Diagnosing the Commercial Ice Machine Diagnostics

Commercial Ice Machines Are Complex

Learn From Our Ice Machine Diagnostics Series

Great technicians have learned the power of excellent technical skills. Great technicians also see the power of observation. When it comes to ice machine diagnostics, asking questions during the observation process is a bonus. Asking questions is still the most effective technique of troubleshooting. Always assume that the ice machine is working correctly until proven otherwise. You have learned that the refrigeration components are highly reliable and that maintenance is usually the cause of up to 75% of all service difficulties. Do an excellent job of assessing the installation before beginning any disassembly.

Whatever you do, leave your refrigerant manifold gauges in your service truck. Ice machine diagnostics do not require the manifold gauges out-of-the-gate. The easiest way to do the most damage to an ice machine is by connecting the manifold gauges unless necessary to make repairs. It should be noticed that over the last five years, business owners have taken an intense interest in how their equipment operates. Business owners know that their equipment does not need refrigerant every time the service technician arrives at the site.

To many owners and managers, breaking out the manifold gauges are a strong indication of potentially being fleeced.

Upon arrival at the ice machine location:

Speak with the customer

Discussing the customer’s concerns before investigating the ice machine equipment is good practice. Find out what the customers are thinking and observing. Besides good customer relations, this is an excellent troubleshooting technique. Below are some sample questions that yield enormous information.

• What did the ice machine sound like when you noticed the problem? Sounds are considered sounds caused by regular operational sequences, whereas noises are deemed unusual sounds. Ask questions before undertaking any disassembly of the machine.
• Customers are accustomed to the sights and sounds of how their ice machines usually operate. If the ice machine suddenly begins making unusual noises, then the source of the current failure could be at the origin of the abnormal sound.
• When was the last time the ice machine had this or any problem? If the machine was recently serviced, then a previous servicing error could be the source of the problem since the ice machine was not repaired the first time correctly.
• When was the last time the ice machine was cleaned and sanitized? If the ice machine has not been cleaned in a long time, the first consideration should be directed to the water handling components, as they may be restricted or dirty. If the ice machine was recently cleaned and sanitized, then consider the possibility of incorrect reassembly.
• Is the customer satisfied with the condition and production of the ice? Is the ice visually clear and tasteless, and has it formed correctly? Has the ice machine been keeping up with the consumption demands?

Look and observe

Continue listening for both normal and abnormal sounds while the equipment operates. Observe the expected operation to determine if the machine is behaving according to the standard sequence of operation. Some other examples of irregular observations consist of the following:

• Is the ice machine operating? Is it switched on with source line power? Remember that the two most important things are line power and water availability. Check these first.
• Are there unusual accumulations of oily spots that could indicate a refrigerant leak?
• Are all of the cover panels in place to ensure condenser airflow as intended by design?
• Is the ambient condition hotter than the design specification? The ice in the storage bin might experience a high-than-average melting rate if the conditions surrounding it are abnormally hot.
• When at the condenser, observe that the compressor is operating appropriately as prescribed by the sequence of operation. This observation alone could precisely determine the first step in the diagnostic procedures. E.g., if the compressor is running during the head section off-cycle, you need to determine why that is occurring. Is it a stuck compressor contactor relay, or is the system correctly pumping down? It is possible that the pump-down solenoid is abnormally stuck open or leaking. Leaking solenoids are particularly of concern since they could result in short-cycling with the added wear and tear.
• If the ice machine water reservoir were not filled when it should be full, that would be a logical place to start the diagnostic procedure.
• Make the right investment of time and start first with the obvious choice. The first obvious choice is not always the actual failure, but it is still an excellent start instead of arbitrarily dismantling the ice machine.

Touch

All components of the ice machine have an expected temperature at which they are intended to operate. For example, lacking the correct evaporator temperature, the refrigeration effect cannot freeze the water making ice. Working knowledge of the expected sequence of operation is necessary before beginning this or any other diagnostics. Follows are example expectations of temperature when touching the example parts. These cases are given at the point of operation when the ice machine is in the freeze cycle.

