--- title: "A Gas Smell Near an Ice Machine: Leave the Room First, Then Call From Outside" description: "Why many newer machines carry a small propane charge, the steps to take when you smell gas or hear a hiss, and the makers' house rules for the room around the…" url: "https://icemachinerepair.center/guides/flammable-refrigerant-and-what-to-do/" date_modified: "2026-09-26" --- Ice hygiene, water and gas # A Gas Smell Near an Ice Machine: Leave the Room First, Then Call From Outside A gas smell near an ice machine calls for the same first moves as any gas smell: no switches, no flame, open doors and windows, and get everyone out; call 911 from outside if the smell is strong. Newer self-contained machines may use R-290 propane, which EPA allows only in equipment built for it, and only trained technicians open that circuit. By [IceMachineRepair.center technical team](https://icemachinerepair.center/authors/technical-team/) Published September 26, 2026 ## At a glance. Many ice machines built in recent years cool with propane, sold as R-290, in a sealed circuit. It is a small charge and it stays put for the life of a healthy machine, but when anyone notices a gas smell or a steady hiss near one, the order of the next few minutes matters more than the diagnosis. Read the whole guide ### First move No switches, no flame, everyone out Call 911 from outside if the smell is strong. ### Which gas Read the nameplate Manitowoc lists up to 150 grams of R-290 on some models. ### EPA position Allowed in new machines designed for it With charge limits, ventilation rules, warnings and markings. ### Who repairs it Technicians trained for flammable gases Both Manitowoc and Scotsman say so in their manuals. In this guide 1. Why newer ice machines carry a flammable gas 2. What to do the moment you smell gas or hear a hiss 3. The smell may not come from the ice machine at all 4. What the makers' warnings ask of owners and staff 5. Who works on the sealed system, and how 6. Step by step 7. Questions ## Why newer ice machines carry a flammable gas Ice machines have moved to low global-warming gases, and for small self-contained units the common choice is propane. EPA's SNAP program lists R-290 as acceptable in new self-contained commercial ice machines subject to use conditions, and its 2024 rule ties those conditions to UL 60335-2-89 and ASHRAE 15, covering testing, charge size, ventilation, the space the machine is used in, and hazard warnings and markings on the unit. Manitowoc's manual for its flake and nugget machines puts numbers on it: models may hold up to 150 grams of R-290, and propane is flammable in air between roughly 2.1 and 9.5 percent by volume. A charge that small, in a sealed circuit that was built and tested for it, is not a hazard in daily use. It becomes one only when it escapes into a closed space that also holds a spark. ### How to tell which gas your machine uses The nameplate on the back or inside the front panel lists the gas and its charge; Manitowoc tells owners to check it there. Machines on R-290 also carry warning labels about the flammable gas, and Scotsman prints a flame warning at the very front of its manuals. Write the model, serial and gas type on a card now, so nobody has to go looking in an emergency. Source: [EPA — SNAP: Substitutes in Commercial Ice Machines](https://www.epa.gov/snap/substitutes-commercial-ice-machines) — R-290 is acceptable, subject to use conditions, in self-contained commercial ice machines; [EPA — SNAP Final Rule 26 fact sheet (May 2024)](https://www.epa.gov/system/files/documents/2024-05/snap-final-rule-26-factsheet.pdf) — R-290 only in new ice machines designed for it, consistent with ASHRAE 15-2022 and UL 60335-2-89, including charge sizes, ventilation, usage space, hazard warnings and markings; [Manitowoc — Flake and Nugget Ice Machines UFK, UNK, RFK, RNK: Installation, Operation and Maintenance Manual](https://www.manitowocice.com/asset/?id=uyhous) — Up to 150 g of R-290; flammable at about 2.1–9.5% in air; check the nameplate; no sharp tools on ice or frost; not in public corridors; only trained technicians and the maker's parts; disconnect power before service ## What to do the moment you smell gas or hear a hiss Treat a gas smell near an ice machine as a gas leak until someone qualified says otherwise. Switches, plugs and phones make small sparks, so the rule is to leave them alone in that room and act from outside it. - Do not switch lights, fans or the ice machine on or off, and do not unplug anything in the room. - Put out any flame and stop anyone from smoking or vaping; Scotsman warns against cigarettes, vapes and cellphones near the machine's pipes and cables. - Open doors and windows on the way out if they are within reach. - Get everyone out of the room, then out of the building if the