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    Daikin air to air heat pump indoor unit installed in a modern living room

    Air to air heat pumps, installed across Surrey, Berkshire and west London

    An air to air heat pump is the modern name for a fixed air conditioning system. One outdoor unit, one or more indoor units, and it heats your home in winter and cools it in summer. It moves heat rather than making it, so it delivers several units of heat for every unit of electricity it uses. We design, install and look after them, and every engineer who comes to your home is F-Gas registered.

    What an air to air heat pump actually is

    If you have seen a wall-mounted air conditioning unit in a bedroom or a home office, you have seen an air to air heat pump. The outdoor unit gathers heat from the air, a compressor raises it to a useful temperature, and the indoor unit blows warm air into the room. Reverse the process and the same system takes heat out of the room and puts it outside. That is cooling.

    It is called "air to air" because it takes heat from the outside air and delivers it as warm air indoors. The other kind, "air to water", heats radiators and hot water instead. That is a different product, usually fitted by heating engineers. We do the air to air kind.

    Who it suits

    It suits a room or a floor that is hard to keep comfortable. A loft conversion that bakes in July and freezes in January. A home office you use all day. A conservatory or garden room you would like to use all year. A bedroom where you want cool air at night in summer and quiet, quick heat in the morning in winter.

    It also suits whole homes, particularly homes with no gas supply, homes with electric heating that costs too much to run, and new builds and renovations where the wiring and pipework can be planned in from the start. If you are an architect or a developer, we can work from your drawings.

    What it does not do is heat your radiators or your hot water. If that is what you need, you need an air to water heat pump, and we will say so.

    Heating in winter

    Yes, it works in a British winter. A modern unit keeps heating well below freezing. Efficiency drops a little on the coldest days because there is less heat in the air to gather, but it keeps running. Every unit we fit is rated for the temperatures this country actually reaches. [MINIMUM OPERATING TEMPERATURE OF THE UNITS HTC FITS — from the spec sheet]

    The figure to look at is the SCOP on the energy label. It tells you how many units of heat you get across a heating season for each unit of electricity. We will show you the figure for the exact model we quote, not a brochure average. There is more on running costs in our winter heating guide.

    Cooling in summer

    The same system cools. Set the temperature, and it holds it. A properly sized unit cools a room in minutes and then runs quietly to keep it there. If you have ever put a portable unit in a bedroom and listened to it all night, a fixed system is a different experience.

    What it costs

    Every home is different, so we quote after a survey. As a guide, this is what moves the price: how many rooms, how far the pipe runs, whether the electrics need upgrading, and where the outdoor unit can go. [HTC PRICE RANGE — single room / multi-room, to be confirmed by Harry]

    SystemTypical use
    Single splitone indoor unit, one outdoor unit, one room
    Multi splitup to five indoor units off one outdoor unit, several rooms
    Ductedhidden in the ceiling or loft, whole floor or whole home, nothing on the walls

    [VAT LINE — to be added once HTC's accountant has confirmed HTC's position in writing]

    The £2,500 government grant for air to air heat pumps is now published under the Boiler Upgrade Scheme, but it cannot be claimed yet because the installer approval route has not opened. We are following it closely. Read what is and isn't confirmed in our grant guide. Full price detail is on our cost page.

    How the installation works

    First, a survey. We look at the rooms, the walls, the loft and where the outdoor unit can sit, and we ask how you use the space. Then a fixed written quote, with the exact models named. On the day, a typical single-room installation is done in [TYPICAL INSTALL TIME — Harry to confirm]. We fit the units, run the pipework and the power supply, pressure-test and commission the system, and show you how to use it before we leave.

    All our engineers are F-Gas registered (registration 2004080), which the law requires for anyone handling refrigerant. We are Constructionline Gold, SMAS Worksafe and Acclaim accredited, and our engineers are City & Guilds qualified.

    The brands we fit

    We install Daikin, Mitsubishi Electric and Samsung systems. We choose the model for the room, not the other way round, and we will tell you why we have recommended what we have. Manufacturer warranties are [WARRANTY LENGTHS BY BRAND — Harry to confirm] and our workmanship is guaranteed for [WORKMANSHIP GUARANTEE — Harry to confirm].

    Where we work

    We are based in Lightwater, Surrey. For homes, we cover Surrey, Berkshire and west London — Woking, Guildford, Camberley, Farnham, Bracknell, Windsor, Weybridge, Kingston and the areas around them. For commercial work we cover London and the Home Counties. See all the areas we cover.

    What our customers say

    5.0 from 50 reviews on Google and 10 out of 10 from 66 reviews on Checkatrade.

    [PULL TWO REAL REVIEWS FROM THE APPROVED REVIEW LIST — do not invent]

    Questions people ask us

    Yes, in practice. A fixed air conditioning system that heats as well as cools is an air to air heat pump. The name has changed because the way people use it has changed. Most homes now buy it for heating and cooling, not cooling alone.

    Yes. It keeps heating well below freezing. On the very coldest days it briefly pauses now and then to defrost the outdoor unit, which is automatic. The heating load is checked at survey so the unit is sized for January, not just August.

    For a room or a home that is hard to heat or cool, usually yes. You get heating that costs less to run than a plug-in electric heater and cooling in the same unit. Whether it is worth it for you depends on how you use the space and what you heat with now, which is what the survey is for.

    Neither, normally. Air to air heat pumps are installed by air conditioning and refrigeration engineers, because the system contains refrigerant and the law requires an F-Gas registered engineer to handle it. That is what we are.

    Often not for a house, but the rules depend on where the outdoor unit goes, and flats, listed buildings and conservation areas are different. We check this for you at survey and tell you before you commit.

    On a low setting a modern indoor unit is typically quieter than a fridge. The outdoor unit makes a low hum. We site it away from bedroom windows and neighbours' boundaries, and we will tell you the sound rating of the exact model quoted.

    Not really. Systems sold as "no outdoor unit" exist but they are rare, expensive and usually less efficient. The honest answer is usually a well-placed outdoor unit, or a ducted system where nothing is visible indoors. We will show you the options at survey.

    No. That needs an air to water heat pump, which is a different product. If that is what you need, we will tell you.

    Book a free survey

    Tell us about the room or the home, and we will come and look. Fixed written quote, no pressure.

    HT Cooling Ltd

    Established air conditioning, refrigeration and HVAC contractors serving commercial, industrial and domestic clients across London and the Home Counties.

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    Office: Bourne Holdings, Broadway Road, Lightwater, Surrey GU18 5SH

    Registered in England and Wales. Company No. 13378090. VAT No. 382854660. Registered office: 7b Curley Hill Road, Lightwater, Surrey GU18 5YG.

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