{
  "url": "https://openlegislation.uk/boiler-efficiency-regulations-1993/schedule-2",
  "json_url": "https://openlegislation.uk/boiler-efficiency-regulations-1993/schedule-2.json",
  "legislation": "uksi/1993/3083",
  "legislation_title": "The Boiler (Efficiency) Regulations 1993",
  "legislation_url": "https://openlegislation.uk/boiler-efficiency-regulations-1993",
  "path": "schedule/2",
  "kind": "schedule",
  "number": "2",
  "heading": "THE EFFICIENCY REQUIREMENTS",
  "text": "Boilers must comply with the useful efficiency requirements set out in the Table below —\n(a) at rated output, that is, operating at rated output Pn expressed in kW, at an average boiler-water temperature of 70°C, and\n(b) at part load, that is, operating at 30% part load, at an average boiler-water temperature which varies according to the type of the boiler.\nTable\nType of boiler\nRange of power output\nEfficiency at rated output\nEfficiency at part load\nkW\nAverage boiler-water temperature expressed in °C\nEfficiency requirement expressed in %\nAverage boiler-water temperature expressed in °C\nEfficiency requirement expressed in %\n* Including condensing boilers using liquid fuels.\n** Temperature of boiler water supply.\nStandard boilers\n4 to 400\n70\n≥84 + 2 log Pn\n≥50\n≥80 + 3 log Pn\nLow temperature boilers\n4 to 400\n70\n≥87.5 + 1.5 log Pn\n40\n≥87.5 + 1.5 log Pn\nGas condensing boilers\n4 to 400\n70\n≥91 + 1 log Pn\n30\n≥97.1 + 1 log Pn",
  "extent": null,
  "status": null,
  "version": "current",
  "annotations": [
    {
      "type": "footnote",
      "label": "f1",
      "text": "* Including condensing boilers using liquid fuels."
    },
    {
      "type": "footnote",
      "label": "f2",
      "text": "** Temperature of boiler water supply."
    }
  ],
  "outstanding_effects": [],
  "provenance": {
    "source": "legislation.gov.uk",
    "source_url": "https://www.legislation.gov.uk/uksi/1993/3083/schedule/2",
    "retrieved_at": "2026-10-29T13:45:05.409452+00:00"
  },
  "licence": "Open Government Licence v3.0",
  "licence_url": "https://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/",
  "attribution": "Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives."
}