[{"data":1,"prerenderedAt":2020},["ShallowReactive",2],{"category-en-pool":3},{"pages":4,"i18nParams":2015},[5,904],{"id":6,"title":7,"author":8,"body":9,"dateModified":861,"datePublished":8,"description":862,"disableFeedback":863,"extension":864,"faq":865,"image":896,"meta":897,"navigation":898,"ogType":8,"path":899,"seo":900,"spatialCoverage":901,"stem":902,"translationKey":25,"__hash__":903},"en\u002Fen\u002Fpool\u002Fheat-pump-power-calculator.md","Pool heat pump power calculator",null,{"type":10,"value":11,"toc":846},"minimark",[12,24,28,31,36,46,69,76,81,84,215,221,224,228,231,238,245,266,270,273,284,302,312,337,343,350,354,402,407,410,512,517,521,547,550,556,574,589,593,596,653,662,676,686,690,693,723,726,730,737,740,747,751,754],[13,14,15,19,20,23],"p",{},[16,17,18],"strong",{},"Last updated: 5 September 2026"," · ",[16,21,22],{},"Private residential pools in France"," — climate zones H1–H3",[25,26],"pool-heat-pump-calculator",{":heading-level":27},"2",[29,30],"hr",{},[32,33,35],"h1",{"id":34},"what-size-heat-pump-does-your-pool-need","What size heat pump does your pool need?",[13,37,38,41,42,45],{},[16,39,40],{},"Who this is for:"," this calculator sizes the heat pump for a ",[16,43,44],{},"private residential\npool in France"," — in-ground or above-ground, up to 100 m³, heated over an April-to-\nSeptember season. The H1\u002FH2\u002FH3 climate zones and the tariffs quoted are French. It\ndoes not cover public, hotel or municipal pools, whose sizing and regulations differ.\nIf your pool is outside France, select your climate zone manually in step 3.",[13,47,48,49,52,53,56,57,60,61,64,65,68],{},"The rule French installers use fits on one line: ",[16,50,51],{},"the power in kW is roughly your pool's\nvolume in m³ times a climate coefficient"," — about ",[16,54,55],{},"0.18 in a cold zone (H1)",", ",[16,58,59],{},"0.15 in\na temperate one (H2)"," and ",[16,62,63],{},"0.12 on the Mediterranean coast (H3)",". So a 50 m³ pool in a\ntemperate climate needs around 7.5 kW, plus a margin of about 25 % for heating up: a range\nof ",[16,66,67],{},"7.5 to 11.5 kW"," depending on the region.",[13,70,71,72,75],{},"That starting point is then corrected for whatever makes your pool lose or keep heat: an\nuncovered pool needs about 30 % more, an enclosure up to 40 % less, and aiming for 28 °C\ninstead of 26 °C adds 12 %. The calculator below applies every one of those factors from\nfive questions and shows its working. The result is accurate to about ",[16,73,74],{},"±15 %"," — the same\nspread you would get between two professional quotes.",[77,78,80],"h2",{"id":79},"recommended-power-by-pool-volume","Recommended power by pool volume",[13,82,83],{},"In-ground pool, covered most of the time, in the open air, water at 26 °C, standard April-\nto-September season. Each range runs from the bare minimum to the 25 % margin.",[85,86,87,106],"table",{},[88,89,90],"thead",{},[91,92,93,97,100,103],"tr",{},[94,95,96],"th",{},"Pool volume",[94,98,99],{},"Zone H1 (cold)",[94,101,102],{},"Zone H2 (temperate)",[94,104,105],{},"Zone H3 (Mediterranean)",[107,108,109,124,139,155,170,184,200],"tbody",{},[91,110,111,117,120,122],{},[112,113,114],"td",{},[16,115,116],{},"20 m³",[112,118,119],{},"3.5 – 4.5 kW",[112,121,119],{},[112,123,119],{},[91,125,126,131,134,137],{},[112,127,128],{},[16,129,130],{},"30 m³",[112,132,133],{},"5.5 – 6.5 kW",[112,135,136],{},"4.5 – 5.5 kW",[112,138,119],{},[91,140,141,146,149,152],{},[112,142,143],{},[16,144,145],{},"40 m³",[112,147,148],{},"7.0 – 9.0 kW",[112,150,151],{},"6.0 – 7.5 kW",[112,153,154],{},"5.0 – 6.0 kW",[91,156,157,162,165,168],{},[112,158,159],{},[16,160,161],{},"50 m³",[112,163,164],{},"9.0 – 11.5 kW",[112,166,167],{},"7.5 – 9.5 kW",[112,169,151],{},[91,171,172,177,180,182],{},[112,173,174],{},[16,175,176],{},"60 m³",[112,178,179],{},"11.0 – 13.5 kW",[112,181,164],{},[112,183,148],{},[91,185,186,191,194,197],{},[112,187,188],{},[16,189,190],{},"80 m³",[112,192,193],{},"14.5 – 18.0 kW",[112,195,196],{},"12.0 – 15.0 kW",[112,198,199],{},"9.5 – 12.0 kW",[91,201,202,207,210,213],{},[112,203,204],{},[16,205,206],{},"100 m³",[112,208,209],{},"18.0 – 22.5 kW",[112,211,212],{},"15.0 – 19.0 kW",[112,214,196],{},[13,216,217],{},[218,219,220],"em",{},"Without a cover, add about 30 % to these values. Under an enclosure, take 15 to 40 % off\ndepending on the type. The calculator makes those adjustments for you.",[222,223],"article-toc",{},[77,225,227],{"id":226},"how-this-calculator-works","How this calculator works",[13,229,230],{},"This calculator gives you an instant, personalised estimate of the power your pool's heat\npump needs, with every step shown so you can check it yourself.",[13,232,233,234,237],{},"We start from how much water your pool holds, multiply it by a ",[16,235,236],{},"climate number"," for your\nregion, then nudge that up or down for the things that make a pool lose or keep heat.",[13,239,240,241,244],{},"The answer is a ",[16,242,243],{},"power range"," rather than a single figure: any pump inside it will heat\nyour pool well, and a bigger one simply heats it a little faster. Use it as a confident\nstarting point to compare models and quotes — it complements, rather than replaces, an\ninstaller's on-site survey.",[13,246,247,250,251,254,255,258,259,254,262,265],{},[16,248,249],{},"Two quick terms."," ",[218,252,253],{},"kW"," is ",[16,256,257],{},"power"," — how fast the pump delivers heat, and the\nnumber this tool gives you. ",[218,260,261],{},"kWh",[16,263,264],{},"energy"," — power used over time, i.e. what shows\nup on your electricity bill.",[77,267,269],{"id":268},"the-formula-behind-the-result","The formula behind the result",[13,271,272],{},"Here is the exact calculation — nothing is hidden:",[274,275,280],"pre",{"className":276,"code":278,"language":279},[277],"language-text","rawPower = volume\n         × climateCoeff[zone]     \u002F\u002F 0.18 \u002F 0.15 \u002F 0.12   ← the core\n         × coverFactor[cover]     \u002F\u002F is it covered?\n         × enclosureFactor[abri]  \u002F\u002F is it under a shelter?\n         × typeFactor[poolType]   \u002F\u002F in-ground or above-ground?