smell is strong. - If the breaker panel is in another room, switch off that circuit there; never go back in to do it. - Call 911 from outside if the smell is strong, and the gas utility if the building has fuel gas. Source: [Scotsman — Installation and User's Manual, Cube Ice Machines with Storage CU0415X, CU0715X, CU0920X](https://www.scotsman-ice.com/service/User%20Manuals/17-3883-01.pdf) — R-290 flammable warning; no cigarettes, vapes or cellphones near pipes; no open flame, gas appliance or electric heater nearby; no flammable aerosols stored inside; ventilated room; qualified installer; rated recovery containers filled no more than 80% Close on an open back door of a restaurant storeroom with an ice machine inside, the room empty. ## The smell may not come from the ice machine at all Fuel gas piped to fryers, ovens and water heaters is odorized so leaks can be smelled. Propane used as a cooling gas is a purified product; when EPA first listed propane for this use in 2011, it said its rule neither required nor prohibited adding an odorant, and that its risk screen had assessed the gas without one. A leak from an ice machine's circuit may therefore give little or no smell. That cuts both ways. A rotten-egg smell in a bar with gas-fired equipment may be coming from that equipment's supply, not from the ice machine, and it still means leaving the room. A quiet leak from the ice machine, on the other hand, may show only as a hiss or as a machine that has stopped making ice. ### Sounds that belong to the cycle A working machine makes a rhythm of sounds: water running over the evaporator, a fan, a pause, then the rattle of cubes falling into the bin at each harvest. Those repeat and stop. None of them is a continuous hiss from one spot. ### Sounds that call for leaving the room A steady hiss or whistle from inside the cabinet that goes on between cycles, especially after a knock, a move or someone chipping at ice, is the sound to take seriously. Leave, follow the steps above, and describe the sound when you call. Source: [EPA — SNAP Rule 17, Federal Register, December 20, 2011](https://www.govinfo.gov/content/pkg/FR-2011-12-20/html/2011-32175.htm) — EPA's risk screen assessed hydrocarbon refrigerants without an odorant; the rule neither requires nor prohibits adding one ## What the makers' warnings ask of owners and staff The manuals for R-290 ice machines read like a short list of house rules, and most of them are about keeping a spark and a leak apart. They are easy to follow and cost nothing. ### House rules for a machine on R-290 - Keep open flames, operating gas appliances and electric heaters away from it, as Scotsman directs. - Never store aerosol cans with a flammable propellant in the bin. - Keep the room ventilated and the machine's vents and louvers clear. - Never chip ice or frost with a knife, pick or other sharp tool; Manitowoc forbids it because it can pierce the circuit. - Keep gasoline and other flammable vapors or liquids out of the area. - Do not place the machine in a corridor or hallway of a public building; Manitowoc's manual rules that out. ## Who works on the sealed system, and how Manitowoc allows only technicians with flammable-gas training, who understand high voltage and gas under pressure, to work on these machines, and it asks for replacement parts from the maker's own network. Scotsman says the installation must be carried out by a suitably qualified person, that non-original parts can be dangerous, and that decommissioning needs recovery containers rated for R-290 and filled no more than 80 percent. On a visit, the technician disconnects power before touching the circuit, checks for leaks with the right equipment, and repairs or recovers the gas using tools rated for it. A machine that lost its charge is not simply topped up: the leak is found and fixed first, or the repair-or-replace decision is made with the owner. Source: [Manitowoc — Flake and Nugget Ice Machines UFK, UNK, RFK, RNK: Installation, Operation and Maintenance Manual](https://www.manitowocice.com/asset/?id=uyhous) — Up to 150 g of R-290; flammable at about 2.1–9.5% in air; check the nameplate; no sharp tools on ice or frost; not in public corridors; only trained technicians and the maker's parts; disconnect power before service; [Scotsman — Installation and User's Manual, Cube Ice Machines with Storage CU0415X, CU0715X, CU0920X](https://www.scotsman-ice.com/service/User%20Manuals/17-3883-01.pdf) — R-290 flammable warning; no cigarettes, vapes or cellphones near pipes; no open flame, gas appliance or electric heater nearby; no flammable aerosols stored inside; ventilated room; qualified installer; rated recovery containers filled no more than 80% ## Where to stop An owner never opens, tightens, cuts or tries to patch any tube on an ice machine, and