--- title: Site Utilities Checklist for Gas Analysers url: https://www.sarveshanalytics.com/learn/site-utilities-checklist-for-analysers.html description: Plan power, instrument air, calibration gas, vent, drain, cooling water and heating for an online gas analyser installation. updated: 2026-11-02 source: html --- Learn · Installation and integration # Site utilities for gas analysers: power, air, gas, vent and drain Utilities are the part of a project most often forgotten until commissioning. A one-page checklist prevents a delay. Beginner 3 min read Lesson 5 of 6[Installation and integration](https://www.sarveshanalytics.com/learn/track-installation.html) Helpful first: [Where to mount a gas analyser: panel, shelter or field](https://www.sarveshanalytics.com/learn/where-to-mount-a-gas-analyser.html) Quick answer An analyser installation needs more than a power connection: a clean, stable electrical supply, instrument air or nitrogen for blowback and purges, a calibration gas supply with regulators, a safe vent, a drain for condensate, and in some cases heating, cooling or ventilation for the enclosure. List them at design time and note their quality, pressure and consumption. Updated 2 November 2026 · Figures from Sarvesh datasheets **After this lesson you can** - List the utilities an analyser system may need - State the quality or pressure issue for each - Use a checklist at design review ## The checklist | Utility | What to confirm | |---|---| | Electrical supply | Voltage, frequency, load, earth, clean supply or UPS for critical measurements | | Instrument air or nitrogen | Pressure, dryness and oil-free quality for blowback, purges and pumps | | Calibration gas | Cylinders of zero and span gas, regulators in suitable materials, a safe storage place, a way to connect | | Vent | Safe discharge point, back pressure limit, flammable or toxic gas handling | | Drain | Where condensate goes, how it is neutralised or collected | | Heating and cooling | For shelters and enclosures: ambient limits, trace heating for lines and cabinets | | Communications | 4-20 mA, relay and Modbus cable routes to the control system | | Access and lifting | Service space, cable trays, lifting for heavy items | ## Instrument air quality Blowback and purges use compressed air, which must be dry and free of oil so it does not contaminate the sample path. A dew point well below the lowest site temperature prevents condensation in the lines. See [Compressed air quality and dew point (ISO 8573-1)](https://www.sarveshanalytics.com/learn/compressed-air-quality-and-dew-point.html). ## Calibration gas Calibration gas is a utility of its own: certified cylinders, matched regulators, and plumbing that does not alter the gas. Trace-oxygen calibration needs stainless steel and care: [Calibration gases: choosing, handling and certificates](https://www.sarveshanalytics.com/learn/calibration-gases-choosing-and-handling.html). ## Vent and drain - Vent to a safe place for the gas; flammable or toxic gas must not be discharged in a working area. - Keep vent back pressure low and constant: [Sample pressure, flow and fast bypass loops](https://www.sarveshanalytics.com/learn/sample-pressure-flow-and-bypass-loops.html). - Drain condensate to a collection or treatment route; it may be acidic or contain dissolved gases. ## Utilities on the data sheet Many of these questions are on the application data sheet, so that the system is sized with them in mind: [The application data sheet: what to send Sarvesh](https://www.sarveshanalytics.com/learn/the-application-data-sheet-and-what-to-send-us.html). If you are unsure of a value, send what you have. **In short** - List power, air, calibration gas, vent, drain, heating and communications. - Instrument air must be dry and oil-free. - Plan calibration gas storage, regulators and connections. - Vent and drain to safe, suitable places. ## Check your understanding Answer in your head or on paper first, then open the answer. Recalling an answer teaches more than rereading. **Name three utilities besides electrical power.** Instrument air or nitrogen, calibration gas, and a vent or drain. **Why must blowback air be dry and oil-free?** Wet or oily air contaminates the sample path and filters. **Why avoid high back pressure on the vent?** It changes the sample pressure at the sensor and can shift the reading. ## Key terms - [Calibration gas](https://www.sarveshanalytics.com/learn/glossary.html#t-calibration-gas) - [Vent](https://www.sarveshanalytics.com/learn/glossary.html#t-vent) - [Drain](https://www.sarveshanalytics.com/learn/glossary.html#t-drain) - [Blowback](https://www.sarveshanalytics.com/learn/glossary.html#t-blowback) ## Frequently asked questions **What power does an analyser need?** Check the model datasheet for voltage and consumption; use a clean supply. **Do I need instrument air for every analyser?** Only for functions such as blowback or air purges, and for some probes. **Where do I store calibration cylinders?** In a ventilated, secured place, with cylinders restrained, away from heat and incompatible gases. **Can I vent to the room?** Only if the sample is harmless in the quantity vented; follow your site safety rules. ## Related products [ ### ACCURRA-S Online analyser for trace, percent and purity O2, CO, CO2, CH4 and dew point; can measure two gases from one sample. View ACCURRA-S ](https://www.sarveshanalytics.com/safe-gas-analyser.html)[ ### i-Cons Smart Peltier sample conditioner with diagnostics, auto blowback and Modbus, in a compact 19 inch cabinet. View i-Cons ](https://www.sarveshanalytics.com/smart-systems-for-gas-analyser.html) ## Where this applies - [Gas purity certification and cylinder filling](https://www.sarveshanalytics.com/applications/gas-purity-certification-and-cylinder-filling.html)