Our range of thermostatic expansion valves from DunAn Europe, are designed to regulate refrigerant flow in various systems, including refrigeration, air conditioning, heat pumps, and ice machines. These valves precisely control the superheat at the evaporator outlet using thermal sensing elements known as bulbs, and balance tubes, ensuring optimal performance. With applications across small, medium, and large-capacity systems, these valves are ideal for residential and commercial use. Available in customisable series, they deliver reliability and efficiency tailored to meet specific operational needs.
TEV's contain a temperature-sensitive fluid that expands or contracts in response to the refrigerant temperature. This pressure change controls the expansion valve, ensuring the proper amount of refrigerant enters the evaporator to maintain the desired superheat, optimising system efficiency and preventing compressor damage.
A Wide Range of TEV's to Cater to Diverse Applications & System Requirements
DunAn offers a wide range of thermostatic expansion valve (TEV) series to cater to diverse applications and system requirements. Different series are designed to handle varying refrigerant types, pressure ranges, capacities, and environmental conditions, ensuring compatibility with various refrigeration and air conditioning systems. By providing multiple options, DunAn addresses the needs of residential, commercial, and industrial markets, allowing for customised solutions that optimise performance, reliability, and energy efficiency in each unique application.
DunAn TEV Overview
External Equalisation
Enhanced variants of DunAn TEV's benefit from the inclusion of a pressure sensing external equalising connection that allows for more precise control of the refrigerant flow by balancing the pressure at the outlet of the evaporator. The external equalisation enhancement improves system reliability, reduces energy consumption, and enhances the longevity of the components by allowing the valve to better handle the refrigerant. Refer to models with E after their series identification.
Improved Superheat Control: The external equaliser helps to maintain more precise control over the superheat in the evaporator. It does this by measuring the pressure at the evaporator outlet rather than relying solely on the pressure in the valve's sensing bulb. This ensures that the valve adjusts more effectively to the actual refrigerant conditions within the system, leading to better overall performance.
Compensation for Pressure Variations: In systems with long or unevenly distributed refrigerant lines, the pressure at the outlet of the evaporator can fluctuate. An external equaliser compensates for these variations by taking pressure readings from a point further downstream, offering more consistent superheat control.
Efficiency in Larger or Complex Systems: In larger systems or those with multiple evaporators or complex piping layouts, the external equalisation helps prevent issues that can arise from pressure imbalances. This allows the TEV to perform more consistently across a range of operating conditions, which is especially beneficial in commercial and industrial applications.
Application & Capacity
- The TA series is generally designed for smaller to medium-sized systems, offering both fixed and adjustable superheat options. It is a versatile option commonly used in residential and light commercial refrigeration systems.
- The TI series, on the other hand, caters to larger commercial refrigeration systems, such as those in transportation and industrial applications. It offers a broader range of capacities and is designed to handle higher pressures.
- The TCCE series is positioned between the TA and TI series but is particularly optimised for commercial refrigeration systems, providing flexibility in refrigerant types (including R134a, R407C, R404A, and others). It offers a good balance of features for both medium and large systems, and its design focuses on energy efficiency and precise superheat regulation.
Construction
- The TA series includes external equalisation options and models with or without an inlet strainer, focusing on flexibility and easy integration into smaller systems.
- The TI series is more robust, designed for systems with higher pressures and larger capacities. It is often equipped with interchangeable orifice assemblies and various connection options (flared, soldered), making it adaptable for large-scale commercial setups.
- The TCCE series provides similar flexibility with features like soldered connections and external equalisation but is specifically built to optimise energy efficiency and offer greater precision in refrigerant flow control for medium to larger systems. It is also designed to handle a broader range of refrigerants and deliver reliable performance under varying load conditions.
Versatility with Refrigerants
The TEV thermostatic expansion valve is compatible with a wide range of refrigerants.This flexibility allows it to be used across different types of commercial refrigeration systems, making it a versatile choice for systems that may require different refrigerants.
- TheTCCE series is applicable with the following refrigerants: R134a, R407C, R404A, R410A, and R290. depending on the application.
