New Heating Law: Sorting Customer Questions in a Heating Installer's Chat

When the heating season begins, heating installers and plumbing and heating firms receive questions that at first have little to do with a service visit or a quote. May I still have a gas boiler installed? What does the new law mean for my old oil heating? Is there funding for it? The occasion is a change in the law from the summer: the act amending the Buildings Energy Act was published in the Federal Law Gazette at the end of July (BGBl. 2026 I No. 226), and gesetze-im-internet.de now lists the act under the name Gebäudemodernisierungsgesetz, GModG for short. Many customers know about the change from the news and from talking to neighbours, rarely from the wording. This article shows how an assistant on a heating installer's website answers the general questions from the firm's own explainer, hands the individual case to a person, takes an enquiry about replacing a heating system with the details needed and keeps a breakdown in winter apart from all of that.

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Labels in the illustration

• Question in chat
• Category
• What the assistant does
• “What is in Section 43 GModG?”
• About the law
• wording, name, steps
• Answer from the explainer
• usually with source and the firm's as-of date
• “Does it apply to my house?”
• Individual case
• duty, exemption, funding
• Handover to a person
• fixed block: no legal advice, with history
• “Quote for a replacement?”
• Enquiry
• replacement, on-site visit
• Details, photos, booking request
• travel buffer, binding only once confirmed
• “Heating off, house cold”
• Breakdown
• no heat in the cold season
• Emergency number or callback
• danger to life: emergency services first
• Steps under Section 43 (1) GModG
• installed after 29 July 2026
• in an existing building;
• minimum share of heat from
• biomethane, bio-oil, biogenic
• LPG or hydrogen
• min. 10%
• from 1 Jan 2029
• min. 15%
• from 1 Jan 2030
• min. 30%
• from 1 Jan 2035
• min. 60%
• from 1 Jan 2040

New heating law: sorting customer questions in chat

Heating season and a new name for the law

For heating installers, the change in the law falls into the period that is busiest anyway. In autumn, the service visits are running, the first systems fail, and anyone thinking about a replacement wants clarity before winter. On top of that, not only the content has changed but also the name. The act amending the Buildings Energy Act, the Building Electromobility Infrastructure Act and further provisions on heating has been published as BGBl. 2026 I No. 226. On gesetze-im-internet.de, the act now bears the title “Act on Saving Energy and Modernising the Heat Supply in Buildings”, Gebäudemodernisierungsgesetz or GModG for short. Anyone who reads the new name in the news and knows the old one from the last advice meeting will ask.

On the phone the questions sound similar, and yet there are two kinds in them. One concerns the law: what it says, from when it applies, what the new terms mean. The other concerns one's own house: whether the duty applies to this system, whether an exemption applies, what a replacement costs and whether there is money for it. For the first kind, a good written explanation is enough; for the second, it takes a conversation with someone who knows the house and the system. An assistant on the website is useful when it separates these two kinds cleanly. How it takes enquiries in the trades in general is described in the article on the AI assistant for trade businesses. In the heating season, these questions typically come in:

• May I still have a gas or oil heating system installed? The most frequent question. The assistant repeats what Section 43 para. 1 GModG attaches to such an installation; whether it makes sense in one's own house is clarified in the advice meeting.
• What applies to my existing system? This is usually where the individual case begins, because the answer depends on the system, the building and the ownership situation.
• Does the law have a new name? A question about the name that can be answered in general: GModG is the new title, and the reference is at the same address.
• What is the green gas quota? This refers to the green gas and green heating oil quota announced in Section 42a GModG, whose law is still to be presented.
• Is there funding, and how much? The assistant does not promise funding and does not state rates; it passes on what the firm has stored on the subject and records the question for the meeting.
• What does a replacement cost? Without a stored basis, the assistant does not state a price; the question leads to an enquiry with an on-site appointment.
• My heating has broken down. Do I now have to replace it under the new law? Two questions in one: the breakdown goes to the emergency service, the legal question to the advice meeting.

What the law actually says

Section 43 GModG addresses the question of installation in its very heading: “Installation of a heating system fired with gas, heating oil or liquefied petroleum gas”. Subsection 1 ties the duty to three features: such a system, an installation after 29 July 2026 (Section 43 para. 1 GModG) and an existing building. The duty lies with the owner of the building. The wording:

Three things stand out on reading, and all three matter for the chat. First, according to its wording, subsection 1 applies to installation “in an existing building”; what applies to a new building is not governed by this subsection, and the assistant should not derive it from it. Second, the duty is addressed to the owner; if the owner is not the operator of the heating system, under subsection 6 the operator has to fulfil it. Third, Section 43 contains further subsections through which the duty can be met in other ways or which postpone it: the use of a solar thermal system (subsection 3), a ventilation system with heat recovery (subsection 4), a heat pump hybrid heating system (subsection 5) and installation after an irreparable failure of the existing system (subsection 7). Which of these routes comes into question for a particular house is not a piece of information but an assessment.

