Can I Add Cooling to My Existing Heat Pump? (UK Guide)

In many cases, yes, and it can be much easier than you might think.

Many air source heat pumps already have the ability to provide cooling. The problem is that most UK systems were installed purely for heating, so the cooling function was never set up or commissioned in the first place. It's often sitting there unused, built into a unit you've already paid for.

At UK Heat Pump Help, we've been testing heat pump cooling on real heating systems, including using existing underfloor heating, and we've found something genuinely useful for UK homes.

We've Tested Underfloor Cooling at 18°C

We've successfully run underfloor heating systems in cooling mode using a minimum water temperature of around 18°C. We're not trying to turn your floor into an ice rink. The aim is much simpler: take the edge off the heat.

Underfloor cooling isn't air conditioning. You shouldn't expect to walk into a room and feel a blast of cold air. Instead, the cooler floor gradually absorbs heat from the room and helps stop the property becoming as uncomfortable during hot weather. For a lot of UK homes, that's exactly what's actually needed, not a full air conditioning system, just enough to take the worst of a heatwave off the table. Our guide on whether your heat pump can cool your home covers how this compares to active air conditioning in more detail if you want the fuller picture before deciding.

Your Heat Pump May Already Be Capable of Doing It

Many modern heat pumps are capable of reversible operation, producing cooler water in summer as well as hot water for heating in winter. But that doesn't mean you should simply find the cooling setting on the controller and switch it on. Before anything gets activated, we need to check:

• Whether your particular heat pump model actually supports cooling mode

• Your existing controls, and whether they're capable of managing the switch between heating and cooling

• Your underfloor heating or other emitters, and whether they're suitable for running in cooling mode

• Pipework and insulation, since uninsulated pipework can create condensation problems once it's carrying cold water

• Wiring requirements, since enabling cooling sometimes needs additional wiring that wasn't part of the original heating-only installation

• How the system changes between heating and cooling, and whether that switch happens automatically or needs manual input

• Condensation risk, which is one of the most important things to get right and is genuinely serious enough that we've written a full guide on whether you need a dew point sensor for heat pump cooling

• Appropriate cooling temperatures for your specific property and emitters, rather than a generic setpoint that ignores how your home actually holds heat

Once we understand the existing installation properly, the modifications needed can sometimes be surprisingly straightforward, and in other cases genuinely aren't worth pursuing. Both outcomes are useful to know before you spend anything.

What If I Have Radiators?

Standard radiators generally aren't what we'd recommend for cooling. Running cold water through a radiator designed for heating tends to create condensation problems and delivers underwhelming cooling for the risk involved.

If you have underfloor heating downstairs but radiators upstairs, though, that doesn't necessarily stop you. There are several options worth considering. You could use the underfloor heating for gentle background cooling downstairs and potentially install fan coil units in bedrooms or other rooms where you want more noticeable cooling. Fan coils can provide much stronger cooling than underfloor circuits and can be particularly useful in bedrooms, loft conversions and south-facing rooms that struggle most in summer.

We Can Design the Conversion for You

This is where our Heat Pump Cooling Assessment comes in. We look at the system you've already got and work out the most practical way of adding cooling to it, rather than assuming a one-size-fits-all approach. We'll tell you:

• What your existing heat pump can actually do, based on its specific make and model rather than general assumptions

• Which parts of the house could realistically be cooled, and which probably can't without further work

• Whether your existing underfloor heating can be used for cooling as it stands

• What controls or wiring changes are required to make cooling mode work safely

• Whether fan coils would make sense for any particular rooms

• What pipework or insulation changes may be needed before cooling is switched on

• How we'd recommend setting and controlling the system once everything's in place

The idea isn't to sell you a completely new cooling system. It's to make the best possible use of the equipment you've already paid for, and to be honest with you if that equipment genuinely isn't suited to the job.

Already Have a Plumber or Electrician? That's Absolutely Fine

You don't necessarily need us to carry out the physical work. Once we've designed what needs doing, your own plumber or electrician can complete the modifications. We'll provide the information they need and can be available for technical support while they're on site, so if your electrician has a wiring question or your plumber isn't sure how we want something configured, they can speak to us directly rather than guessing. That means you can use tradespeople you already know and trust while still having specialist heat pump support behind them.

In Essex, Norfolk or Suffolk?

If you're in Essex, Norfolk or Suffolk, we may also be able to provide a price to complete the physical conversion for you directly. We'll assess the system first, explain exactly what's involved, and then give you the choice: use us to complete it, or take our design and use your own tradespeople instead. There's no obligation either way.

Don't Buy Air Conditioning Until You've Checked What Your Heat Pump Can Already Do

If you've already got a reversible heat pump, you may already own the most expensive part of a cooling system without realising it. Before spending thousands installing separate air conditioning throughout the house, it's worth finding out what your existing system is capable of first.

For some homes, gentle underfloor cooling is genuinely enough. For others, we might recommend combining it with fan coils in specific rooms that need more. And sometimes, honestly, we'll tell you conventional air conditioning makes more sense for what you're trying to achieve. The first step is simply finding out what's actually possible for your property before deciding.

Heat Pump Cooling Assessment

Already have a heat pump and want to know whether it can cool your home? We'll review your system, explain exactly what would be required, and give you a practical, honest route to getting it working, or tell you plainly if it isn't worth pursuing.

Essex, Norfolk or Suffolk? We can potentially quote for the physical work too. Elsewhere in the UK? Your own plumber and electrician can carry out the work using our instructions, with us available for technical support throughout.

Book a Heat Pump Cooling Assessment →