Here is an energy saving solution…
Recent changes to legislation means that operators of HVAC chillers and refrigeration equipment should review their equipment and the availability of replacement condenser fans.
In the past few months, Excalibur have had several enquiries to supply replacement AC axial fans for air cooled chillers from end users unable to obtain direct replacement fans, or where the cost has become prohibitive.
We have advised each person that this is not unusual and that the situation is likely to get worse, with many fans no longer being manufactured, or only manufactured in short production runs.
Since 2017, all new condenser fan motors used on new chillers and condensers are required to meet the International Electrotechnical Commission (IEC) motor efficiency regulations and the Energy-related Products Directive 2015 (ErP). This has pushed manufacturers to look at the overall efficiency of fans and account for the entire fan, including the control electronics, motor, bell mouth and impeller and to define minimum efficiency requirements for the fans.
New Equipment manufacturers cannot use products that do not meet the regulations on new equipment but can continue to sell motors or fans that do not meet the regulations as spares to existing equipment.
Fan manufacturers and OEM’s have benefitted from the spares market at the expense of the end user by selling replacement parts at ridiculously high margins. In addition to these high costs imposed on the end user, the end user should avoid trying to repair motors, as rewinds further reduce efficiency.
If replacement fans are available, the end user should carefully consider the costs involved and if the fans will be available in the future, as there are alternative options. Improvements in fan and motor design means that the replacement of existing condenser fans with the latest EC fans will increase airflow through the condenser, while consuming less energy at lower noise levels.
For many clients, we have removed all the existing AC fans and replaced them with the latest design IE4 Super Premium EC fans which have built in speed controls making them perfect for HVAC applications.
With speed controls built into each motor, it allows all the fans on each circuit to operate together, modulating the speed to maintain accurate discharge pressure dependant on the cooling demand and ambient air temperature.
The benefit of specifying new fans which have increased airflow, allows a lower discharge pressure to be maintained, increasing compressor efficiency. Increased heat rejection also improves resilience and cooling capacity at high ambient temperatures, which overcomes a major issue in many buildings where poor chiller locations exist.
When you consider the CIBSE life time guidelines for HAVC equipment is 15-25 years, it makes retrofitting of EC Fans a viable option to re-life the chiller, achieving energy saving benefits greater than those of existing fans and controls.
Excalibur have been improving the performance of HVAC equipment for the past 20 years, successfully retrofitting EC Fans to chillers, dry coolers, condensers, evaporators and AHU’s in the UK for much of that time.