\n         × tempFactor[targetTemp] \u002F\u002F how warm you want the water\n         × windFactor[wind]       \u002F\u002F how exposed it is\n         × seasonFactor[season]   \u002F\u002F summer \u002F standard \u002F year-round\n\npower = max(3.5, rawPower)         \u002F\u002F never below the smallest real pump\n","text",[281,282,278],"code",{"__ignoreMap":283},"",[13,285,286,287,290,291,294,295,298,299,301],{},"The square-bracket notation just means \"pick the value for your case\":\n",[281,288,289],{},"climateCoeff[zone]"," is the climate number for ",[218,292,293],{},"your"," zone, ",[281,296,297],{},"coverFactor[cover]"," is the\nfactor for ",[218,300,293],{}," cover, and so on.",[13,303,304,307,308,311],{},[16,305,306],{},"The core"," is the first line: ",[281,309,310],{},"volume × climateCoeff[zone]",". This is the standard\nvolume-based sizing method used by installers, and on its own it already lands within about\n10–15 % of what an installer would quote [1][2]. A bigger pool, or a colder climate\nzone, means more power — nothing more complicated than that.",[13,313,314,317,318,321,322,325,326,329,330,325,333,336],{},[16,315,316],{},"The adjustments"," are everything that follows. Each one is a simple multiplier:\nit equals ",[16,319,320],{},"1.0"," for a \"typical\" pool, sits ",[16,323,324],{},"above 1.0"," when it ",[218,327,328],{},"raises"," the power\nneeded, and ",[16,331,332],{},"below 1.0",[218,334,335],{},"lowers"," it.",[13,338,339,340,342],{},"They exist because no two pools lose heat the same way — a covered, sheltered pool in mild\nair behaves very differently from an exposed, uncovered one. By capturing the real heat\ndrivers (cover, shelter, exposure, target temperature, pool type), the adjustments turn a\ngeneric estimate into one that fits ",[218,341,293],{}," pool. That is what makes the recommended range\ntight and realistic instead of a one-size-fits-all guess.",[13,344,345,346,349],{},"Finally, ",[281,347,348],{},"max(3.5, …)"," simply means we never recommend a pump smaller than the\nsmallest model that actually exists.",[77,351,353],{"id":352},"the-factors-in-plain-language","The factors, in plain language",[355,356,357,364,370,376,386,392],"ul",{},[358,359,360,363],"li",{},[16,361,362],{},"How much water (volume)."," More water means more to heat, so this is the starting\npoint — that is why we ask for length, width and depth.",[358,365,366,369],{},[16,367,368],{},"Where you live (climate)."," Colder regions lose heat faster and need more power.\nYou just enter your postal code and we convert it into France's official climate\nzone [3], so you never have to guess.",[358,371,372,375],{},[16,373,374],{},"A cover."," The single biggest lever: evaporation is a pool's number-one source of\nheat loss, so a cover dramatically cuts the power you need.",[358,377,378,381,382,385],{},[16,379,380],{},"Shelter and wind."," An enclosure (a pool shelter or \"abri\") traps heat and lowers\nthe power needed; an exposed, windy spot speeds up evaporation and raises it — and a\n",[218,383,384],{},"very"," exposed spot (seaside, plateau, open plain) raises it more.",[358,387,388,391],{},[16,389,390],{},"Your target temperature."," Every extra degree costs power — that is why aiming for\n28 °C needs more than a comfortable 26 °C.",[358,393,394,397,398,401],{},[16,395,396],{},"Your heating period (season)."," Heating only in summer means mild air and lower\npower; stretching the season into colder air needs more power ",[218,399,400],{},"and"," costs more to run\n(the pump also loses efficiency as the air cools). Year-round use in cold air assumes\na pool enclosure — without one, a standard air\u002Fwater pump can't keep up.",[403,404,406],"h3",{"id":405},"at-a-glance-what-raises-or-lowers-your-power","At a glance: what raises or lowers your power",[13,408,409],{},"Starting from a \"typical\" pool (covered most of the time, in-ground, open air, 26 °C),\neach choice moves the power up or down:",[85,411,412,422],{},[88,413,414],{},[91,415,416,419],{},[94,417,418],{},"Your situation",[94,420,421],{},"Effect on power",[107,423,424,434,444,452,462,472,482,492,502],{},[91,425,426,429],{},[112,427,428],{},"No cover",[112,430,431],{},[16,432,433],{},"+30 %",[91,435,436,439],{},[112,437,438],{},"Cover at night only",[112,440,441],{},[16,442,443],{},"+15 %",[91,445,446,449],{},[112,447,448],{},"Cover most of the time",[112,450,451],{},"reference (no change)",[91,453,454,457],{},[112,455,456],{},"Roller shutter \u002F isothermic cover",[112,458,459],{},[16,460,461],{},"−8 %",[91,463,464,467],{},[112,465,466],{},"Shelter \u002F enclosure: low \"abri\" → high \"abri\" → indoor",[112,468,469],{},[16,470,471],{},"−15 % → −30 % → −40 %",[91,473,474,477],{},[112,475,476],{},"Above-ground (vs in-ground)",[112,478,479],{},[16,480,481],{},"+10 %",[91,483,484,487],{},[112,485,486],{},"Warmer water, 28 °C \u002F 30 °C",[112,488,489],{},[16,490,491],{},"+12 % \u002F +25 %",[91,493,494,497],{},[112,495,496],{},"Sheltered \u002F exposed \u002F very exposed spot",[112,498,499],{},[16,500,501],{},"−8 % \u002F +10 % \u002F +20 %",[91,503,504,507],{},[112,505,506],{},"Heating period: summer \u002F standard \u002F year-round",[112,508,509],{},[16,510,511],{},"−15 % \u002F reference \u002F +40 %",[13,513,514],{},[218,515,516],{},"These percentages are our own calibrated estimates (see the references note at the\nend); each is \"no change\" for the typical pool above.",[77,518,520],{"id":519},"a-worked-example-you-can-try","A worked example you can try",[522,523,524],"blockquote",{},[13,525,526,527,530,531,534,535,538,539,542,543,546],{},"Choose the ",[16,528,529],{},"\"8 × 4 m\" standard pool"," preset (an 8 × 4 × 1.5 m in-ground pool, which\nholds ",[16,532,533],{},"48 m³"," of water). Enter postal code ",[16,536,537],{},"33000 (Bordeaux — climate zone H2)",",\nleave the cover on ",[16,540,541],{},"\"at night\"",", and set the target temperature to ",[16,544,545],{},"28 °C",".",[13,548,549],{},"Dropped into the formula, that gives:",[274,551,554],{"className":552,"code":553,"language":279},[277],"rawPower = 48 (m³) × 0.15 (H2) × 1.15 (cover at night) × 1.0 (no shelter)\n                   × 1.0 (in-ground) × 1.12 (28 °C) × 1.0 (moderate wind)\n                   × 1.0 (standard season)\n         ≈ 9.27 kW   →   recommended range 9.5 – 11.5 kW\n",[281,555,553],{"__ignoreMap":283},[13,557,558,561,562,565,566,569,570,573],{},[16,559,560],{},"How does 9.27 kW become a 9.5 – 11.5 kW range?"," We round the target to the nearest\nhalf-kilowatt (→ ",[16,563,564],{},"9.5 kW",", the sensible minimum), then add up to ",[16,567,568],{},"+25 % headroom","\n(→ ",[16,571,572],{},"11.5 kW",") so the pump still heats comfortably in cooler weather. Any pump inside\nthat band suits this pool; a bigger one just warms the water faster.",[13,575,576,577,580,581,584,585,588],{},"Here the climate coefficient ",[16,578,579],{},"0.15"," is our calibrated value for temperate zone H2;\nit is consistent with the published per-region power charts [2] once you account for\nour covered-pool baseline (see the honesty note below). The cover (",[16,582,583],{},"1.15",") and\ntemperature (",[16,586,587],{},"1.12",") factors are likewise our own calibrated estimates.",[77,590,592],{"id":591},"where-our-numbers-come-from","Where our numbers come from",[13,594,595],{},"These are not made-up figures:",[355,597,598,624,631,638],{},[358,599,600,601,604,605,608,609,611,612,615,616,619,620,623],{},"The ",[16,602,603],{},"\"volume × climate\" method"," is the standard volume-based sizing method used by\ninstallers [1]. The specific coefficients (about ",[16,606,607],{},"0.18"," in cold zone H1, ",[16,610,579],{}," in\ntemperate H2, ",[16,613,614],{},"0.12"," on the Mediterranean H3) are ",[16,617,618],{},"our own calibrated values"," — no\nsingle