The second provision customers ask about comes immediately before it. Section 42a GModG bears the heading “Green gas/green heating oil quota” and announces a further law: the Federal Government is to present it by 1 December 2026 (Section 42a GModG). According to the wording, this law will oblige those who place gas, oil and LPG on the market to switch the fuels for heating buildings completely to climate-neutral fuels from the year 2045 (Section 42a GModG). The quota has thus been announced but, according to the wording of Section 42a, not yet introduced, and what it will contain is something no one can reliably answer in a chat today. A look at the list of sections also shows that Sections 71 to 73 are listed there as repealed. A leaflet or a page of the website based on the old structure therefore needs revising before an assistant answers from it.

Explain the law, do not assess the house

The assistant's basis for answers is an explainer that the firm writes and approves, plus the pages of its website. In the default setting, XICBOT answers exclusively from this stored material and usually names the excerpts used as its source; the operator can relax this setting per version, which is not advisable for a legal topic. If something is in neither the explainer nor those pages, the assistant does not add it from general knowledge but says that nothing on it has been stored. How this binding works is described on the knowledge base page.

The second line is built in. XICBOT comes with four hard subject blocks that no setting lifts; one of them is the block on legal advice. It prohibits the assistant from assessing an individual case, from stating which deadline applies in the customer's case or whether it has been met, and from assessing prospects of success or claims; it states a deadline that appears in a stored excerpt, usually with its source. If a question touches this block, the assistant says in one sentence that it may not assess this, names the way to a person and hands over the conversation. In addition, the service checks the finished answer once more against these blocks. This is not a keyword list that hands over by itself on words such as “heating law”. Anyone who wants certain terms reliably passed to a person, such as the German word stem “Förder”, which covers the words for funding, funding programmes and funding applications, or “exemption”, maintains them as the assistant's own signal words; if such a word appears in the question, the conversation is handed over. The search matches parts of words and also covers the answer: if an answer contains the word, it receives the notice on the limit.

One point deserves a test of its own. The fixed block covers the deadline in one's own case, not the deadline as a factual detail: if the wording of Section 43 is in the explainer, the assistant repeats it, usually with its source, even though the steps are dates; whether a step applies to one's own house or a date has been met is something it is not meant to assess. Where a question touches this line depends on its wording, and depending on how it is worded the assistant may still refer even a general question about the steps to a person instead of repeating the wording. That is the more cautious direction, but it should be known before customers write. Before going live, check both forms in a test conversation: the general question (“What does Section 43 GModG say?”) and the personal one (“Does this apply to my house?”). How an assistant declines helpfully instead of guessing is described in the article on declining instead of guessing.

The explainer as the key source

The explainer is neither a legal opinion nor an advertisement for a particular technology. It is a short, approved page or file in which the firm records what the law says, how it advises and where customers turn with their individual case. Because the assistant answers mainly from it, this text determines how good the answers will be. The pages of the website, however, also form part of the basis for answers: older pages on the Buildings Energy Act that still rely on the old structure are revised or excluded from being read into the knowledge base with an exclusion pattern; otherwise the assistant also answers from them. The explainer itself should contain these building blocks:

• The wording of Section 43 para. 1 GModG with a deep link to gesetze-im-internet.de, plus the three features: gas, oil or LPG heating, installation after the cut-off date, existing building.
• The reference to Section 42a GModG with the sentence that the law on the green gas and green heating oil quota has been announced and is still to be presented.
• Both names, Buildings Energy Act and Gebäudemodernisierungsgesetz, so that customers recognise their question.
• An as-of date at the top of the text that is kept up to date with every change.
• The sentence on the individual case: whether a duty applies to a particular house and which route fits is clarified in the advice meeting, not in the chat.
• The route to funding as the firm describes it, without rates and without promises, with a reference to the advice meeting.
• The procedure for an enquiry about replacing the heating, and the emergency number for a breakdown.

How well the binding to stored material holds is shown by our own measurement series of 11 September 2026: 42 of 48 answers to questions whose answer is in the knowledge base carried a source reference; six did not. Of eight questions deliberately outside the material, the assistant declined 8 of 8 instead of guessing. The details are on the measurements page. For an explainer on heating law this means: what is not in it is usually not invented, and what is in it should be worded so that an answer with a source is possible.

Questions about one's own house go to a person

The line between information and individual case can be recognised by the wording. “What does Section 43 govern?” is a question to the law. “Do I have to do anything about my 2009 gas boiler?” is a question about one's own house, and it needs details that are not fully available in the chat: who is the owner and who the operator, which system was installed when, whether a replacement is due and in which way a duty could be met. The following overview shows how the assistant classifies typical questions.

