How do swimming pool heat pumps work?

The basic principle of how a heat pump works is simple. Everything around us has a heat value, be it a high temperature value, like a cooker hotplate, or a low temperature value like a block of ice. The purpose of a heat pump is to absorb heat in one place where it is plentiful, the air, and then enhance and increase it and then use that heat to heat your pool water.

How can the heat in the air be used though I hear you say? A simple illustration of this principle is your fridge. If you put a bottle of coke in the fridge, it gets colder. What’s actually happening is that the refrigerant that is being pumped through the coils in the back of the icebox within the fridge absorbs the heat in the air that the coke is giving off inside the fridge. In the case of a fridge (or freezer), that heat is dumped into the air from the evaporator at the back of the fridge.

That’s why it feels warm behind the fridge. Think freezer. It’s generally about -15 degrees inside, yet there is still heat collected from within and given off behind the fried- that’s how it’s staying so cold. Even at that low temperature, there is still heat inside and if that’s not removed, the freezer will warm and defrost. If you find that hard to believe, try turning off the freezer for a day or two and see how once the removal of the heat stops, the freezer defrosts! (see page ‘at what temperature will a heat pump work’

What about a swimming pool heat pump though? In the same way as the fridge doesn’t create heat but absorbed the heat from the can of coke, the swimming pool heat pump does not create heat, it simply captures free heat from the air and puts it into the refrigerant, enhancing it by compression and other techniques so that it is hot enough to heat the pool water passing it in a heat exchanger. Once it gives off its heat, the cooled refrigerant starts the whole cycle again.

The Nerdy Stuff

Calorex ProPac heat pumps are specifically designed for heating swimming pools. They are recognised as the most efficient way to heat a pool. Using one will result in energy savings of up to 47%, reducing both your energy costs and also as they provide 60% carbon emission savings when compared with fossil fuels.

What’s actually happening with the unit is using free heat from the air to give you up to 5.5 units of heat for every 1 unit paid for! But how does it do that? When its running a super quiet Owlet fan that draws huge amounts of air through the unit. The air passes though something that looks like a radiator, but that in reality is an evaporator that contains the refrigerant. This refrigerant absorbs the heat from the air passing it and the air that comes out the other side of the unit is freezing cold, with most of its heat removed! The heated gas is still at a fairly low temperature, but this gas then is pumped round the sealed circuit into a silently operating rotary scroll compressor like the one in your fridge and freezer The low temperature gas is compressed and this enhances the heat where it becomes heated to 45-55 degrees. The heated gas is then pumped round a heat exchanger, which is a container that has the hot refrigerant running through a coiled pipe within it and your pool water circulating past it. The heated gas transfers it heat into the cooler pool water. This happens continuously while the unit is running and this heats the pool.

This process provides a highly efficient, extremely economical and environmentally friendly system for heating your swimming pool.

Why Use A Carolex ProPac Heat Pump?

Calorex ProPac Heat Pumps are specifically designed for swimming pool heating. Heat pumps are recognised as the most sustainable way to dynamically heat swimming pool water and with a Calorex ProPac heat pump you will save both on energy and in operating costs!

Heat pumps simply use the free and natural energy in the air and transfer it efficiently to pool water heating, whilst respecting the environment. By careful design, a Calorex ProPac heat pump is capable of providing your pool with up to five and a half units of absorbed heat for every one unit paid for.

Advantages of a Heat Pump

• Substantial running cost savings (approximately 400% against electric heating) over extended summer season
• Up to 47% operating cost saving against fossil fuel boilers
• Up to 60% carbon saving against fossil fuel boilers
• Easy to retrofit to an existing pool system
• Minimal maintenance
• No fuels or fuel storage tanks

Key Features of the ProPac Heat Pump

• Designed, engineered and built in the UK for the UK climate
• Owlett Fans – super quiet
• Intelligent electronic defrost improves early and late season performance (X Models)
• High flow Titanium Heat Exchanger
• Two digital thermostat positions available
• Pool pump synchronisation control to maximise efficiency
• Leading brand rotary or scroll compressors
• 10 year anti-corrosion warranty on heat pump casing
• ProPac units comply with size requirements for permitted development rights (models 8-22kW)
• Fully supported by a nationwide network of Calorex engineers
• 3 year on site parts and labour warranty (models 8-22kW)

The Pro-Pac ‘X’ Range comes complete with an advanced hot gas defrost facility specifically designed for the UK’s changing climate. They can be placed discreetly in the pool area or sited in a plant room. They are quiet, ecologically friendly and economic to run. They come with titanium heat exchangers which are compatible with all types of water treatment. These models are elegant and simple to use. Just set the digital thermostat to ensure fully automatic operation throughout the summer season.

The Pro-Pac ‘Y’ Range models are fitted with reverse cycle defrost and will operate in air temperatures as low as -15OC, therefore they are suitable for all season use and indoor swimming pools.

The Pro-Pac Commercial Range are specifically designed to satisfy the needs of larger pools or those with a high level of activity, such as the leisure industry. Strong and reliable, the Pro-Pac Commercial Range includes five models up to 120kW output and are available in summer and reverse cycle all year round models. Pro-Pac units are easy to use and come with titanium heat exchangers, a flow switch, digital thermostat and vertical ventilation as standard.