guide publishes that exact set. They line up with independent per-region power\ncharts [2] once you allow for the fact that our coefficients assume a ",[218,621,622],{},"covered"," pool\n(uncover it, and our 0.12 \u002F 0.15 \u002F 0.18 rise to about 0.16 \u002F 0.20 \u002F 0.23 kW\u002Fm³, within\nthe published per-region range).",[358,625,626,627,630],{},"The climate zones are ",[16,628,629],{},"France's official RT2012 zones",", defined by Météo-France [3].",[358,632,633,634,637],{},"The heat-up time relies on a basic physics constant: it takes ",[16,635,636],{},"1.163 watt-hours to\nwarm one litre of water by one degree"," [1].",[358,639,640,641,644,645,648,649,652],{},"The running-cost estimate uses a typical electricity price [5] and a typical pump\nefficiency, or ",[16,642,643],{},"COP"," [4] — and you can adjust both in the advanced options. Your\n",[16,646,647],{},"heating period"," also moves the bill: a longer season means more hours running and\na lower average COP as the air cools, so a year-round setting costs noticeably more\nthan a summer one. (Cost figures current as of ",[16,650,651],{},"June 2026",", when the regulated base\nrate was about 0.19–0.20 €\u002FkWh; set your own tariff for an exact bill.)",[13,654,655,658,659,661],{},[16,656,657],{},"In all honesty:"," a few of the fine-tuning percentages (for example the exact effect\nof a cover, a shelter, wind exposure or the heating-period setting) are our own\ncalibrated estimates, and we say so openly. Overall the result is accurate to about\n",[16,660,74],{}," — the same spread you would get between two professional quotes. That is exactly\nwhy we give you a range and not a single \"perfect\" number.",[13,663,664,667,668,671,672,675],{},[16,665,666],{},"We test it."," The model is locked by an automated check against independent reference\ncases. For example, for an 80 m³ pool near Rennes our recommended ",[16,669,670],{},"17 – 21.5 kW","\nband brackets an independent professional configurator's ",[16,673,674],{},"17.4 kW","; small cold-climate\nand covered Mediterranean pools pass the same check, each landing within the tool's\n±15 % accuracy. If a coefficient ever changed, that test would flag it.",[13,677,678,681,682,685],{},[16,679,680],{},"Independent by design:"," the power is worked out first, purely from your pool's\ncharacteristics. Any product suggestions are matched to that result ",[218,683,684],{},"afterwards"," — the\nsizing is never influenced by what is for sale.",[77,687,689],{"id":688},"when-to-double-check-with-a-professional","When to double-check with a professional",[13,691,692],{},"This calculator is a reliable starting point for a typical outdoor home pool. Ask an\ninstaller for a tailored quote when:",[355,694,695,702,709,716],{},[358,696,697,698,701],{},"your pool is ",[16,699,700],{},"indoor"," — a very different heat-loss profile (the tool flags this\nresult as indicative);",[358,703,704,705,708],{},"you want to heat ",[16,706,707],{},"year-round in cold air"," — a standard air\u002Fwater pump drops out\nbelow about 5 °C, so this case really needs a pool enclosure (the tool flags it);",[358,710,711,712,715],{},"it is ",[16,713,714],{},"very large or an unusual shape"," — the model assumes a roughly rectangular\npool;",[358,717,718,719,722],{},"it sits in an ",[16,720,721],{},"extreme spot"," — high altitude, very exposed, or a strong local\nmicro-climate that a department-level climate zone cannot capture.",[13,724,725],{},"In those cases, use the range as a sanity check rather than the final word.",[77,727,729],{"id":728},"beware-the-power-printed-on-the-box","Beware the power printed on the box",[13,731,732,733,736],{},"The power you just calculated is ",[16,734,735],{},"useful"," power, at the 15 °C air \u002F 26 °C water\nreference condition. Manufacturers, however, usually advertise the figure measured at 26\nor 28 °C air — far more favourable conditions. Across the models we analysed the gap\ncommonly reaches 25 to 35 %: a pump sold as \"9 kW\" may deliver only 6.4 when you actually\nneed it.",[13,738,739],{},"So before you buy, read the spec sheet at the same air temperature the sizing was done at.",[741,742],"tool-cta",{"description":743,"label":744,"title":745,"to":746},"We compared 10 pool heat pumps on the market: here is the gap between the number on the box and the power measured at 15 °C air.","Read the analysis","Advertised power or real power?","\u002Fen\u002Fpool\u002Freal-vs-advertised-heat-pump-power",[77,748,750],{"id":749},"common-questions","Common questions",[752,753],"faq-section",{},[755,756,759,824],"content-section",{"icon":757,"title":758},"i-lucide-link","References",[760,761,762,775,786,806,817],"ol",{},[358,763,764,765,768,769],{},"Cash Piscines — ",[218,766,767],{},"Le guide ultime pour dimensionner votre pompe à chaleur de piscine","\n(the field-standard volume-based sizing method, its aggravating factors for cover and\nwind, and the 1.163 Wh\u002FL·°C water-heating constant — it uses a ΔT-based formula, not a\nper-zone coefficient table). ",[770,771,772],"a",{"href":772,"rel":773},"https:\u002F\u002Fwww.cash-piscines.com\u002Fconseils\u002Farticle\u002Fle-guide-ultime-pour-dimensionner-correctement-votre-pompe-a-chaleur-de-piscine",[774],"nofollow",[358,776,777,778,781,782],{},"Aqua Jardin — ",[218,779,780],{},"Pompe à chaleur piscine 50 m³ : quelle puissance ?"," (independent\nrecommended power by climate region, used to cross-check the coefficients).\n",[770,783,784],{"href":784,"rel":785},"https:\u002F\u002Faqua-jardin.fr\u002Fcomparatifs\u002Fpompe-chaleur-piscine-50m3\u002F",[774],[358,787,788,789,792,793,797,798,801,802],{},"Ministère de la Transition écologique — ",[218,790,791],{},"Répartition des départements par zone\nclimatique"," (the official government classification of French departments into climate\nzones H1\u002FH2\u002FH3, defined by Météo-France for the RT2012\u002FRE2020 regulations).\n",[770,794,795],{"href":795,"rel":796},"https:\u002F\u002Fwww.ecologie.gouv.fr\u002Fsites\u002Fdefault\u002Ffiles\u002Fdocuments\u002FLa%20r%C3%A9partition%20des%20d%C3%A9partements%20par%20zone%20climatique.pdf",[774],"\nPlain-language overview: Hellowatt — ",[218,799,800],{},"Zone climatique France : définition, carte et\nimpact",". ",[770,803,804],{"href":804,"rel":805},"https:\u002F\u002Fwww.hellowatt.fr\u002Frenovation\u002Fglobale\u002Fzone-climatique",[774],[358,807,808,809,812,813],{},"Guide-piscine.fr — ",[218,810,811],{},"Qu'est-ce que le COP d'une pompe à chaleur de piscine ?"," (a pool\nheat pump's coefficient of performance: should not be below ~3.5, typically around 4).\n",[770,814,815],{"href":815,"rel":816},"https:\u002F\u002Fwww.guide-piscine.fr\u002Fpompe-a-chaleur\u002Fqu-est-ce-que-le-cop-d-une-pompe-a-chaleur-de-piscine-5457_A",[774],[358,818,819,820],{},"Fournisseurs-Électricité \u002F EDF Tarif Bleu — regulated electricity price per kWh\n(Base option), used as the default running-cost rate.