The New Engineer — HVAC MCP Server

EN 378 applied to BUILDING projects, volume by volume. An installation does not occupy one room but several: the machine, the rooms crossed by refrigerant lines, the rooms served by indoor units. Each volume is classified on its own — access category (a/b/c) and location class (I–IV) — and each classification calls for its own measures. The tool answers per volume, never as a single verdict. It returns, for every volume: its classification and why, the charge limit from Tables C.1 and C.2 of EN 378-1 (with the C.2 formula computed when the table calls for it), whether the charge exceeds it, the EN 378-3 measures that follow, the applicable texts (EN 378-1 to -4, EN IEC 60079-10-1, SUVA 66139 and 2153) and the ventilation flow rates. FOUR CONFIGURATIONS COVER ALMOST EVERY BUILDING PROJECT. Bring the user's case back to one of them wherever possible: machine_en_local_technique chiller or heat pump, all refrigerant inside the machine, standing in a plant room -> c III enceinte_accessible_fermee all refrigerant inside a walk-in ventilated enclosure that stays closed even for maintenance -> the enclosure is c III, the room around it carries no requirement enceintes_inaccessibles one or more units, each in a manufacturer's non-accessible ventilated enclosure -> TWO analyses: the enclosure in operation (class IV, the manufacturer sizes and justifies it, ask him for the enclosure ventilation), and the plant room with the enclosure OPEN for maintenance, which comes back to c III split_traversant split or VRF outdoors, refrigerant lines crossing occupied rooms -> each room on its own; offices and their circulations are b I, and formula C.2 gives the maximum charge for the floor area, or the minimum floor area for the charge THIS TOOL ANSWERS SAFETY IN THE ROOM. It says NOTHING about whether the refrigerant may still be placed on the market or refilled: in Switzerland that is `check_refrigerant_switzerland`. A question that mixes both - « may I use R-32 for 3 kg in a server room, and until when can I refill it » - needs BOTH tools: call this one for the room, and check_refrigerant_switzerland for the dates. Do not answer half the question. NEVER guess. The refrigerant, the configuration and the charge are always needed; a split also needs the floor area and how the indoor unit is mounted (floor, wall, window, ceiling), since C.2 depends on it. Without them the result is `provisional` and carries `questions_to_ask`: ask them, one or two at a time, then call again. Answer from `answer_outline`, volume by volume. In building projects, detection is preferred over treating a plant room as an ATEX zone. C.3 is never used. Say that the practical limit alone proves nothing: the charge limit of Tables C.1 and C.2 is what counts. SCOPE: building services. Cold rooms, food refrigeration and industrial process refrigeration are a different trade.

Swiss refrigerant regulation check (ORRChim / ChemRRV annex 2.10, OFEV synthesis of May 2026, rules adopted 29.10.2025) plus refrigerant data from EN 378-1 Annex E: GWP (AR4, the ORRChim basis), ODP, LFL, safety class, practical limit. Returns, for a given refrigerant and installation: the date from which machines using it can no longer be placed on the Swiss market (import from 01.01.2027, sale to third parties from 01.07.2027), the date from which filling with virgin refrigerant is banned, the period when only reclaimed refrigerant may be used, and the date from which all filling is banned. SCOPE: heating, air conditioning, building cooling and process cooling, data centres included. NOT food refrigeration, cold rooms or deep freezing: those are a different trade, and the tool declines them instead of answering. Use it whenever the user asks about a refrigerant in Switzerland — its GWP / PRG, flammability, whether a chiller, heat pump, split, VRF or cold room using it may still be sold or refilled — in any language: fluide frigorigène, Kältemittel, refrigerante, refrigerant, R-32, R-410A, R-290, CO2, NH3... The answer depends on the installation. The regulation distinguishes: use (building cooling, food refrigeration medium / low temperature / combined / deep freezing, process cooling, heat pump mainly for heating, ice rink), cooling capacity Q0K or heating capacity Q0H, self-contained (factory-built packaged unit) or not, split, direct expansion (incl. VRF), secondary coolant loop (chilled water / brine), air-cooled condenser and refrigerant charge. THIS TOOL ANSWERS ONE QUESTION ONLY: may the refrigerant still be sold and refilled in Switzerland, and until when. It says NOTHING about safety in the room - charge limits, machine room, detection, ventilation, ATEX. That is `check_en378_zones`. A question that mixes both - « may I use R-32 for 3 kg in a server room, and until when can I refill it » - needs BOTH tools: call this one for the dates, and check_en378_zones for the room. Do not answer half the question. NEVER guess these. Call the tool with what the user gave: it returns `provisional: true`, the possible `scenarios`, and `questions_to_ask` in the order that matters most. Ask them (one or two at a time), then call again. Natural refrigerants need no questions. Build your answer on `answer_outline`; quote exceptions as possible, never as granted.

Size the expansion vessel and pressurisation of a closed heating or chilled-water circuit to EN 12828: static height, minimum pressure p0, fill pressure pa, final pressure pe, expansion volume, water reserve, nominal vessel volume with the standard vessel to buy, safety valve setting together with the minimum it must not fall below, pressure class of the lowest equipment, intermediate vessel when needed. Heights become pressures through the real density of the fluid, at the temperature that matters for each: the coldest for p0, the design temperature for the valve and the lowest point. Water and glycols therefore give different figures for the same height. Use it whenever the user asks to size or check an expansion vessel, pressurisation unit, pre-charge pressure or safety valve — in any language: vase d'expansion, maintien de pression, Ausdehnungsgefäss, Druckhaltung, vaso di espansione, vaso de expansión. Needs the installation water volume and THREE heights, all measured from the point where the expansion vessel connects to the network: - the highest point of the installation, above it; - the lowest point, usually below it (negative) or level with it; - the safety valve, which always sits on the heat generator or chiller. If the user does not know it, it is assumed 1 m above the vessel connection, and the result says so. Ask the user for the volume and the three heights before calling. NEVER invent a height: if the lowest point or the valve height is unknown, omit it. The result is then marked provisional and lists the questions to ask. Build your answer on `answer_outline`: it carries the assumptions, the questions and the link to the website, which measures all of these on the user's IFC model.