Commercial ice machine leaking water
A commercial ice machine moves a lot of water: it fills, freezes, dumps the leftover water every cycle, and drains the melt from the bin. Most leaks are that water going somewhere other than the drain, and most of them start with how the machine was installed.
Water on a kitchen floor is a slip hazard, and water near an ice machine is near mains electricity. Mop it up straight away. If water is pooling in the bin and won't drain, Hoshizaki's instruction is to turn the machine off and close the water supply valve, then call for service.
Find where the water is coming from
| Where you see water | Most likely cause |
|---|---|
| Under or behind the machine, near the drain | A drain line that is blocked, undersized, not sloped, or overflowing the floor drain |
| Standing water in the ice bin | A blocked bin drain |
| Running down the front, or over the edge of the bin | The machine isn't level, or the bin is overfilling |
| Dripping from inside the ice-making section | Water splashing past the curtain, or a trough overflowing |
| Water running even when the machine is off | The water inlet valve isn't closing |
| Beads of water on the outside of pipes and panels | Condensation, not a leak |
1. The drains: the most common cause
Every harvest cycle, a cube machine dumps the water it didn't freeze, and the bin drains the melt continuously. If the drain can't take it, it backs up and overflows. Hoshizaki's KM installation manual sets out what a drain needs:
- A fall of 1/4 inch per foot on horizontal runs.
- A vented tee for proper flow.
- Separate lines for the ice maker, the bin, and a water-cooled condenser if there is one.
- At least 3/4 inch inside diameter, in hard pipe.
- A 2-inch air gap between the end of each drain pipe and the floor drain, and never piped directly into the sewer.
Manitowoc's specification is similar: a drop of 1.5 inches per 5 feet, with no traps in the line, and a floor drain big enough for all the drains feeding it. It also explains the air gap: a direct connection lets bacteria from the drain line contaminate the ice machine.
A drain line that sags, kinks, runs uphill, or was teed into another drain will eventually back up. Grease or scale in a shared floor drain does the same. If the floor drain itself is slow, the problem may not be the ice machine at all.
2. Water standing in the bin
Ice melts constantly in the bin and has to drain away. If water collects in the bottom, the bin drain is blocked — often by debris, scale or slime at the drain opening. Clear the opening and flush the line. If it still won't drain, follow Hoshizaki's instruction: machine off, water off, call for service.
3. The machine or bin isn't level
Hoshizaki is direct about it: "An out-of-level icemaker could result in improper operation, poor performance, water leaks, and/or damage to the icemaker." Its manual says to level the bin before fitting the ice maker on top, then check the ice maker is level afterwards. Manitowoc says the machine must be level side to side and front to back.
A machine that tilts forward sends water out of the front of the trough. Floors in kitchens are often sloped towards drains on purpose, so a machine set straight on the floor is often out of level. Put a spirit level on top and adjust the legs.
4. The bin is overfilling
On dispensers, Hoshizaki warns against setting the ice level above the recommended bin control setting: higher levels can cause the ice maker to move, water to leak, or ice to overflow. If ice is spilling or the machine keeps producing into a full bin, the bin control isn't stopping it. Hoshizaki boards show this as a 9-beep bin control check. See our Hoshizaki and not making ice guides for the bin sensors on each brand.
5. Splashing inside the machine
Water runs down the evaporator during the freeze cycle, and the water curtain keeps it from splashing into the bin or out of the machine. A curtain that is missing, hanging crooked, or not refitted properly after cleaning lets water spray. Manitowoc's manual notes that removing the curtain while the pump runs makes water spray out of the unit — the same thing happens when it isn't seated.
A distribution tube with blocked holes, from scale, can also send water sideways instead of down the evaporator. Descaling fixes that: see how to clean a commercial ice machine.
6. Trough overflowing
If the water trough overfills, it spills. On machines with a float, Manitowoc's troubleshooting says to check the float position and adjust the water level. A float jammed by scale does this; so does a water inlet valve that doesn't close fully, which keeps feeding water. Hoshizaki lists a water valve leaking by among the causes of its 3-beep long-freeze alarm, and a leaking valve shows up as water still trickling when the machine is switched off.
7. Condensation
Cold water lines and metal panels sweat in a humid room. That's water from the air, not from the machine. Hoshizaki's manual includes a separate condensation drain outlet for this reason. Its rated operating range is 45°F to 100°F ambient; a hot, steamy dish area at the top of that range will produce a lot of condensation.
Water pressure
Too much pressure can force water past valves and fittings. Hoshizaki's KM range takes 10 to 113 psi and requires a pressure-reducing valve above that; Manitowoc's CrystalCraft takes 20 to 80 psi. Water hammer — banging pipes when valves shut — is a plumbing problem Hoshizaki says must be fixed by a qualified plumber before the machine is installed.
When to call someone
- A plumber: drain slope, venting, air gaps, a slow floor drain, high pressure or water hammer.
- An ice machine technician: a water inlet valve that won't close, a float or bin control fault, or any leak from the refrigeration side.
Hoshizaki recommends installing ice machines in a contained area with a floor drain wherever water damage is a concern. If yours isn't, a leak tray under the machine is cheap insurance.