\n",[770,821,822],{"href":822,"rel":823},"https:\u002F\u002Fwww.fournisseurs-electricite.com\u002Ffournisseurs\u002Fedf\u002Ftarifs\u002Fbase",[774],[13,825,826,829,830,833,834,837,838,841,842,845],{},[218,827,828],{},"Note on the coefficients and factors:"," the volume × climate ",[16,831,832],{},"method"," is\nfield-standard [1], and our per-zone coefficients are ",[16,835,836],{},"consistent with"," published\nper-region power figures [2] once normalised for our covered-pool baseline. But the\nexact ",[281,839,840],{},"0.18 \u002F 0.15 \u002F 0.12"," triplet, and the fine-tuning cover, shelter, wind, per-degree\ntemperature and heating-period (season) factors, are ",[16,843,844],{},"calibrated in-house estimates"," —\nno single public source prints those exact values. We present them as engineering\nestimates, which is why the tool's output is a range accurate to roughly ±15 % rather than\na single guaranteed figure.",{"title":283,"searchDepth":847,"depth":847,"links":848},2,[849,850,851,852,856,857,858,859,860],{"id":79,"depth":847,"text":80},{"id":226,"depth":847,"text":227},{"id":268,"depth":847,"text":269},{"id":352,"depth":847,"text":353,"children":853},[854],{"id":405,"depth":855,"text":406},3,{"id":519,"depth":847,"text":520},{"id":591,"depth":847,"text":592},{"id":688,"depth":847,"text":689},{"id":728,"depth":847,"text":729},{"id":749,"depth":847,"text":750},"2026-09-05","What size heat pump does your pool need? Roughly 0.15 kW per m³ in a temperate climate. Free sizing in 5 questions, instant result.",false,"md",[866,869,872,875,878,881,884,887,890,893],{"q":867,"a":868},"What size heat pump do I need for a 50 m³ pool?","Around 7.5 to 9.5 kW in a temperate climate (French zone H2), 9 to 11.5 kW in a cold one (H1) and 6 to 7.5 kW on the Mediterranean coast (H3). Those ranges assume an in-ground pool, covered most of the time, in the open air and heated to 26 °C from April to September. Without a cover, add about 30 %.",{"q":870,"a":871},"What size heat pump do I need for an 8 × 4 m pool?","An 8 × 4 m pool at 1.5 m deep holds 48 m³ of water. In a temperate climate that gives a recommended range of 7 to 9 kW for a covered pool at 26 °C. Aim for the top of the range if the pool is uncovered, if you want 28 °C, or if the spot is windy.",{"q":873,"a":874},"Should I oversize my pool heat pump?","A margin of about 25 % above the target power is healthy: it speeds up the temperature rise and keeps performance up in cooler weather, when the pump loses efficiency. That is exactly why this calculator shows a range rather than a single figure — the bottom is the bare minimum, the top includes that margin. Beyond it you pay for a bigger unit without gaining much.",{"q":876,"a":877},"Does a cover really change the power needed?","Yes, it is the single biggest factor: evaporation is a pool's number-one source of heat loss. Going from an uncovered pool to one covered most of the time cuts the power needed by roughly 30 %, and cuts the running cost by about as much. A roller shutter or isothermic bubble cover does slightly better still.",{"q":879,"a":880},"How long does a heat pump take to warm up a pool?","Expect about a week for the very first heat-up of a 50 m³ pool going from 12 to 26 °C, with a correctly sized pump running during the filtration cycles (around 12 hours a day). After that, holding the temperature takes a fraction of the time. A more powerful pump shortens the first heat-up, not the holding.",{"q":882,"a":883},"How much does it cost to heat a pool with a heat pump?","For a 50 m³ pool in a temperate climate heated to 26 °C over a standard season, budget roughly €100 to €250 of electricity a year depending on whether it is covered, at 2026 regulated French rates. The cover, the target temperature and the length of the heating season matter far more to the bill than which pump model you buy.",{"q":885,"a":886},"What COP should I look for in a pool heat pump?","A COP (coefficient of performance) of about 4 is the norm for a pool heat pump, and it should not drop below 3.5. A COP of 4 means the pump delivers 4 kWh of heat for every 1 kWh of electricity it consumes. Watch out: COP is always quoted at a specific air temperature and falls as the air cools, so only compare COPs measured under the same conditions.",{"q":888,"a":889},"Does a pool heat pump work in winter?","A standard air-to-water heat pump drops out below roughly 5 °C of air temperature: its efficiency collapses and then it stops. Heating year-round therefore assumes a pool enclosure, which limits losses and keeps the air around the pool milder. Without one, a heat pump alone will not carry you through winter in most of France.",{"q":891,"a":892},"Why is a heat pump's advertised power not its real power?","Manufacturers usually quote the power measured at 26 or 28 °C air — ideal conditions you do not get at the start and end of the season. At 15 °C air, the reference condition used for sizing, the same machine often delivers 25 to 35 % less. Always compare pumps at the same air temperature before concluding that one model is more powerful than another.",{"q":894,"a":895},"Does an above-ground pool need more power than an in-ground one?","Yes, about 10 % more for the same volume: its walls sit in open air and lose heat, whereas the ground around an in-ground pool acts as insulation. On a small above-ground pool the gap stays modest in absolute terms, but it grows with volume.","\u002Fog\u002Fog-pool-heat-pump-calculator-en.png",{},true,"\u002Fen\u002Fpool\u002Fheat-pump-power-calculator",{"title":7,"description":862},"France","en\u002Fpool\u002Fheat-pump-power-calculator","UPvLK6nR-BAOLXrd8w43sOsgQp47W3flIl4YZ5FPLTU",{"id":905,"title":906,"author":907,"body":908,"dateModified":1986,"datePublished":1987,"description":1988,"disableFeedback":863,"extension":864,"faq":1989,"image":2008,"meta":2009,"navigation":898,"ogType":2010,"path":746,"seo":2011,"spatialCoverage":901,"stem":2012,"translationKey":2013,"__hash__":2014},"en\u002Fen\u002Fpool\u002Freal-vs-advertised-heat-pump-power.md","Pool heat pumps: 9 kW advertised, 6.4 kW delivered — it all hangs on one line of the spec sheet","Calculhouse",{"type":10,"value":909,"toc":1960},[910,913,918,921,940,943,945,949,956,959,964,967,971,978,989,998,1001,1008,1011,1066,1077,1084,1088,1092,1095,1110,1113,1117,1120,1125,1131,1135,1139,1142,1163,1169,1178,1181,1188,1192,1195,1212,1215,1219,1230,1244,1251,1255,1258,1261,1286,1290,1532,1539,1544,1548,1577,1588,1591,1596,1600,1606,1617,1627,1632,1636,1642,1654,1661,1664,1669,1672,1678,1687,1692,1696,1699,1729,1733,1736,1765,1771,1775,1778,1799,1802,1806,1809,1827,1832,1839,1842,1846,1855,1857,1859,1957],[32,911,906],{"id":912},"pool-heat-pumps-9-kw-advertised-64-kw-delivered-it-all-hangs-on-one-line-of-the-spec-sheet",[13,914,915],{},[218,916,917],{},"Last updated: 14 August 2026 — Calculhouse",[919,920],"pool-heat-pump-power-hero",{},[522,922,923],{},[13,924,925,250,928,931,932,935,936,939],{},[16,926,927],{},"In