Heat Load Calculator
Helping you select the right hydronic heating products for your home
There are a range of factors that can influence the right choice of products for your home. These include the room size, but also factors such as insulation, window glazing and ambient temperature as well as where you place products in the case of radiators.
When you visit one of our showrooms with your room dimensions and layout, our team of experts will be able to help you determine the kW output you’ll need to achieve the desired temperature, as well as the kinds of products that will best help you achieve this.
To get you started, you can start doing some calculations with our Heat Load Calculator.
Navigation
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/* =========== RESULT BOX =========== */
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} (function () {
const powerFactors = {
"well-double": 0.0415,
"well-single": 0.0460,
"moderate-double": 0.0500,
"moderate-single": 0.0540,
"poor-double": 0.0585,
"poor-single": 0.0625
};
const lengthEl = document.getElementById("hh-length");
const widthEl = document.getElementById("hh-width");
const heightEl = document.getElementById("hh-height");
const insulationEl = document.getElementById("hh-insulation");
const windowsEl = document.getElementById("hh-windows");
const resultSection = document.getElementById("hh-result-section");
const resultEl = document.getElementById("hh-result-value");
const errorEl = document.getElementById("hh-error");
document.getElementById("hh-submit").addEventListener("click", function () {
const length = parseFloat(lengthEl.value);
const width = parseFloat(widthEl.value);
const height = parseFloat(heightEl.value);
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let L = length, W = width, H = height;
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const FT_TO_M = 0.3048;
L *= FT_TO_M;
W *= FT_TO_M;
H *= FT_TO_M;
}
const volume = L * W * H;
const key = insulationEl.value + "-" + windowsEl.value;
const factor = powerFactors[key] || 0;
const kW = volume * factor;
resultEl.textContent = (Math.round(kW * 100) / 100).toFixed(2);
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})();
Heat Load Calculator
Length
Width
Height
Units
Is the house well or poorly insulated? Well Insulated
Moderately Insulated
Poorly Insulated
Window type Double Glazed
Single Glazed
Please enter all dimensions as numbers greater than zero.
Your Calculation Result
The result shown is the minimum suggested output and should be used as a guide only. Ensure the combined heat output of your radiators meets or exceeds this value.
Kilowatts (Δt 50°C)
–
What does this kW mean? +
This number helps you choose a radiator for your room.
Your Heat Source (Heat Pump or Boiler) will be based on the total heat load of your whole home plus hot water needs. Most heat sources modulate, so even a 30 kW boiler can efficiently heat a home with much smaller radiator loads.
Take a look at our radiators, boilers, and heat pumps. Once you've shortlisted some options, please come visit one of our showrooms so we can ensure you have the right combination of products for your home.
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Products
Hunt Heating stock the widest range brands and products available in Australia for hydronic heating and cooling projects
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Showrooms
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