The handover itself is a fixed procedure. The request for a person can be reached in every state of the conversation; when it is handed over, the conversation switches to escalated, appears in the inbox as a handover and a responsible person is notified, together with the history so far. If nobody is available at the moment, the assistant says so and offers the asynchronous route. The customer then usually does not have to explain the question again. How such a handover should be set up is described in the article on handing over to staff. The same pattern of general information and a prepared handover is shown in the article on the firm chat about e-invoicing, there with a tax deadline.

Taking the enquiry about replacing the heating

Many conversations about the law end with a wish for a quote or an on-site consultation. At this point the assistant switches from information to taking details. It asks for contact details and the matter in the flow of the conversation, not through a form placed in front of it, and which details are mandatory is set by the firm per type of matter. For a heating replacement, these details are useful:

• Type of building: detached house, semi-detached house, apartment building or commercial, plus whether the customer is owner, landlord or tenant.
• System: fuel, that is gas, oil, LPG or other, and the approximate age, as far as the customer knows it.
• Living area: a rough figure is enough for preparation.
• Photos: rating plate of the heat generator and the boiler room with flue and storage tank, as attachments in the chat.
• Occasion: a planned replacement, a modernisation or a breakdown that prompted the question.
• Contact and time frame: name, phone number or email address, location and preferred period for the on-site appointment.

For the photos, the assistant uses the attachment function in the chat. In XICBOT it is switched off by default and is switched on per assistant. Images are accepted as PNG, JPEG or WebP, and documents as PDF, with at most five files per conversation; the type of a file is recognised from its first bytes, not from the extension, and an attachment is not delivered in executable form. The files are attached to the case as soon as the enquiry is created and are subject to a retention period of their own. How photos in the chat clarify a matter is described in the article on image upload in chat.

At the end comes the on-site appointment. A booking assistant offers free slots for it from the appointment types the firm has stored: duration, lead time, permitted time windows and buffers, plus a travel buffer for appointments at the customer's premises. The customer picks a time, sees the summary and approves it; this creates an appointment request, not a booking. It only becomes binding once the firm confirms it. There is no matching with an external calendar: appointments that are only in the firm's own calendar are not visible to the assistant. For the heating season, a separate appointment type for advice on replacing the heating, kept apart from servicing and breakdowns, is worthwhile.

When the heating breaks down

Not every message about the heating is a question about the law. Someone who writes that the heating has been off since the morning and the house is cooling down needs the emergency service, not the wording. The assistant keeps these cases apart from advice: it gives the emergency number the firm has stored or takes a callback request with the matter already recorded; the callback is a writing action with a log. Whether a replacement is due after the breakdown and what then applies under Section 43 is a second question that is clarified later in the advice meeting. Which details a fault report needs and how urgency levels are defined is described in the article on fault reports in chat.

When the quota law arrives

The explainer is not a one-off piece of work. At the latest when the law on the green gas and green heating oil quota announced in Section 42a is presented or passed, what customers ask and what the firm wants to answer will change. Then the explainer is adapted, the as-of date is reset and the source is linked again. A new run writes a new version of the sections and only switches over at the end; until then, the previous version keeps answering. Who is responsible for this and how often it is checked should be settled before launch. How this can be organised is described in the article on keeping the knowledge base up to date.

• One person at the firm is responsible for the explainer and has a deputy.
• The as-of date is visible in the text so that the assistant can state it along with the source.
• With every change, the wording is taken afresh from gesetze-im-internet.de, not from a press release.
• The website pages on the subject are reviewed at the same time: anything out of date is revised or excluded from reading with an exclusion pattern; otherwise the assistant also answers from it.
• After the change, the typical questions are run once in a test conversation, the general ones as well as the personal ones.
• Questions for which nothing was stored are reviewed regularly; they show the gaps in the explainer.

Rollout in four steps

An explainer on heating law is quickly written once the questions are known, and it only works once the routes behind it are in place. A realistic sequence before winter looks like this:

• Collect questions: go through phone notes and emails from recent weeks and gather the recurring questions on heating law, funding and replacement.
• Write and approve the explainer: wording of Section 43 para. 1 GModG and Section 42a GModG with deep links, both names, as-of date, the sentence on the individual case and the route to advice; revise older website pages on the Buildings Energy Act or exclude them from reading with an exclusion pattern, otherwise the assistant also answers from them.
• Define the routes: appointment type for advice on replacing the heating with a travel buffer, mandatory details for the enquiry, switch on attachments, store the emergency number and the firm's own signal words such as “Förder” for handover.
• Test and review: run general and personal questions, a funding question, a cost question and a breakdown in a test conversation, then go live and review the conversations of the first weeks.

For customers, one thing above all changes: they usually get an answer with a reference to the general question, in the evening too, and for the question about their own house a route to someone who can assess it. The firm may receive fewer calls that only seek confirmation and more enquiries that start with photos and key facts. How an assistant brings together enquiries, photos and the emergency service in the trades is shown on the page about the assistant for trades. If you would like to talk through setting up such an assistant with an explainer, an appointment type and a handover, you can reach us via contact.

Frequent questions