Trane helps Hablis Hotel reduce operation cost with highly-efficient retrofit solutions

If chillers were retrofitted with VFD, considerable power saving could be achieved when the hotel ran the chillers under partial load conditions.

Trane has recently completed a retrofit project for The Hablis Hotel, a luxurious first-class business hotel located at the centre of Chennai, India. The existing Trane water-cooled chiller RTHD retrofitted with variable frequency drive (VFD) not only helps the hotel reduce the power consumption significantly, but the return on investment (ROI) has exceeded the customer’s expectation counting on highly efficient HVAC solution coupled with reliability and comfort. It is estimated that the operational savings for the hotel would be more than USD 20,000 per year. 

“We used to have a dedicated service team taking care of the old chiller equipment. Now, the team has been relieved from that since Trane’s new water-cooled chiller has been ready in place. We are very satisfied with the high energy-efficiency and reliability offered by Trane’s HVAC system. It greatly helps us improve the internal team’s working efficiency while significantly reducing our operation cost.” said Ranjith Kumar, Chief Engineer from the Hablis Hotel. 

“We really appreciate Trane team’s effort in executing this retrofit project. The team had high technical knowledge and result oriented thinking which helped us achieve significant energy saving in our existing plant room. We would like to thank the entire team from sales to services, including the logistics team, who helped us for time-to-time updates on all deliverables”, he added. 

Identified the problem during a service visit 

As early as 2011, Trane’s chillers were sold to The Hablis hotel. Two machines were provided with different capacities– 280TR and 170TR. Both machines can operate efficiently depending on the load requirement. The efficiency of a machine drops when equipment runs at 40-50 percent load conditions, so it is very important for the machine running at required load to maintain its efficiency. 

During a service visit in 2019, it was found that the ageing chillers running under partial load conditions had high power consumption. After further investigation, our consultant found the operators at the hotel were running these machines at 25 percent load in an attempt to reduce operational cost, which had resulted in frequent visits by technicians with high maintenance costs. 

Proposed Trane VFD retrofitting as the solution 

Trane India team visited the chief engineer of the hotel with a detailed log of the hourly readings and other parameters from the field chiller. The engineers from Hablis’ team and Trane worked together to evaluate the situation, looked at various options of system designs and aimed to come up with the best solution. 

After rounds of data analysis and mutual discussions, Trane’s consulting engineers proposed VFD solution to the customer as the best option and convinced them that if the chillers were retrofitted with VFD, the considerable power saving could be achieved when the hotel ran the chillers under partial load conditions. The Hablis team was impressed by the savings presented to them. Further to that, the India team also submitted the offer with ROI after several rounds of commercial and technical discussions. Finally, Trane successfully secured the order from the hotel. 

Tackled the challenges in installation 

Although the definitive solution was in place, there were some unexpected challenges in the actual installation for this retrofit program. The incoming cables were provided in bare condition (i.e. there was no hazard prevention plate between the operator and the panel), thus if there was any spark in the terminal joint it might lead to accidents. Therefore, our India team provided an additional acrylic sheet in front of the cabling. Besides, the proposed VFD machine was bigger than the compressor panel mounting which led to vibration in the chiller. However, it is critical that any new equipment should be operated at low sound levels. In response, the team provided additional clamps at the site to hold the AFD panel firmly to avoid vibration as there is no alternative option to expand the property to accommodate a chiller inside or out. 

The high energy efficiency and reliability offered by Trane’s HVAC system not only significantly reduces the hotel’s overall operation cost, but also helps to improve its internal working efficiency. In the appreciation letter from the hotel, it’s said that they would be happy to introduce Trane’s VFD offering to other customers of the hotel, and use this project as a leading example for future VFD retrofit projects.