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Size your heat pump.

See the EvoHeat and Madimack models that fit, and what it costs to run. The numbers update as you go. It's an estimate from our own formula; the final size is confirmed with you after we've seen photos.

Your pool
8.0 m
4.0 m
1.4 m
I know the litres
litres

Uses the average depth above to work out the surface area.

Swim season When do you want to swim?
Water temperature
Your backyard
Cover at night
Sun and wind
c / kWh

On your power bill. Enter your own rate; 30c is used as a default.

The live update needs JavaScript. Without it, press after changing a value.

Method

How the numbers
are worked out.

A simplified formula giving an indicative heating need and running cost, then matched to real EvoHeat and Madimack models using their published heating output and C.O.P. at 15°C and 27°C air.

Volumelength × width × depth × 1,000 L
Heating needarea × 0.34 × season × temperature × cover × exposure
SeasonOct–Apr 1.00 · Sep–May 1.15 · All year 1.40
Temperature±8% per °C from 28
Cover · Exposure0.83 · 1.20
Air temperatureBrisbane monthly mean, BoM station 040913 (mean max + mean min) ÷ 2
Model outputPublished full-output kW at 15°C and 27°C air, interpolated to the coldest month of your season
ModelsIn each range, the smallest single-phase model whose output in that month meets the need. Ranges whose smallest fit is over 1.5 × the need + 3 kW are left out as oversized
Running costEach month's heat ÷ that model's published full-output C.O.P. at that month's air temperature × c/kWh. Range spans the fitting models, ±10%
Warm-upvolume × +6°C ÷ the smallest fitting model's output, losses ignored

Model data

Every model the calculator uses.

Heating output and C.O.P. at full output, as published by each manufacturer. Three-phase models are listed but not matched automatically.

EvoHeat Force Ai8 models
ModelkW at 27°CkW at 15°CC.O.P. 27° / 15°Power
Force-Ai 1310.78.37 / 5.115 amp plug
Force-Ai 1613.610.27 / 515 amp plug
Force-Ai 1917.113.17.3 / 5.4Hardwired
Force-Ai 2220.616.17.9 / 5.6Hardwired
Force-Ai 282620.47 / 5Hardwired
Force-Ai 3230.124.47 / 5.1Hardwired
Force-Ai 32-330.124.47 / 5.1Hardwired, three-phase
Force-Ai 40-33828.97 / 4.8Hardwired, three-phase

Source: EvoHeat 2026 Residential Pool Heating Catalogue + Force-Ai trade brochure (emailed to PEA by EvoHeat QLD/NT BDM, 26 Oct 2026). Rating: air 27°C / water in 26°C / out 28°C; low point air 15°C / water in 26°C. Product page

EvoHeat Fusion-i Pro8 models
ModelkW at 27°CkW at 15°CC.O.P. 27° / 15°Power
Fusion-i Pro 7755.9 / 4.410 amp plug
Fusion-i Pro 99.46.66 / 4.510 amp plug
Fusion-i Pro 1312.39.16 / 4.615 amp plug
Fusion-i Pro 1615.5116 / 4.7Hardwired
Fusion-i Pro 191812.55.7 / 4.7Hardwired
Fusion-i Pro 2424.618.66.3 / 4.8Hardwired
Fusion-i Pro 28-328.921.46.4 / 4.9Hardwired, three-phase
Fusion-i Pro 35-332.424.45.5 / 5.4Hardwired, three-phase

Source: EvoHeat 2026 Residential Pool Heating Catalogue + Force-Ai trade brochure (emailed to PEA by EvoHeat QLD/NT BDM, 26 Oct 2026). Rating: air 27°C / water in 26°C / out 28°C; low point air 15°C / water in 26°C. Product page

EvoHeat Dynamic-i Pro3 models
ModelkW at 27°CkW at 15°CC.O.P. 27° / 15°Power
Dynamic-i Pro 502418.66.8 / 4.8Hardwired
Dynamic-i Pro 6028.120.66.5 / 4.9Hardwired
Dynamic-i Pro 70332.925.66.1 / 4.6Hardwired, three-phase

Source: EvoHeat 2026 Residential Pool Heating Catalogue + Force-Ai trade brochure (emailed to PEA by EvoHeat QLD/NT BDM, 26 Oct 2026). Rating: air 27°C / water in 26°C / out 28°C; low point air 15°C / water in 26°C. Product page

Madimack InverELITE V49 models
ModelkW at 27°CkW at 15°CC.O.P. 27° / 15°Power
InverELITE V4-10010.277 / 5.610 amp plug
InverELITE V4-120128.17.2 / 5.710 amp plug
InverELITE V4-150159.87.2 / 6.110 amp plug
InverELITE V4-17017.5127.2 / 5.8Hardwired
InverELITE V4-19019.5137 / 5.5Hardwired
InverELITE V4-23023157.3 / 6Hardwired
InverELITE V4-2802819.37.2 / 5.7Hardwired
InverELITE V4-3403423.57.1 / 5.7Hardwired
InverELITE V4-42042307.8 / 5.5Hardwired, three-phase

Source: madimack.com/au product specification tables (fetched 26 Oct 2026). Rating: air 27°C / water 27°C / 80% RH; low point air 15°C / water 26°C / 70% RH. Product page

Madimack InverELITE V37 models
ModelkW at 27°CkW at 15°CC.O.P. 27° / 15°Power
InverELITE V3 ESV3-11011.57.77.3 / 510 amp plug
InverELITE V3 ESV3-140149.37.4 / 5.115 amp plug
InverELITE V3 ESV3-1701711.57.1 / 5Hardwired
InverELITE V3 ESV3-22022.5157.1 / 5.1Hardwired
InverELITE V3 ESV3-27026.9187.3 / 5.1Hardwired
InverELITE V3 ESV3-32031.821.87.2 / 5.2Hardwired
InverELITE V3 ESV3-40040.5297 / 5.1Hardwired, three-phase

Source: madimack.com/au product specification tables (fetched 26 Oct 2026). Rating: air 27°C / water 27°C / 80% RH; low point air 15°C / water 26°C / 70% RH. Product page

Madimack InverECLIPSE Plus3 models
ModelkW at 27°CkW at 15°CC.O.P. 27° / 15°Power
InverECLIPSE Plus 16kW16.511.77.2 / 5.115 amp plug
InverECLIPSE Plus 21kW2115.17 / 5Hardwired
InverECLIPSE Plus 26kW2618.66.9 / 4.8Hardwired

Source: madimack.com/au product specification tables (fetched 26 Oct 2026). Rating: air 27°C / water 27°C / 80% RH; low point air 15°C / water 26°C / 70% RH. Product page

Madimack InverECO Plus6 models
ModelkW at 27°CkW at 15°CC.O.P. 27° / 15°Power
InverECO Plus 9kW96.56.2 / 4.2Single phase
InverECO Plus 13kW1396.3 / 4.5Single phase
InverECO Plus 16kW16116.2 / 4.3Single phase
InverECO Plus 20kW20.2146.2 / 4.2Single phase
InverECO Plus 24kW24.2166.3 / 4.5Single phase
InverECO Plus 28kW2819.56.3 / 4.4Single phase

Source: madimack.com/au product specification tables (fetched 26 Oct 2026). Rating: air 27°C / water 27°C / 80% RH; low point air 15°C / water 26°C / 70% RH. Product page