- The TA series is applicable with the following refrigerants: R134a、R404A、R407C、R22、R290、R448A and R449A.
- The TI series is applicable with the following refrigerants: R134a,R404A,R407C,R448A,R449A,R22, R410A and R507.
Bleed Functionality
The bleed function is an optional feature found on certain DunAn valve models, primarily those designed for systems where stable refrigerant flow and superheat control are crucial, particularly under fluctuating loads or short cycle conditions.
The bleed function allows a small amount of refrigerant to flow continuously through the valve, even when it's not fully open, to maintain smoother operation and prevent issues like hunting, or rapid opening and closing of the valve. However, some TEVs, especially in simpler or less complex systems, may not include this feature.
TEVs with the bleed function are typically designed for more sophisticated or demanding applications, such as larger commercial systems, heat pumps, or systems that experience variable loads. These valves ensure better stability and performance in such conditions. On the other hand, for smaller or more straightforward systems, a valve without a bleed may be sufficient.
DunAns TCE and TCBE valves have an enhanced bleed function. While others are available on request - contact our team to discuss the best options for your system.
Flow Path Design
The flow path design refers to the configuration of the valve's flow path, where the refrigerant flows through the valve at an angle or in a straight line.
A straightway design in a thermostatic expansion valve (TEV) is wherethe refrigerant flows straight through the valve body, with minimal changes in direction. This contrasts with other designs that might include multiple bends or turns in the flow path.
An angleway design in a thermostatic expansion valve (TEV) is where the refrigerant flows through the valve at an angle rather than in a straight line. This type of design typically results in a flow path that is angled to the valve body, often around 90 degrees.
A straightway design is often found in higher-capacity or more complex systems, such as commercial refrigeration, where precision and low resistance to flow are particularly important. However, not all TEVs feature a straightway design, as angleway designs may be better suited for specific applications or system types where space is limited, or when flow rates are higher.
Improved Super Heat Control for Better Efficiency, Performance & Protection
For proper system performance, the amount of superheat must be carefully controlled, which is where devices like thermostatic expansion valves (TEVs) or electronic expansion valves (EEVs) come in. These devices regulate the flow of refrigerant to maintain the correct superheat level ensuring core components receive the refrigerant in the right state for optimal performance and to prevent damage. They do this by measuring the temperature of the refrigerant vapour and adjusting the amount entering the evaporator for system protection and efficiency.
Refrigeration Line Components Overview
TA & TAE Series
For Small to Medium Systems
The TA series offers both fixed and adjustable superheat options for small to medium HVACR applications. The valves are compatible with a variety of refrigerants, including R134a, R404A, R507, R290, and R407C, making them suitable for different refrigerant types across various applications
The TAE benefits from the inclusion of an external equalising connection that allows for more precise control of the refrigerant flow by balancing the pressure at the outlet of the evaporator. External equalisation helps to maintain consistent superheat control, particularly in systems with fluctuating or uneven refrigerant flow, ensuring more stable and efficient performance.
Fixed Angleway
Adjustable Straightway
With or Without Bleed
With or Without Equalisation
Charge Options
TA Technical Data
TA & TAE Series
Contact our team on 01782 618 444 for availability and costs.