short.",[218,929,930],{},"(Private residential pools, in France.)"," A pool heat pump advertised as \"9 kW\" only delivers that figure in\nfavourable conditions (26 °C air). As soon as the air falls towards 15 °C, in spring or\nautumn, real power drops — by ",[16,933,934],{},"about 29 % on average"," across our survey of 10\nreferences (Poolex, Astralpool, GRE, Zodiac, Hayward). For an extended April-to-October\nseason in France, it is the ",[16,937,938],{},"power at 15 °C"," you should be reading, not the headline\nfigure. And two models are only comparable if they are quoted in the same test condition.",[13,941,942],{},"Comparing heat pumps for your pool and going by the kilowatt figure on the box? That is the\nnatural instinct — and it is also the surest way to get it wrong. Not because the number is\nfalse, but because it means nothing until you know the condition it was measured in. Here\nis how to read that number properly, once and for all.",[222,944],{},[77,946,948],{"id":947},"_1-the-trap-of-the-kw-figure","1. The trap of the kW figure",[13,950,951,952,955],{},"Plenty of pool owners pick their heat pump on a single number: \"5 kW\", \"7 kW\", \"9 kW\". It is\nsimple, it is reassuring, and it is incomplete. A pool heat pump does not have ",[218,953,954],{},"one"," power\nrating: it has several, and they move with the outside temperature, the water temperature\nand the humidity of the air.",[13,957,958],{},"So let us put the real question, the one that drives this whole article:",[522,960,961],{},[13,962,963],{},"Does a heat pump advertised at 9 kW really supply 9 kW when you need it most, in spring?",[13,965,966],{},"The short answer: often no — and sometimes yes. It all depends on the condition hidden\nbehind the figure. Learning to spot it is the only skill that really matters when choosing.",[77,968,970],{"id":969},"_2-why-doesnt-a-heat-pump-have-a-single-power-rating","2. Why doesn't a heat pump have a single power rating?",[13,972,973,974,977],{},"Before talking about what is printed, it helps to understand why the power moves. A heat\npump does not \"make\" heat: it ",[16,975,976],{},"takes heat from the outside air"," and moves it into the\npool water. Its performance therefore depends directly on what that air contains:",[355,979,980,983,986],{},[358,981,982],{},"warm air → plenty of available heat → high delivered power;",[358,984,985],{},"cool air → less heat → reduced delivered power;",[358,987,988],{},"humidity counts too: the damper the air, the more so-called latent heat it carries, and\nthe more the machine can recover.",[13,990,991],{},[992,993],"img",{"alt":994,"height":995,"src":996,"width":997},"A heat pump takes heat from the outside air and transfers it into the pool water",400,"\u002Fillustration-3-principe-pac-en.svg",820,[13,999,1000],{},"Hence the central point to take away:",[522,1002,1003],{},[13,1004,1005],{},[16,1006,1007],{},"A heat pump's power is a value measured under precise conditions, not a fixed property\nof the machine.",[13,1009,1010],{},"French spec sheets mostly use two reference conditions:",[85,1012,1013,1032],{},[88,1014,1015],{},[91,1016,1017,1020,1023,1026,1029],{},[94,1018,1019],{},"Condition",[94,1021,1022],{},"Air",[94,1024,1025],{},"Water",[94,1027,1028],{},"Humidity",[94,1030,1031],{},"Use it represents",[107,1033,1034,1050],{},[91,1035,1036,1039,1042,1044,1047],{},[112,1037,1038],{},"Favourable (usually advertised)",[112,1040,1041],{},"26 °C",[112,1043,1041],{},[112,1045,1046],{},"80 %",[112,1048,1049],{},"High summer",[91,1051,1052,1055,1058,1060,1063],{},[112,1053,1054],{},"NF-414 standard",[112,1056,1057],{},"15 °C",[112,1059,1041],{},[112,1061,1062],{},"70 %",[112,1064,1065],{},"Spring \u002F autumn, extended season",[13,1067,1068,1069,1072,1073,1076],{},"In practice, the same machine can show ",[16,1070,1071],{},"9 kW at 26 °C air"," and deliver only ",[16,1074,1075],{},"6.4 kW at\n15 °C air"," — same components, same unit, two different conditions. The number changes; the\nmachine does not.",[13,1078,1079],{},[992,1080],{"alt":1081,"height":1082,"src":1083,"width":997},"The same heat pump shows 9 kW at 26 °C but 6.4 kW at 15 °C",470,"\u002Fillustration-1-meme-pac-deux-conditions-en.svg",[77,1085,1087],{"id":1086},"_3-the-two-power-figures-an-owner-needs-to-know","3. The two power figures an owner needs to know",[403,1089,1091],{"id":1090},"the-shop-window-figure-favourable-condition-26-c","The \"shop window\" figure (favourable condition, ~26 °C)",[13,1093,1094],{},"This is the one you most often find in large type on sales pages. It is measured in warm\nconditions (air ≈ 26 °C, water ≈ 26 °C, 80 % humidity). To be fair to it:",[355,1096,1097,1104,1107],{},[358,1098,1099,1100,1103],{},"it represents the machine's ",[16,1101,1102],{},"maximum potential",";",[358,1105,1106],{},"it corresponds to a real, standardised test condition, not an invention;",[358,1108,1109],{},"and, inevitably, it produces the biggest number — so the most saleable one.",[13,1111,1112],{},"Its only flaw: it does not reflect the power actually available at the start or the end of\nthe season, when the air is cooler.",[403,1114,1116],{"id":1115},"the-power-at-15-c","The power at 15 °C",[13,1118,1119],{},"This is closer to real extended use at our latitudes: warming the pool back up after winter,\nspring mornings, the tail end of autumn.",[522,1121,1122],{},[13,1123,1124],{},"To size an outdoor pool heat pump in France for an extended season, the power around\n15 °C is the most useful piece of information.",[13,1126,1127,1130],{},[16,1128,1129],{},"An important nuance, worth remembering:"," some brands already publish their power at\n15 °C. So not everyone \"inflates\" their figure — more on that below.",[77,1132,1134],{"id":1133},"_4-what-this-difference-changes-in-practice","4. What this difference changes in practice",[403,1136,1138],{"id":1137},"power-heating-speed","Power = heating speed",[13,1140,1141],{},"Two ideas that often get confused:",[355,1143,1144,1154],{},[358,1145,1146,1149,1150,1153],{},[16,1147,1148],{},"Power (kW)"," = the ",[218,1151,1152],{},"rate"," at which you heat the water.",[358,1155,1156,1149,1159,1162],{},[16,1157,1158],{},"Energy needed (kWh)",[218,1160,1161],{},"total amount"," of heat you must supply to reach the\ntemperature you want.",[13,1164,1165,1166,546],{},"A rough order of magnitude, for a 50 m³ pool: it takes ",[16,1167,1168],{},"about 58 kWh to gain 1 °C",[522,1170,1171],{},[13,1172,1173,1174,1177],{},"Careful: those 58 kWh are a ",[16,1175,1176],{},"theoretical minimum, before losses",". In real conditions,\nevaporation, wind and night-time cooling raise the requirement noticeably. If you time it\nat home you will always find it takes a bit longer — that is normal.",[13,1179,1180],{},"For the same requirement, a pump delivering 7 kW heats faster than one delivering 5 kW.