never runs a machine that hisses or smells of gas. Once the room has been declared safe, book a technician trained for flammable gases; do not switch the machine back on in the meantime. Written by [IceMachineRepair.center technical team](https://icemachinerepair.center/authors/technical-team/). Our ice machine technicians write these guides from their own service calls and each maker's published manuals. Sources: [EPA — SNAP: Substitutes in Commercial Ice Machines](https://www.epa.gov/snap/substitutes-commercial-ice-machines) · [EPA — SNAP Final Rule 26 fact sheet (May 2024)](https://www.epa.gov/system/files/documents/2024-05/snap-final-rule-26-factsheet.pdf) · [EPA — SNAP Rule 17, Federal Register, December 20, 2011](https://www.govinfo.gov/content/pkg/FR-2011-12-20/html/2011-32175.htm) · [Manitowoc — Flake and Nugget Ice Machines UFK, UNK, RFK, RNK: Installation, Operation and Maintenance Manual](https://www.manitowocice.com/asset/?id=uyhous) · [Scotsman — Installation and User's Manual, Cube Ice Machines with Storage CU0415X, CU0715X, CU0920X](https://www.scotsman-ice.com/service/User%20Manuals/17-3883-01.pdf) ## Step by step. Four steps, in the order worth doing them. 01 ### Leave switches alone Do not touch lights, plugs, phones or the machine's controls in the room. 02 ### Air and exit Open doors and windows on the way out and get everyone out of the room. 03 ### Power from outside Switch the circuit off only at a panel in another room. 04 ### Call from outside Call 911 if the smell is strong, and the gas utility if the building has fuel gas; book the ice machine visit once the room is cleared. For the heart of your home. ## Questions owners ask. ### Does an ice machine gas leak smell like rotten eggs? Not necessarily. The rotten-egg smell is added to fuel gas; propane made for cooling circuits may carry no odorant. A strong smell may point to another gas line nearby, and it still means leaving the room. ### Is it safe to keep an ice machine that runs on R-290? Yes, when it was built for that gas and is installed and serviced by the book. EPA allows R-290 only in new ice machines designed for it, with charge limits, warnings and markings. ### Can the sealed system on a propane ice machine be repaired? Often, by a technician trained for flammable gases using rated tools and the maker's parts. The leak must be found and fixed before any recharge. ### What if the ice machine hisses but there is no smell? Treat a steady hiss from inside the cabinet as a possible leak. Leave the room, avoid switches, cut the circuit from another room and call for service. ## The problems behind it. Each has a page of its own: what it usually means and the causes in the order worth checking. [All 17 problems](https://icemachinerepair.center/problems/) Clear the area first ### Hissing or a Gas Smell Near an Ice Machine on R-290 6 causes, cheapest first Problem ### Ice Machine Running but Not Making Ice 6 causes, cheapest first Clear the area first ### Burning or Hot Electrical Smell From an Ice Machine 6 causes, cheapest first ## When it needs a technician. The repairs on the right are where this guide ends when the checks do not settle it. ### Ice machine compressor and sealed system repair The compressor, its start parts and the sealed system, including machines on flammable R-290, tested for pressure and leaks and repaired by the maker's procedure. ### Ice machine diagnostic visit A visit that watches a freeze and a harvest, checks water, drain and condenser, reads stored codes, and names the part holding the ice back. ## More in ice hygiene, water and gas. Why ice is food and the bin must stay clean, what to do when water spreads across a floor or toward an outlet, and what a hiss or a gas smell means at a machine charged with flammable R-290. [The whole section](https://icemachinerepair.center/guides/safety-and-food/) Keeping the ice, the floor and the room safe ### Slime and Mold in an Ice Machine: Where It Grows, Why It Returns, What Cleaning Fixes The pink film on the bin door and the black specks on the curtain, what the FDA Food Code expects of an ice bin, and why room air and filters matter as much as sanitizer. Keeping the ice, the floor and the room safe ### An Ice Machine Leaking on a Busy Floor: Clear the Path, Close the Valve, Then Trace It People before puddles, the breaker from a dry spot, the hand valve by the machine, and how the timing of the water points to the drain, the supply or the bin door. Guides ### All 18 guides Six sections, by what you are trying to find out. --- **[Read on the site: A Gas Smell Near an Ice Machine: Leave the Room First, Then Call From Outside](https://icemachinerepair.center/guides/flammable-refrigerant-and-what-to-do/)** **[Book a visit with IceMachineRepair.center](https://icemachinerepair.center/schedule/)**