MOP Options
| Refrigerant | Range N -40°C ~ +10°C | Range HP -25°C ~ +20°C MOP +25°C | Range K -25°C ~ +10°C MOP +15°C | Range AC -25°C ~ +15°C MOP +20°C |
| R134a | (Without MOP) | 5.6 bar | 3.9 bar | 4.7 bar |
| R404A/R507 | (Without MOP) | 11.4 bar | 8.3 bar | 9.9 bar |
| R290 | (Without MOP) | 8.51 bar | 6.3 bar | 7.4 bar |
| R407C | (Without MOP) | 9.2 bar | 6.6 bar | 7.8 bar |
Nominal Capacity
| Model | R134a | R407C | R404A/R507 | R290 | R448A/449A | |||||
| TR | kW | TR | kW | TR | kW | TR | kW | TR | kW | |
| TA/TAE 0 | 0.11 | 0.4 | 0.16 | 0.5 | 0.11 | 0.38 | 0.17 | 0.6 | 0.15 | 0.5 |
| TA/TAE 1 | 0.25 | 0.9 | 0.3 | 1.1 | 0.21 | 0.7 | 0.32 | 1.2 | 0.3 | 1.0 |
| TA/TAE 2 | 0.5 | 1.8 | 0.8 | 2.7 | 0.45 | 1.6 | 0.74 | 2.6 | 0.7 | 2.5 |
| TA/TAE 3 | 0.78 | 2.7 | 1.1 | 3.8 | 0.6 | 2.1 | 1.1 | 3.9 | 1.0 | 3.5 |
| TA/TAE 4 | 1.3 | 4.6 | 1.6 | 5.6 | 1.2 | 4.2 | 1.6 | 5.6 | 1.5 | 5.2 |
| TA/TAE 5 | 1.9 | 6.7 | 2.5 | 8.6 | 1.7 | 6.0 | 2.4 | 8.4 | 2.3 | 8.0 |
| TA/TAE 6 | 2.5 | 8.6 | 3.2 | 11.3 | 2.2 | 7.7 | 3.2 | 11.2 | 3.0 | 10.5 |
| TA/TAE 7 | 3.0 | 10.5 | 4.9 | 16.7 | 2.6 | 9.1 | 4.7 | 16.5 | 4.5 | 15.5 |
TI & TIE Series
For Larger Scale Industrial HVACR Systems
While the core function remains the same as the TA series, regulating refrigerant flow through the evaporator by controlling the superheat, the TI series is often used for larger-scale commercial refrigeration and air conditioning applications, such as in transportation or water chillers. The TI series features interchangeable orifice assemblies, allowing for better customisation based on capacity requirements. It also offers options for both flare and solder connections and is designed with the flexibility to handle higher-pressure systems.
TIE benefits from the inclusion of an external equalising connection.
The TI series is suitable for refrigerants like R22, R134a, R404A, and others, offering robust performance in various demanding environments.
Available with MOP
Interchangeable Orifice
Flare and Solder Connections
Bi-Flow Options
TI Technical Data
TI & TIE Series
Contact our team on 01782 618 444 for availability and costs.
MOP Options
| Refrigerant | Range N -40°C ~ +10°C |
| MOP +15°C | |
| R22/R407C | 6.9 bar |
| R404A/R507 | 8.3 bar |
| R407C | 6.6 bar |
| R134a | 3.8 bar |
| R410A | 11.5 bar |
Nominal Capacity
| Orifice No. | R407C | R134a | R404A/R507 | R410A | R448A/449A | |||||
| kW | TR | kW | TR | kW | TR | kW | TR | kW | TR | |
| 0X | 0.96 | 0.27 | 0.68 | 0.19 | 0.65 | 0.18 | 1.05 | 0.29 | 0.87 | 0.25 |
| 00 | 1.87 | 0.53 | 1.2 | 0.34 | 1.3 | 0.37 | 2.08 | 0.6 | 1.67 | 0.5 |
| 01 | 3.67 | 1.04 | 2.08 | 0.59 | 2.64 | 0.75 | 4.07 | 1.16 | 3.43 | 0.95 |
| 02 | 4.96 | 1.41 | 2.55 | 0.73 | 3.7 | 1.05 | 5.52 | 1.57 | 4.60 | 1.3 |
| 03 | 8.45 | 2.4 | 4.30 | 1.22 | 6.29 | 1.79 | 9.37 | 2.66 | 7.92 | 2.29 |
| 04 | 12.9 | 3.67 | 6.40 | 1.82 | 9.97 | 2.83 | 14.27 | 4.04 | 12.05 | 3.5 |
| 05 | 17.1 | 4.86 | 8.43 | 2.4 | 13.1 | 3.71 | 19.66 | 5.57 | 15.7 | 4.5 |
| 06 | 20.5 | 5.82 | 10.1 | 2.87 | 15.6 | 4.42 | 23.05 | 6.55 | 19.05 | 5.5 |
TCCESeries
Medium to Large HVACR Systems
The TCCE series from DunAn is a high-performance thermostatic expansion valve designed for use in commercial refrigeration systems. Optimised for various refrigerants, including R134a, R407C, R404A, R410A, and R290, it offers reliable control over refrigerant flow to maintain efficient operation across a range of temperatures and conditions.