\nPower does not change how much heat you have to supply; it changes how long it takes.",[13,1182,1183],{},[992,1184],{"alt":1185,"height":1186,"src":1187,"width":997},"Power (heating speed, in kW) and energy (total heat required, in kWh) are two different things",420,"\u002Fillustration-2-puissance-vs-energie-en.svg",[403,1189,1191],{"id":1190},"a-pump-chosen-on-the-shop-window-figure-can-end-up-undersized","A pump chosen on the shop-window figure can end up undersized",[13,1193,1194],{},"Take a verified case, the Poolex Silverline On\u002FOff 7 kW:",[355,1196,1197,1203],{},[358,1198,1199,1202],{},[16,1200,1201],{},"advertised: 7 kW"," (Air 26 °C \u002F Water 26 °C \u002F 80 %);",[358,1204,1205,1208,1209,546],{},[16,1206,1207],{},"real at 15 °C: 4.7 kW",", i.e. ",[16,1210,1211],{},"−33 %",[13,1213,1214],{},"If you had picked that model counting on its 7 kW for spring use, you would discover:\nslower heating than expected, difficulty reaching the set temperature in the shoulder\nseason, and a compressor running longer to compensate.",[403,1216,1218],{"id":1217},"the-role-of-your-usage-period","The role of your usage period",[13,1220,1221,1222,1225,1226,1229],{},"Here is the point that puts everything in order: your usage period is not a ",[218,1223,1224],{},"consequence"," of\nsizing, it is the ",[16,1227,1228],{},"parameter that decides"," which power figure to look at.",[355,1231,1232,1238],{},[358,1233,1234,1237],{},[16,1235,1236],{},"July–August only:"," the air is warm, so the 26 °C condition already represents your\nreality. The shop-window figure is relevant, and there is no undersizing problem.",[358,1239,1240,1243],{},[16,1241,1242],{},"Extended April–October use:"," you have to reason on the power at 15 °C, otherwise the\nmachine struggles as soon as you step outside the height of summer.",[13,1245,1246,1247,1250],{},"In other words, it is not \"15 °C is always the right measure\". It is \"15 °C is the right\nmeasure ",[218,1248,1249],{},"if"," you want to extend the season\".",[77,1252,1254],{"id":1253},"_5-ten-real-references-analysed","5. Ten real references analysed",[13,1256,1257],{},"Enough principles: here are the figures taken from actual spec sheets.",[403,1259,1260],{"id":832},"Method",[355,1262,1263,1266,1269,1272,1279],{},[358,1264,1265],{},"10 representative references, drawn from a wider survey of 23 models.",[358,1267,1268],{},"Three brands to illustrate the trend (Poolex, Astralpool, GRE) and two as\ncounter-examples (Zodiac, Hayward).",[358,1270,1271],{},"Two technologies (On\u002FOff and Full Inverter), sizes from 7 to 20 kW.",[358,1273,1274,1275,1278],{},"Comparison ",[16,1276,1277],{},"at identical conditions",": Air 26 °C \u002F Water 26 °C \u002F 80 % against Air 15 °C \u002F\nWater 26 °C \u002F 70 %.",[358,1280,1281,1282,1285],{},"The wording is deliberately neutral: ",[16,1283,1284],{},"\"gap between advertised power and power at 15 °C\"",",\nnot \"overstatement\".",[403,1287,1289],{"id":1288},"the-10-references","The 10 references",[85,1291,1292,1317],{},[88,1293,1294],{},[91,1295,1296,1299,1302,1305,1308,1311,1314],{},[94,1297,1298],{},"#",[94,1300,1301],{},"Brand",[94,1303,1304],{},"Model",[94,1306,1307],{},"Advertised power",[94,1309,1310],{},"Advertised condition",[94,1312,1313],{},"Power at 15 °C",[94,1315,1316],{},"Gap",[107,1318,1319,1341,1360,1381,1401,1423,1443,1464,1483,1509],{},[91,1320,1321,1324,1327,1330,1333,1336,1339],{},[112,1322,1323],{},"1",[112,1325,1326],{},"Poolex",[112,1328,1329],{},"Silverline On\u002FOff 7 kW",[112,1331,1332],{},"7.0 kW",[112,1334,1335],{},"Air 26° \u002F Water 26° \u002F 80 %",[112,1337,1338],{},"4.7 kW",[112,1340,1211],{},[91,1342,1343,1345,1347,1350,1353,1355,1358],{},[112,1344,27],{},[112,1346,1326],{},[112,1348,1349],{},"Silverline On\u002FOff 15 kW",[112,1351,1352],{},"15.0 kW",[112,1354,1335],{},[112,1356,1357],{},"10.0 kW",[112,1359,1211],{},[91,1361,1362,1365,1367,1370,1373,1375,1378],{},[112,1363,1364],{},"3",[112,1366,1326],{},[112,1368,1369],{},"Silverline Fi 90 (Full Inverter)",[112,1371,1372],{},"9.2 kW",[112,1374,1335],{},[112,1376,1377],{},"6.4 kW",[112,1379,1380],{},"−30 %",[91,1382,1383,1386,1388,1391,1394,1396,1399],{},[112,1384,1385],{},"4",[112,1387,1326],{},[112,1389,1390],{},"Silverline Top 12 (Full Inverter)",[112,1392,1393],{},"12.6 kW",[112,1395,1335],{},[112,1397,1398],{},"8.9 kW",[112,1400,1380],{},[91,1402,1403,1406,1409,1412,1415,1417,1420],{},[112,1404,1405],{},"5",[112,1407,1408],{},"Astralpool",[112,1410,1411],{},"Eco Elyo-13 (Full Inverter)",[112,1413,1414],{},"13.0 kW",[112,1416,1335],{},[112,1418,1419],{},"9.0 kW",[112,1421,1422],{},"−31 %",[91,1424,1425,1428,1430,1433,1436,1438,1440],{},[112,1426,1427],{},"6",[112,1429,1408],{},[112,1431,1432],{},"Eco Elyo-20 (Full Inverter)",[112,1434,1435],{},"20.0 kW",[112,1437,1335],{},[112,1439,1352],{},[112,1441,1442],{},"−25 %",[91,1444,1445,1448,1451,1454,1456,1458,1461],{},[112,1446,1447],{},"7",[112,1449,1450],{},"GRE",[112,1452,1453],{},"HPGIC45 (Full Inverter)",[112,1455,1332],{},[112,1457,1335],{},[112,1459,1460],{},"5.5 kW",[112,1462,1463],{},"−21 %",[91,1465,1466,1469,1471,1474,1477,1479,1481],{},[112,1467,1468],{},"8",[112,1470,1450],{},[112,1472,1473],{},"HPGIC75 (Full Inverter)",[112,1475,1476],{},"12.0 kW",[112,1478,1335],{},[112,1480,1419],{},[112,1482,1442],{},[91,1484,1485,1488,1491,1494,1497,1503,1506],{},[112,1486,1487],{},"9",[112,1489,1490],{},"Zodiac",[112,1492,1493],{},"PX25 (Full Inverter)",[112,1495,1496],{},"5.5 → 24 kW",[112,1498,1499,1502],{},[16,1500,1501],{},"Air 15°"," \u002F Water 26° \u002F 70 %",[112,1504,1505],{},"already at 15 °C",[112,1507,1508],{},"≈ 0 %",[91,1510,1511,1514,1517,1520,1523,1528,1530],{},[112,1512,1513],{},"10",[112,1515,1516],{},"Hayward",[112,1518,1519],{},"EnergyLine Pro ENP5",[112,1521,1522],{},"14.8 kW",[112,1524,1525,1527],{},[16,1526,1501],{}," \u002F Water 24° *",[112,1529,1505],{},[112,1531,1508],{},[13,1533,1534,1535,1538],{},"* Hayward measures here at ",[16,1536,1537],{},"24 °C water"," (not 26 °C) — a slightly different condition,\nwhich we flag for the sake of rigour.",[13,1540,1541],{},[218,1542,1543],{},"Each row's number matches its source, listed in the \"Sources\" section at the end.",[403,1545,1547],{"id":1546},"reading-the-results","Reading the results",[355,1549,1550,1560,1567],{},[358,1551,1552,1553,1556,1557,546],{},"Across the 8 references advertised at 26 °C, the gap ranges from ",[16,1554,1555],{},"−21 % to −33 %",", with\nan ",[16,1558,1559],{},"average of about −29 %",[358,1561,1562,1563,1566],{},"Across all 23 models in the full survey: ",[16,1564,1565],{},"average −27.5 %",", median −26.6 %.",[358,1568,1569,1572,1573,1576],{},[16,1570,1571],{},"A nuance by technology:"," On\u002FOff models appear to lose more (≈ −33 %) than Full Inverter\nones (≈ −26 %). Treat that carefully: the difference comes mostly from ",[218,1574,1575],{},"how"," each\ntechnology is specified on the sheet (a modulation range for Inverter, a fixed point for\nOn\u002FOff) rather than from any obvious physical superiority of one over the