So, you have bought an above ground pool, probably an Intex type pool, that sits on your lawn. You have filled it with water, connected up the filter pump and you and your family are all ready to climb that ladder and step in. But then you hear “it’s freezing cold! I am not going in that!”.

Sound familiar? You need a heater. In this article we will discuss the various options for heating a garden above ground pool. We are talking about the type of pool like the one pictured below, you can buy them from us or from Argos, Toys r us, B&Q that sort of thing. Typically 8ft to 18ft round with a combined paper filter and pump.

Brace yourself…

If  your pool is in the 8ft to 12ft bracket then brace yourself: The heater is going to cost more than the pool. Infact regardless of how big your pool is, if you want a really good, efficient heater it is going to cost way more than the pool. We will not be discussing solar heating systems in this article, we talk about that in detail in this article: The pros and cons of solar heating

So let’s start from first principles. If you get a cold drink and a hot cup of tea and leave them both on the table for an hour what happens? The cold drink gets warm and the hot drink gets cold. The liquid warms up or cools down to the ambient temperature surrounding it. It is exactly the same with your pool. The only difference is your pool sits there day and night  so whilst it may warm up some in the day it will cool down at night. So if you do nothing the water will reach the average day/night temperature for the time of year. In a typical british summer that is about 17C (63F), not especially warm.

First things first

The first thing you should do it buy a solar cover. Even the cheapest type will help but a good quality 400 micron solar cover will help the sunshine to warm water and also help keep the heat in during the colder nights. Using a solar cover should add at least 2C maybe up to 6C to the temperature. That will bring it up to about 19 to 23C (66 to 73C). 23C is not bad, on a really warm day most people would swim in 23C.

If the solar cover does not warm it enough for you then the next stage involves forking out for heater of some sort. There is a big barrier that affects your choice and that is the fact that from a 13amp plug socket in the wall you can only run a 3kw appliance.  3kw heaters are a very popular choice for that reason – you do not need an electrician to wire it in. You plug them in and connect them up and away you go. This is great but unless your pool is 10ft round or smaller you will not get the pool very warm. A 3kw heater will be OK on a 12ft pool but don’t expect anything over 25 or 26C in normal summers. Intex make a cheap 2kw heater. At £132.00 it is good value but it is not hi-tech, it has no thermostat but it will warm up a small pool. Elecro’s 3kw Nano heater at £265.00 is a much better piece of kit.

If 3kw is not enough to heat your pool, i.e. your pool is bigger than 12ft round then you have two main choices. If you are happy to get an electrician in then get a 6kw or a 9kw direct electric heater. Elecro are by far the best manufacturer of these heaters. 9kw will heat a pool up to 18ft round. Bear in mind that when running a 9kw heater and assuming day rate electricity of 13p per unit it will cost £1.17 per hour to run. They typically need to run for 4 to 6 hours per day to maintain the temperature. In a 150 day season your lecky bill could be over £1,000.00. Every season. You will not save electricity by having a smaller heater, it will cost the same and just take longer to heat the pool.

The best heater you can get

Don’t fancy the idea of paying £5,000 in electricity over the next 5 years? Then a heat pump is what you need. An Ecowarm EW10 gives up to 9.5kw of heat, but it only draws 1.9kw in electricity. It can plug in to the wall socket, no need for an electrician. At 25p per hour to run your lecky bill for the season should be more like £250.00.  So what is the drawback? Well, the EW10 costs £1,200.00 to buy but with a saving of £750 per season it pays back after 1 year.
“£1,200 for a heater, the pool only cost £300!” I hear you say. Yes, that is quite right. Heating up a large volume of water is not a cheap and easy thing to do.

Further Reading: How much does it cost to heat a swimming pool?

Click the links below to see the products discussed in this article:

Intex 2kw heater

Ecowarm Heat Pumps

Circular Solar Covers

Elecro Nano 3kw Heater

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