This series is known widely in the HVACR sector for its robust construction and precise regulation of superheating, ensuring optimal system performance and energy efficiency. TCCE valves are available in multiple orifice sizes and configurations, allowing for versatile application in different refrigeration systems. Options for soldered connections and external equalisation, which further enhance their adaptability and performance.
Compact Size
Fixed & Adjustable Superheat
Straight Flow Channel Structure
With or Without Check Valves
TCCE Technical Data
TCCE Series
Contact our team on 01782 618 444 for availability and costs.
MOP Options
| Refrigerant | Range N -40°C ~ +10°C | Range K -25°C ~ +20°C MOP 25°C |
| R404A/R507 | (Without MOP) | 11.4 bar |
| R407C | (Without MOP) | 9.2 bar |
| R134a | (Without MOP) | 5.6 bar |
| R410A | (Without MOP) | 15.6 bar |
Nominal Capacity
| Model | Orifice No. | R407C | R410A | R134a | R404A/R507 | R290 | |||||
| kW | TR | kW | TR | kW | TR | kW | TR | kW | TR | ||
| TCCE | 1 | 5.3 | 1.5 | 7.0 | 2.0 | 4.6 | 1.3 | 4.2 | 1.2 | 6.3 | 1.8 |
| 2 | 7 | 2.0 | 8.8 | 2.5 | 5.6 | 1.6 | 5.6 | 1.6 | 7.7 | 2.2 | |
| 3 | 8 | 2.3 | 10.5 | 3.0 | 7.0 | 2.0 | 6.7 | 1.9 | 9.1 | 2.6 | |
| 4 | 9.5 | 2.7 | 12.3 | 3.5 | 8.1 | 2.3 | 7.7 | 2.2 | 10.9 | 3.1 | |
| 5 | 11 | 3.1 | 14.0 | 4.0 | 9.1 | 2.6 | 8.8 | 2.5 | 12.3 | 3.5 | |
| 6 | 13.3 | 3.8 | 17.5 | 5.0 | 11.5 | 3.3 | 10.9 | 3.1 | 15.4 | 4.4 | |
| 7 | 16.1 | 4.6 | 21.0 | 6.0 | 13.7 | 3.9 | 13.0 | 3.7 | 18.6 | 5.3 | |
| 8 | 18.9 | 5.4 | 24.5 | 7.0 | 16.1 | 4.6 | 15.1 | 4.3 | 21.4 | 6.1 | |
TCE & TCBE Series
Bi-Flow Design Thermostatic Expansion Valves
TCE and TCBE valves differ from the TA or TI series mainly in their design optimisations for larger systems, offering features like a bi-flow function, which allows them to handle more complex refrigeration and heat pump cycles, as well as their suitability for commercial and large-scale applications.
Key features of the TCE/TCBE series include a straight-through flow design, adjustable superheat, and a bi-flow design, allowing them to be used in both cooling and heating modes. They also include a bleed function and are constructed with durable materials, including laser-welded power elements for long-lasting performance. The valves come with an external equalisation connection and can be configured with a Maximum Operating Pressure (MOP) setting.
TCE and TCBE valves are ideal for high-capacity, complex systems due to their enhanced durability and flexibility
Straightway Design
Bleed Function
The bleed function in the TCE and TCBE range of thermostatic expansion valves serves to improve the valve's stability and ensure better performance, especially during short or off-cycle periods. The bleed function allows a small amount of refrigerant to continuously flow through the valve, even when it's not fully open. This is crucial for the following reasons:
Preventing Hunting: The bleed function helps prevent "hunting" or the rapid opening and closing of the valve due to minor fluctuations in superheat. By allowing a small constant flow, the valve's operation becomes smoother and more stable, reducing the chances of erratic performance.
