ICE SeriesRefrigeration System

Thermostatic Expansion Valve (TXV)

The thermostatic expansion valve meters the flow of refrigerant into the evaporator changing its state from a high-pressure liquid to a low-pressure liquid. This drop in pressure causes the refrigerant to cool. The cooled refrigerant absorbs heat from the water circulating over the evaporator. As the evaporator fills with liquid refrigerant, the evaporator becomes colder.

The flow of refrigerant into the evaporator is controlled by the temperature at the outlet of the evaporator. The expansion valve bulb, mounted to the top of the suction line, senses the evaporator outlet temperature causing the expansion valve to open or close. As ice forms on the evaporator, the temperature drops and the flow of refrigerant into the evaporator decreases, resulting in a drop in suction pressure.

The evaporator should become completely flooded (filled with liquid refrigerant) during the freeze cycle. A completely flooded evaporator will have a uniform freeze pattern (ice formation across the evaporator). A starved evaporator (not enough liquid refrigerant) will have poor or no ice formation at the top of the evaporator, and the tube(s) exiting the evaporator will not frost. All tubes should be within 10 degrees of each other and frosted approximately 5 minutes from the start of the freeze cycle.

An expansion valve that is restricted or not opening properly will starve the evaporator resulting in lower than normal suction pressure. A low refrigerant charge will also starve the evaporator and cause low suction and discharge pressures. If not sure of the amount of charge in the system, the refrigerant should be recovered and the correct charge be weighed in before a defective valve can be diagnosed.

If the evaporator is starved but the suction pressure is higher than normal, the TXV is not the problem; refer to the troubleshooting tree in section C. If the TXV sticks open or if the thermal bulb is not making good contact with the suction line, the flow of refrigerant into the evaporator will be too great and liquid refrigerant will flood the compressor. The suction pressure will remain higher than normal and the machine will remain in an extended freeze cycle. Ice will build evenly but will be very thick.

Symptom

Problem

Possible Remedy

Evaporator flooded but suction

1

TXV thermal bulb not making

1

Tighten bulb clamp and

pressure not dropping.

 

good contact with suction

 

insulate bulb.

Compressor has been checked

 

line or uninsulated

 

 

and appears to be good.

2

TXV bulb installed incorrect

2

Locate bulb on top of

Suction line at compressor may

 

 

 

suction line

be colder than normal

3

System overcharged

3

Recharge system

 

4

TXV stuck open

4

Replace TXV

Evaporator starved, no frost

1

Machine low on charge

1

Recover refrigerant

on line(s) exiting evaporator.

 

 

 

and weigh in proper

Suction pressure is low.

 

 

 

charge

See Evap. Diagram Pg.E4

2

TXV restricted or stuck

2

Replace TXV and

 

 

closed

 

drier

Continued Page E4

Page E3

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Ice-O-Matic ICE0250 Series installation manual Thermostatic Expansion Valve TXV, Symptom Problem Possible Remedy

ICE0250 Series specifications

The Ice-O-Matic ICE0250 Series is a high-performance, modular ice maker that has been designed specifically to meet the needs of commercial establishments. Known for its durability and efficiency, this series is ideal for restaurants, bars, and hotels requiring a consistent supply of quality ice. The unit produces up to 250 pounds of clear, cube ice per day, making it an excellent choice for businesses with moderate ice demands.

One of the standout features of the ICE0250 Series is its energy efficiency. The ice maker is designed with a focus on reducing energy consumption, enabling business owners to save on operational costs while still providing ample ice for their customers. The unit is ENERGY STAR certified, reflecting its compliance with energy efficiency guidelines set by the U.S. Environmental Protection Agency (EPA).

The ICE0250 model also incorporates a unique air filtration system that helps ensure an uninterrupted ice production cycle. This technology minimizes the impact of airborne dust and contaminants, which can significantly affect the quality and hygiene of the ice produced. The unit's heavy-duty construction is designed to withstand the rigors of commercial use, providing long-lasting performance.

Another key characteristic of the ICE0250 Series is its compact design, which allows it to fit seamlessly into various commercial kitchen settings. Despite its smaller footprint, the unit does not compromise on ice production capabilities. Additionally, its user-friendly controls simplify operation, making it easy for staff to manage the ice-making process effectively.

Maintenance is also straightforward with the Ice-O-Matic ICE0250 Series. It features a self-cleaning function that automatically flushes the system, helping to maintain optimal performance while reducing the frequency and complexity of manual cleanings. This feature can save valuable time for busy kitchen staff.

In conclusion, the Ice-O-Matic ICE0250 Series stands out as an efficient, durable, and reliable ice maker for commercial applications. With its energy-saving technologies, robust construction, and ease of maintenance, this ice maker is a top choice for businesses looking to deliver ice in a consistent and hygienic manner. Whether for serving refreshing beverages or creating exquisite culinary presentations, the ICE0250 ensures that ice production remains effortless and efficient.