other.",[522,1578,1579],{},[13,1580,1581,1584,1585,546],{},[16,1582,1583],{},"Figure to remember (Calculhouse survey, 10 references, July 2026):"," between the power\nadvertised at 26 °C and the real power at 15 °C, the average measured gap is\n",[16,1586,1587],{},"about −29 %",[13,1589,1590],{},"The example to keep in mind:",[522,1592,1593],{},[13,1594,1595],{},"A heat pump advertised at 15 kW may supply only around 10 kW in conditions close to 15 °C.",[77,1597,1599],{"id":1598},"_6-does-cop-follow-the-same-logic-yes","6. Does COP follow the same logic? (yes)",[13,1601,1602,1603,1605],{},"This does not only affect power. ",[16,1604,643],{}," (coefficient of performance = energy delivered ÷\nenergy consumed) is the second \"too good\" number on sales pages. Like power, it is measured\nin favourable conditions:",[355,1607,1608,1611],{},[358,1609,1610],{},"at 26 °C, spec sheets show spectacular COPs — up to 12 to 16 at peak on some Full\nInverter models;",[358,1612,1613,1614,546],{},"at 15 °C, the same unit falls back to between ",[16,1615,1616],{},"4.4 and 8",[13,1618,1619,1620,1623,1624,546],{},"A verified example, again on the Poolex Silverline On\u002FOff: COP quoted at ",[16,1621,1622],{},"6.15 at 26 °C",",\nbut ",[16,1625,1626],{},"4.4 to 4.6 at 15 °C",[522,1628,1629],{},[13,1630,1631],{},"When you read \"COP up to 16\", look for the condition. At 15 °C, a good COP is around 4\nto 6. That is already excellent — and it is the realistic figure to plan with.",[77,1633,1635],{"id":1634},"_7-do-all-brands-inflate-their-advertised-power","7. Do all brands inflate their advertised power?",[13,1637,1638,1639],{},"It would be unfair — and wrong — to conclude that \"every manufacturer inflates their\nfigures\". The dominant practice (Poolex, Astralpool, GRE and others) is indeed to advertise\npower at 26 °C. ",[16,1640,1641],{},"But it is not universal:",[355,1643,1644,1649],{},[358,1645,1646,1648],{},[16,1647,1490],{}," (PX25, Z250, Z300 ranges) publishes its power directly at Air 15 °C \u002F Water\n26 °C \u002F 70 %;",[358,1650,1651,1653],{},[16,1652,1516],{}," (EnergyLine Pro) also publishes at Air 15 °C, with NF-414 certification.",[13,1655,1656,1657,1660],{},"What they have in common: these brands claim ",[16,1658,1659],{},"NF PAC \u002F NF-414 certification",", which\nrequires communicating on the standard 15 °C condition.",[13,1662,1663],{},"Which raises the question every reader now has:",[522,1665,1666],{},[13,1667,1668],{},"\"If 15 °C is more honest, why doesn't everyone publish it?\"",[13,1670,1671],{},"The answer is simple: because 26 °C gives a bigger number, therefore a more saleable one,\nand nothing legally obliges a manufacturer to publish the 15 °C figure — unless it\nvoluntarily commits to a certification scheme.",[13,1673,1674,1675],{},"Hence ",[16,1676,1677],{},"the central lesson of this article:",[522,1679,1680],{},[13,1681,1682,1683,1686],{},"Two \"9 kW\" heat pumps are only comparable if they are quoted in the ",[16,1684,1685],{},"same condition",". A\n\"Poolex 9 kW\" (9 kW at 26 °C, so ≈ 6.4 kW at 15 °C) and a \"Zodiac 9 kW\" (9 kW at 15 °C)\nare simply not in the same class.",[741,1688],{"description":1689,"label":1690,"title":1691,"to":899},"Our calculator works directly on the 15 °C figure — the one that actually matters for an extended season.","Size the heat pump for my pool","Want to know what this means for your pool?",[77,1693,1695],{"id":1694},"_8-common-misconceptions-worth-correcting","8. Common misconceptions worth correcting",[13,1697,1698],{},"A quick memo to keep handy:",[355,1700,1701,1707,1713,1719],{},[358,1702,1703,1706],{},[16,1704,1705],{},"\"A 9 kW heat pump always produces 9 kW.\""," → No: power varies with the measurement\nconditions.",[358,1708,1709,1712],{},[16,1710,1711],{},"\"The bigger the number, the better the pump.\""," → Not necessarily: a big figure at\n26 °C can hide modest power at 15 °C.",[358,1714,1715,1718],{},[16,1716,1717],{},"\"Pool volume is enough to choose.\""," → No: region, target temperature, usage period,\ncover and exposure matter just as much.",[358,1720,1721,1724,1725,1728],{},[16,1722,1723],{},"\"The advertised figure is a lie.\""," → No: it is accurate ",[218,1726,1727],{},"within its condition",". The\nreal problem is comparing different conditions without noticing.",[77,1730,1732],{"id":1731},"_9-the-other-sizing-factors","9. The other sizing factors",[13,1734,1735],{},"So as not to reduce everything to power, bear in mind that the real requirement also depends\non:",[355,1737,1738,1743,1749,1759],{},[358,1739,1740,1742],{},[16,1741,96],{},": the bigger it is, the more total energy you have to supply.",[358,1744,1745,1748],{},[16,1746,1747],{},"Local climate",": in the north the demand is higher; in the south conditions are more\nfavourable.",[358,1750,1751,1754,1755,1758],{},[16,1752,1753],{},"Thermal cover",": a cover or roller shutter sharply reduces losses. ",[218,1756,1757],{},"A good cover can\nhave as much impact as a more powerful heat pump"," — it is often the most profitable\ninvestment.",[358,1760,1761,1764],{},[16,1762,1763],{},"What you are aiming for",": holding 28 °C in high summer is nothing like extending the\nseason from April to October.",[13,1766,1767],{},[992,1768],{"alt":1769,"height":995,"src":1770,"width":997},"An uncovered pool compared with one under a thermal cover: the cover sharply reduces heat loss","\u002Fillustration-4-effet-bache-en.svg",[77,1772,1774],{"id":1773},"_10-how-to-read-a-heat-pump-spec-sheet-properly","10. How to read a heat pump spec sheet properly",[13,1776,1777],{},"The survival checklist:",[355,1779,1780,1787,1790,1796],{},[358,1781,1782,1783,1786],{},"✅ the heating power ",[16,1784,1785],{},"with its condition"," (Air _° \u002F Water _° \u002F Humidity _%);",[358,1788,1789],{},"✅ the power at 15 °C, if your use is extended;",[358,1791,1792,1793,1103],{},"✅ the corresponding COP ",[16,1794,1795],{},"and its condition",[358,1797,1798],{},"✅ the operating range (minimum outside temperature).",[13,1800,1801],{},"Bad reading: \"9 kW heat pump\".