Heat pump calculation tools

Applications
1

New menu and link to source code
I’ve updated the collection of heat pump calculation tools that I’ve been building slowly over the last few years to have a menu system and link to the GitHub source code. This should improve navigation and provide a more connected experience.

Note: While some of these tools have been developed with testing on mobile, most are best viewed on a wider screen and need more work for a nice mobile experience.

New tool: Weather Compensation calculator

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List of available tools:

Other tools

The following are developed by OpenEnergyMonitor (SAP.js and the ZCB model in collaboration with CarbonCoop and The Center for Alternative Technology) but are not integrated into this site:

  • HeatLoss.js
    An open source room by room heat loss calculator.

  • SAP.js
    An open source javascript implementation of the SAP 2012 monthly building energy model.

  • ZeroCarbonBritain energy model
    An open-source javascript implementation of the 10-year hourly cross sectoral UK energy model behind the ZeroCarbonBritain scenario.

5 Likes
3

Hi @TrystanLea,
Is there any mileage in adding a little tool for roomstat setback recovery time, as outlined in House Thermal Inertia and Roomstat Setback (some cautionary notes)? It seems to have been fairly well received…

1 Like
4

Thanks Sarah, I will have a good read and see what I can add.

6

Another mini tool added, quickly enter K1, P+, K2 & K3 radiators, calculate both total rated output and heat output at lower flow temperatures. Radiator data based on fitting equations to the Stelrad radiator tables “Elite” range which I think is actually just standard rads.

https://openenergymonitor.org/tools/RadSchedule

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The curve fitting of the stelrad tables is quite nice, if I might say so myself :joy:

  • The height component is 2nd order polynomial
  • The length component is linear
  • Yes all those decimal places did seem to be required!
calculate_rated_output: function(type, height, length) {
    var m = 0;
    var output = 0;

    if (type == "K1") {
        m = -0.000000454*Math.pow(height,2)+0.002017178*height-0.047435696;
        output = Math.round(m * length);
    }
    else if (type == "P+") {
        m = -0.000000567*Math.pow(height,2)+0.002620013*height+0.040997375;
        output = Math.round(m * length);
    }
    else if (type == "K2") {
        m = -0.00000058*Math.pow(height,2)+0.00308043*height+0.14058005;
        output = Math.round(m * length);
    }
    else if (type == "K3") {
        m = -0.000000961*Math.pow(height,2)+0.004518773*height+0.1489;
    }

    output = Math.round(m * length);

    return output;
}
3 Likes
7

A tool when someone can enter the heatlose for each room and the radator lengths along with max possible height, that then calculates type/height combination for each possible flow temperature may be useful to many people. (Eg what can be easily done with existing pipework.)

1 Like