Hill

Hey! I'm Adrian, founder and pool expert here at Dolphin Pacific. I love spending time with family, fishing, and have been known to brew my own beer.

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