How to size a commercial ice machine for peak service

Choose a commercial ice machine by checking two things together: how much ice it can produce in your working conditions, and how much usable ice will be ready before your busiest service. A large kg-per-day figure can still leave a bar short if the storage bin empties faster than the machine replenishes it.

For a pub, café or restaurant, start with your drinks menu and busiest trading periods. Then compare the exact machine's production figures, bin capacity and installation requirements. Here is a practical way to turn that information into a buying brief.

Production capacity and bin storage do different jobs

Production capacity, usually shown as kg/24h, describes ice made over time under stated test conditions. Bin capacity describes the quantity held ready for use. They are separate limits.

For example, Hoshizaki's UK specification for the IM-65PE lists 58 kg/24h at 10°C air and 10°C water, with a 26 kg storage bin. That does not mean 58 kg is waiting when staff open the door. The same sheet lists 53 kg/24h at 21°C air and 15°C water, falling to 43 kg/24h at 32°C air and 21°C water.

This is a specification example, not a statement of HERITS stock or a recommendation for every venue. Its value is showing why both numbers and their conditions matter.

Measure demand from the drinks you actually serve

If you already trade, record ice use across representative busy days. Note when bags are bought in, when the bin runs low and which service creates the pressure. An existing machine that runs out may be undersized, but poor performance or insufficient preparation time could also be involved.

For a new venue, build the estimate from expected sales. Make representative drinks using your intended glassware and ice format, weigh the ice used, then multiply by the number of drinks expected. Include ice used in cocktail shakers as well as the ice served in glasses. Account separately for kitchen use, displays, discarded ice and other demand.

Measure portions rather than adopting one universal kilograms-per-customer rule. A café selling a few iced coffees and a cocktail bar can have similar customer numbers but very different requirements.

Scotsman's sizing tool treats its results as suggestions and highlights growth, unusual uses and purchased ice when replacing an inadequate machine. Use that as a prompt to check your own operation, rather than treating a calculator result as a final specification.

Map the busiest service, not just the daily total

Write down how much ice is needed during each service and how long the machine has to recover between them. A concentrated two-hour rush creates a different storage requirement from the same demand spread over ten hours.

For an initial planning calculation:

Ice needed at the start of a peak = demand during the peak − expected production during it + your chosen reserve.

Use the expected output at relevant air and water temperatures. Dividing kg/24h by 24 gives a planning average, not a promise of equal production every hour: machines make ice in cycles, can stop when the bin is full and need time for cleaning and maintenance. Check the proposed setup with the supplier before relying on the result.

Worked example: a two-hour evening rush

The following figures are hypothetical planning assumptions, not measured venue data or a recommended universal allowance.

In this example, the machine needs 20 kg of usable ice available at the start. A published 20 kg bin rating would leave no allowance for differences between nominal capacity and the ice staff can actually retrieve. Confirm the working fill level and usable quantity; do not assume the nominal rating provides a comfortable margin.

Also test the recovery period. If the rush finishes with the planned 4 kg reserve, rebuilding to 20 kg needs another 16 kg. At the assumed average of 2 kg/hour, that takes eight hours with no further use or losses. A second busy service sooner than that would require a different plan. Finally, add up the whole day's demand: a bin cannot compensate indefinitely for insufficient daily production.

Compare machines at realistic temperatures

Ask for the exact model's performance table, including the expected warmer conditions at your site. A headline rating obtained in a cool test room may overstate what is available beside a hot kitchen during summer service. Compare competing machines at equivalent conditions wherever possible.

Check where cooling air enters and leaves the unit. A machine that physically slides beneath a counter may still be unsuitable if that position obstructs its ventilation or service access. Hoshizaki's current IM-series instructions give different clearances for different models, so a single gap rule should not be applied to every ice machine.

For wider equipment choices, see our commercial refrigeration buying guide. Keep the ice-machine calculation separate from general fridge or freezer capacity.

Check the installation and the actual machine

Before ordering, confirm the overall dimensions with legs or feet, door access, manufacturer clearances, electrical supply, water requirements and drainage arrangement. Ask whether the proposed location needs a drain pump and whether it is included. Have the installer assess water treatment against the exact ice-machine requirements.

When considering a used or refurbished machine, request the full model and data-plate details, cleaning and service information, and evidence of ice production under recorded conditions. The old catalogue rating alone does not establish the present output of that individual unit.

Include cleaning access and downtime in the plan. The manufacturer's instructions should govern the machine's cleaning and sanitising routine. Avoid choosing a position that makes those tasks impractical. Our kitchen installation and layout guide covers the broader services and access checks.

Send a clear ice-machine enquiry

Give the supplier your busiest day's estimated ice use, peak-service demand and duration, recovery time between rushes, required ice format, available space and site conditions. Include any existing machine's model and the extra bagged ice you currently need.

Ask for both the expected production and usable storage to be checked against that brief. Where a modular machine and separate bin are proposed, confirm their compatibility and the complete installed footprint.

Ready to compare options? Contact HERITS with your demand estimate, available dimensions and delivery postcode, or browse the ice-machine category. Confirm the individual machine's condition, current availability, included accessories and written terms before ordering.