\nGood reading: \"heat pump delivering 9 kW at Air 26 °C \u002F Water 26 °C, and 6.4 kW at Air\n15 °C \u002F Water 26 °C\".",[77,1803,1805],{"id":1804},"_11-what-power-for-your-pool","11. What power for YOUR pool?",[13,1807,1808],{},"No magic formula, but these markers should stop you leaving empty-handed:",[355,1810,1811,1818,1824],{},[358,1812,1813,1814,1817],{},"for ",[16,1815,1816],{},"summer"," use, reason on the power at 26 °C;",[358,1819,1813,1820,1823],{},[16,1821,1822],{},"extended"," use, reason on the power at 15 °C;",[358,1825,1826],{},"a thermal cover changes the result substantially, in the right direction.",[522,1828,1829],{},[13,1830,1831],{},"A good choice starts with an estimate of the pool's real heating demand, then a check that\nthe pump actually supplies that power under realistic conditions.",[13,1833,1834,1835,1838],{},"That is exactly the logic of our ",[16,1836,1837],{},"pool heat pump power calculator",", built on the 15 °C\nreference rather than the shop-window figure:",[741,1840],{"description":1841,"label":1690,"title":35,"to":899},"Our calculator is built on the 15 °C reference rather than the shop-window figure.",[77,1843,1845],{"id":1844},"_12-conclusion","12. Conclusion",[522,1847,1848],{},[13,1849,1850,1851,1854],{},"The right choice is not the heat pump showing the biggest kW number. It is the one that\nsupplies ",[16,1852,1853],{},"enough power in the conditions you will actually use it in"," — and to compare\ntwo models, always check they are talking about the same condition.",[77,1856,750],{"id":749},[752,1858],{},[755,1860,1862,1865],{"icon":757,"title":1861},"Sources",[13,1863,1864],{},"Each reference in the table (§5) links to the manufacturer's or a retailer's spec sheet\nshowing the measurement conditions. Data collected on 18\u002F07\u002F2026; sheets and published\nconditions may change.",[760,1866,1867,1877,1885,1894,1903,1912,1921,1930,1939,1948],{},[358,1868,1869,1872,1873],{},[16,1870,1871],{},"Poolex — Silverline On\u002FOff 7 kW"," — ",[770,1874,1875],{"href":1875,"rel":1876},"https:\u002F\u002Fwww.poolex.fr\u002Ffr\u002Fproduit\u002Fpompe-a-chaleur-piscine-poolex-silverline-on-off",[774],[358,1878,1879,1872,1882],{},[16,1880,1881],{},"Poolex — Silverline On\u002FOff 15 kW",[770,1883,1875],{"href":1875,"rel":1884},[774],[358,1886,1887,1872,1890],{},[16,1888,1889],{},"Poolex — Silverline Fi 90 (Full Inverter)",[770,1891,1892],{"href":1892,"rel":1893},"https:\u002F\u002Fwww.esc-grossiste.fr\u002Fboutique\u002Fpompe-a-chaleur-piscine\u002F46094-pompe-a-chaleur-piscine-silverline-fi-full-inverter-poolex.html",[774],[358,1895,1896,1872,1899],{},[16,1897,1898],{},"Poolex — Silverline Top 12 (Full Inverter)",[770,1900,1901],{"href":1901,"rel":1902},"https:\u002F\u002Fwww.poolex.fr\u002Ffr\u002Fproduit\u002Fpompe-a-chaleur-piscine-poolex-silverline-top",[774],[358,1904,1905,1872,1908],{},[16,1906,1907],{},"Astralpool — Eco Elyo-13 (Full Inverter)",[770,1909,1910],{"href":1910,"rel":1911},"https:\u002F\u002Fwww.quimipool.com\u002Fen\u002F13590-heat-pump-astralpool-eco-elyo-13-full-inverter.html",[774],[358,1913,1914,1872,1917],{},[16,1915,1916],{},"Astralpool — Eco Elyo-20 (Full Inverter)",[770,1918,1919],{"href":1919,"rel":1920},"https:\u002F\u002Fwww.quimipool.com\u002Fen\u002F13589-heat-pump-astralpool-eco-elyo-20-full-inverter.html",[774],[358,1922,1923,1872,1926],{},[16,1924,1925],{},"GRE — HPGIC45 (Full Inverter)",[770,1927,1928],{"href":1928,"rel":1929},"https:\u002F\u002Fwww.piscinehorssol.com\u002Fpompe-a-chaleur-full-inverter-pour-piscines-hors-sol-ou-enterrees-jusqua-45-m3",[774],[358,1931,1932,1872,1935],{},[16,1933,1934],{},"GRE — HPGIC75 (Full Inverter)",[770,1936,1937],{"href":1937,"rel":1938},"https:\u002F\u002Fwww.grepool.com\u002Ffr\u002Fpompes-a-chaleur\u002Fpompes-a-chaleur-inverter\u002Fhpgic75",[774],[358,1940,1941,1872,1944],{},[16,1942,1943],{},"Zodiac — PX25 (Full Inverter, published at 15 °C, NF PAC)",[770,1945,1946],{"href":1946,"rel":1947},"https:\u002F\u002Fwww.zodiac-poolcare.fr\u002Fchauffage\u002Fpompes-a-chaleur\u002Fgamme-bassins-residentiels\u002Fpx25",[774],[358,1949,1950,1872,1953],{},[16,1951,1952],{},"Hayward — EnergyLine Pro ENP5 (published at 15 °C, NF-414)",[770,1954,1955],{"href":1955,"rel":1956},"https:\u002F\u002Fwww.hayward.fr\u002Fcategories\u002Fpompes-a-chaleur-piscine",[774],[1958,1959],"feedback-thumbs",{},{"title":283,"searchDepth":847,"depth":847,"links":1961},[1962,1963,1964,1968,1973,1978,1979,1980,1981,1982,1983,1984,1985],{"id":947,"depth":847,"text":948},{"id":969,"depth":847,"text":970},{"id":1086,"depth":847,"text":1087,"children":1965},[1966,1967],{"id":1090,"depth":855,"text":1091},{"id":1115,"depth":855,"text":1116},{"id":1133,"depth":847,"text":1134,"children":1969},[1970,1971,1972],{"id":1137,"depth":855,"text":1138},{"id":1190,"depth":855,"text":1191},{"id":1217,"depth":855,"text":1218},{"id":1253,"depth":847,"text":1254,"children":1974},[1975,1976,1977],{"id":832,"depth":855,"text":1260},{"id":1288,"depth":855,"text":1289},{"id":1546,"depth":855,"text":1547},{"id":1598,"depth":847,"text":1599},{"id":1634,"depth":847,"text":1635},{"id":1694,"depth":847,"text":1695},{"id":1731,"depth":847,"text":1732},{"id":1773,"depth":847,"text":1774},{"id":1804,"depth":847,"text":1805},{"id":1844,"depth":847,"text":1845},{"id":749,"depth":847,"text":750},"2026-08-14","2026-07-18","The kW printed on a pool heat pump is measured at 26 °C air. At 15 °C, real power drops by about 29 %. How to read a spec sheet properly.",[1990,1993,1996,1999,2002,2005],{"q":1991,"a":1992},"Does a 9 kW heat pump always deliver 9 kW?","No. That 9 kW figure belongs to one specific test condition, usually 26 °C air and 26 °C water. When the air is cooler the real output falls: at 15 °C a pump advertised as \"9 kW\" at 26 °C often delivers only about 6.4 kW.",{"q":1994,"a":1995},"Should I look at the power at 26 °C or at 15 °C?","It depends on how you use the pool. For swimming limited to July and August, the 26 °C figure is representative. For an extended April-to-October season in France, look at the 15 °C figure, because that is what reflects shoulder-season conditions.",{"q":1997,"a":1998},"How big is the gap between advertised power and real power at 15 °C?","In our survey of 10 references (July 2026) the average gap is about −29 % for models advertised at 26 °C, ranging from −21 % to −33 %. Some certified brands, such as Zodiac and Hayward, publish their power at 15 °C instead, so for those the gap is effectively nil.",{"q":2000,"a":2001},"What is a good COP for a pool heat pump?","COP — the ratio of heat delivered to electricity consumed — also depends on conditions. The headline \"up to 12–16\" figures are measured at 26 °C. At 15 °C a good COP sits around 4 to 6, which is already excellent and is the realistic number to plan with.",{"q":2003,"a":2004},"Do all brands inflate their advertised power?","No. The advertised figure is accurate within its own test condition. Most brands quote at 26 °C, the most flattering one, but some (Zodiac, Hayward) quote at 15 °C under the French NF PAC \u002F NF-414 certification. The real problem is not dishonesty, it is comparing two figures measured under different conditions.",{"q":2006,"a":2007},"What size heat pump does my pool need?","It depends on pool volume, target temperature, region, how long a season you want and whether the pool is covered. A reliable estimate starts from the pool's actual heat demand, then checks that the pump delivers that power under realistic conditions; a professional's confirmation is still recommended before buying.","\u002Fog\u002Fog-pool-heat-pump-power-en.png",{},"article",{"title":906,"description":1988},"en\u002Fpool\u002Freal-vs-advertised-heat-pump-power","pool-heat-pump-power","lfWrM__XQIj0eAF_7qTPHZk9ZrsPCWLcf5aAUAIXKIo",{"en":2016,"fr":2018},{"category":2017},"pool",{"category":2019},"piscine",1788608752672]