Easier use, wider application - the all new TE5 – TE55

Friday, May 21, 2010

Experience and proven results in the Refrigeration industry, as well as listening to customer requirements and drawing on technical advances made with previous thermostatic expansion valve models, has allowed Danfoss to launch the range of new TE5 – TE55 TEV's which are now easier to use and cover a greater range of applications.

Chapter 1. Easier use, wider application - the all new TE5-TE55

Experience and proven results in the Refrigeration industry, as well as listening to customer requirements and drawing on technical advances made with previous thermostatic expansion valve models, has allowed Danfoss to launch the range of new TE5 - TE55 TEV's which are now easier to use and cover a greater range of applications. 

A valve that has improved performance and exceptional value, comparable to the current Danfoss range and which is on a superior level to those of competing products.

One of the very best advantages of this valve family is that the new range (valve body, orifice and element) match the present range. Simply put, this means that they can be mixed giving a smooth change over and no stocking problems. 

Please note: Special attention is required when replacing the orifice of a TE12 in a current installation. 

Benefits compared to the present TE range:

  • Better capacity range with the new orifice range - no gap, no overlap
  • Quick and reliable sensor mounting with the new cylindrical sensor and the new bulb strap
  • Minimal stock, also in the transition period - old and new parts match together
  • Stable and accurate superheat control
  • Stronger dual bellows element - longer lifetime
  • No charge migration
  • The new design improves MWP from 22 to 28 bar covering use with R404A and R507.

Extensive testing including field tests have clearly shown that systems fitted with the new TE5-TE55 have been able to work stably with much lower superheat settings offering not only improved efficiency of the system but also reducing considerably the danger of liquid getting into the suction line (liquid slugging) and no charge migration. 

For the devastating effects liquid slugging can have on a compressor please see the article "Why Compressors Fail". 

One field test was carried out on a chiller of approximately 2 x 180 kW for air conditioning a shopping centre. The system had screw compressors and tube heat exchangers. Due to liquid slugging at start up the contractor was required to re-set for higher superheat every time. The system was running at 10 to 12 K superheat with the continuous danger of liquid slugging, it was risky for the system, time consuming for the contractor and expensive for the owner with the low energy efficiency.

The existing competitor valve was replaced by a new TEZ55 with MOP +15°C, orifice 11 with factory setting. Upon restarting the system, water temperature was approximately 25°C but the measured superheat was only 10 to 11K and no liquid was present in the suction line. After reaching the final water temperature of 6°C, superheat was stable at 6 to 7K. 

Both the contractor and the owner were very pleased with the results, with the contractor commenting on the ease of setup and installation of the valve and of course the improved performance of the system. For the owner there were cost reductions due to improved efficiency. Having a 4K higher evaporating temperature gave 22% energy savings.

Features Benefits
Dual diaphragm in stainless steel Long lifetime – reduced service cost
Stainless steel element No corrosion
Dual sensor sealing 100% tight sealing – long lifetime
Strong stainless steel capillary tube No risk of breaking the tube
Laser welding Long lifetime
Bulb strap Easy and convenient mounting

Chapter 2. New orifice

All of the TE5 - TE55 components (valve body, orifice and element) are interchangeable, and for the valve bodies and elements the code numbers will remain the same. This is not the case for the orifices which have been redesigned to give better performance with no gaps or overlaps in the selections. In the table below we have new orifice with code number and capacity. It can also be seen that the Orifice number has been changed (0.5 to 13) giving a much better indication of the capacity covered. 

Next we can see that by introducing the new orifice it has become much easier to select the new valves and cover all applications in the range of 8 to 210kW (R404A).

Chapter 3. New bulb strap

There is also a new bulb strap which when used in conjunction with the new compact cylindrical bulb gives excellent heat transfer.

The improved performance, longer lifetime, ease of selection and ease of use of the new TE5 - TE55 expansion valve range give real benefits over our old range and those of our competitors.