• If the compressor shell is cool while operating, then that is likely abnormal.
• If the suction line is warm or hot, then that represents an obvious problem.
• If the discharge line is cool by touch, then that is also abnormal. Be careful when touching the discharge line, as it is usually scorching and can cause severe burns.
• If the suction line is not cold and the discharge line is not hot when expected, then the first logical step of the diagnostic procedure is to investigate the refrigeration section. Is it running? If the compressor is not operating at a point in the operation sequence, then start the diagnostics there.
• If the refrigeration components appear to be operating normally during the operation, then move to the water system. Is the reservoir full of water at the appropriate level? In the cube ice machine, is the water flowing smoothly and evenly over the evaporator?

There is no disassembly needed in this process other than removing specific panels to access, touch, and observe the active components.

Measure

After first determining the logical diagnostic steps needed. Select the appropriate tool to check for things such as voltage and refrigeration effect.

You may discover that the ice machine does not need repair. The technician must always consider the ice machine’s overall condition, such as if it needs to be cleaned and sanitized. Please don’t focus on any single thing as it leads to missing the obvious. As we have discussed, asking questions is a powerful tool to discover what others know. Good technicians investigate the installation and high-level operation before taking a screwdriver to the equipment. Taking things apart and trying to find the problem on your own might not address the customer’s initial concerns. Few things are more embarrassing than “fixing” something else while missing the problem described for the service call. The following questions and scenarios are designed to identify common areas that cause problems:

• Customers tend to postpone service calls until necessary and then at the last minute. Finding out when the problem initially occurred might save expensive troubleshooting and repair time. Customers are aware of how their equipment typically sounds. Has the ice machine made any strange noises? Strange unrecognized noises potentially indicate mechanical problems.
• Has the water and power supply been dependable, or has the location experienced a power or water supply failure? The water turned off for new construction or repairs, and power brownouts or outages due to construction or storms can severely affect the ice machine’s trouble-free operation. For example, without water, older equipment could freeze up and self-destruct due to water expansion. The Discovery of broken parts may not be the cause of the original service issue.
• Did the ice level in the storage bin decrease over the past few weeks or the last few days?

If the reduction occurred over an extended period, increased business operations might be the cause. For example, if the owner has run a special promotion, the ice machine may not keep up with the increased demand. The same condition is true if the owner has changed the drink or food offerings, unaware of the impact of ice consumption. A chain of restaurants starting a new beverage program not considering the production capacity of their ice machines is expected. Investigation of the ice machine operation would yield no operational defects because it is working correctly and as it always has. Compare the current ice production rates against the manufacturer’s literature’s anticipated production rates. A concise service report and analysis can be submitted to key personnel that likely won’t be debated by them by comparing the actual versus anticipated ice production. It is not possible to get more ice production than the rated capacity of the ice machine.

 Find Out More About Our Ice Machine Training Courses

If the decrease in production appeared suddenly, then a failure has probably occurred.

• Has the owner installed any new equipment recently? Perhaps a new water heater was connected, and the ice machine inadvertently has been piped to the hot water supply instead of the correct cold-water supply. In some circumstances, hot water could migrate into the cold-water line due to a check valve failure, permitting the infiltration of hot water. Check valves are standard in a modern commercial building to prevent this occurrence.
• Ask if the ambient heat load in the ice machine area has increased since (example) a new oven or dishwasher was installed. Any new equipment consuming electricity generates heat. By creating heat, the ambient heat load increases. This increased load negatively affects heat rejection from the air-cooled condenser while simultaneously increasing the heat load to the building air conditioning system. Ice production may circumstantially decrease, resulting in a ‘nuisance service call.’
• Has the ice machine ever meet the owner’s actual requirements? Has the system produced ice satisfactory to the business needs? If it has not, then consider a replacement machine is a better choice instead of investing in continued repairs of an ice machine that no longer meets the needs of the business.
• Ice machines operating in the winter temperatures did not need to meet the demands of summer temperature and increased resultant ice sales. Keeping up with ice demands in the wintertime may delay the owner from noticing that the ice machine is either undersized or operating with defects.
• Always do an ice production check before assuming that a problem has occurred. As discussed, the production check removes any room for doubt about the machine’s performance. It is impossible to get more ice production than the ice machine rated capacity; however, it is easy to lose production due to a dozen issues unrelated to the ice machine mechanics.
• Remember that the steps to understanding the problem or concern are to listen before acting.