Maintaining Superheat Control: In certain conditions, especially in low-load or short scenarios, the valve may need to ensure a minimal refrigerant flow to maintain superheat control. The bleed function helps maintain the proper superheat by ensuring that some refrigerant continues to pass through the valve even when it's not fully activated.
Reducing Pressure Fluctuations: The small bleed flow helps reduce the impact of sudden pressure fluctuations in the system, which could otherwise lead to overshooting or under-shooting the desired refrigerant flow.
Bi-Flow Design
Adjustable Superheat
Available with MOP
MOP stands for Maximum Operating Pressure. It refers to the maximum pressure at which a thermostatic expansion valve (TEV) is designed to function safely. This pressure is critical for preventing over-pressurisation of the system, which could damage components or compromise the system's operation.
TCE and TCBE series valves can be configured to handle a specific maximum pressure limit that the system is designed to operate at. The MOP setting is used to ensure that the valve functions safely without exceeding the maximum pressure the system can tolerate,providing an additional layer of safety for the refrigeration or HVAC system
MOP is a key specification that helps maintain the reliability and safety of the system, ensuring that the valve operates within its design limits.
Example
For instance, in a refrigeration or air conditioning system, the MOP setting prevents the system from operating at unsafe pressures that could cause system failures, such as leaks or equipment damage. By offering valves with MOP configurations, manufacturers ensure that these valves are compatible with a wide range of system pressures, allowing for flexibility and safety in different operating conditions.
TCE/TCBE Technical Data
TCE/TCBE Series
Contact our team on 01782 618 444 for availability and costs.
MOP Options
| Refrigerant | Range N -40°C ~ +10°C | Range K -25°C ~ +10°C MOP 15°C |
| R404A/R507 | (Without MOP) | 8.3 bar |
| R407C | (Without MOP) | 6.6 bar |
| R134A | (Without MOP) | 3.9 bar |
| R410A | (Without MOP) | 11.4 bar |
| R22 | (Without MOP) | 6.9 bar |
| R32 | (Without MOP) | 11.8 bar |
| R290 | (Without MOP) | 6.3 bar |
Nominal Capacity
| Model | Orifice No. | R134a | R404A/R507 | R407C | R410A | R32 | R290 | R22 | |||||||
| kW | TR | kW | TR | kW | TR | kW | TR | kW | TR | kW | TR | kW | TR | ||
| TCE | 3.5 | 6 | 1.5 | 7 | 2 | 9 | 2.5 | 12 | 3.5 | 18 | 5 | 10 | 3 | 10 | 3 |
| 4.5 | 8 | 2.5 | 9 | 2.5 | 13 | 3.5 | 16 | 4.5 | 24 | 7 | 14 | 4 | 14 | 4 | |
| 6.5 | 12 | 3.5 | 14 | 4 | 19 | 5 | 24 | 6.5 | 35 | 10 | 19 | 5 | 20 | 6 | |
| 9 | 17 | 4.5 | 18 | 5 | 25 | 7 | 32 | 9 | 47 | 13 | 25 | 7 | 27 | 7.5 | |
| 11 | 20 | 5.5 | 21 | 6 | 30 | 8.5 | 37 | 11 | 54 | 15 | 32 | 9 | 32 | 9 | |
| 13 | 24 | 7 | 26 | 7.5 | 36 | 10 | 45 | 13 | 68 | 19 | 36 | 10 | 38 | 11 | |
| TCBE | 15 | 29 | 8 | 31 | 9 | 42 | 12 | 54 | 15 | 81 | 23 | 44 | 12 | 43 | 12 |
| 19 | 37 | 10 | 39 | 11 | 53 | 15 | 68 | 19 | 102 | 29 | 54 | 15 | 54 | 15 | |
| 23 | 44 | 12 | 45 | 13 | 62 | 18 | 79 | 23 | 120 | 34 | 63 | 18 | 63 | 18 | |
