Engineering Superior Performance in Chillers
About the Client
Salarpuria Sattva is one of the top Real Estate Developers in India with several, iconic Tech parks, commercial complexes, and residential projects to their credit. MAVK is one of their preferred partners for undertaking AMC of HVAC Infrastructure in some of their Tech parks in Bangalore.
One such Techpark is Salarpuria Touchstone in Bellandur, Bangalore. This Tech park hosts several offices belonging to leading IT majors from around the world and has nearly 4000 employees working at the park.
Business Challenge
Touchstone is made of two Blocks – A and B, each having its own, independent HVAC circuitry. This includes air-cooled chillers placed on the terrace, with Ductable, Split and Cassette type ACs inside the offices.
The condenser coils used in the air-cooled chillers at Tower B of the Techpark are of the radiator type, made of aluminium.
Aluminium may be slightly less expensive than copper, but it’s not as sturdy as copper and also more prone to corrosion, breakages, and cracks. When such cracks and holes appear in the condenser coils, the refrigerant (gas) starts leaking and this affects the heat transfer and hence efficiency of the chillers. This is precisely what was happening at Touchstone. Further, the circuits were over 10 years old, which was more than the duration of what the aluminium, radiator type coils were originally designed for.
How We Helped
MAVK proposed replacing the existing condenser coils with copper-pipe type Condenser coils. Copper is more sturdy (more malleable and ductile), and thermally more efficient than aluminium, which is prone to uneven heating and cooling. Further, the brazing joints used in copper coils are also sturdier compared to the ones used for aluminium coils, making these coils safe for the refrigeration cycle. Further, when
replaced, these coils will work fine for the next 15-20 years, and in fact, prolong the life of your chillers.
Salarpuria’s management approved their proposal. In addition to the better RoI, the improved chiller efficiency also translates to better thermal comfort for employees at their tenant organizations. This was vital to the management as it complements their customer service motto.
Manufacturers of such coils were approached, and selected based on the quality of finish, customer testimonials, technology expertise and commercial proposal.
Between the 4th and 12th of January 2019, the existing coils were dismantled, new coils installed in place, then pressure tested using Nitrogen and finally commissioned. The project was supervised by Senior Managers from MAVK.
Once commissioned, this Chiller was turned ON and resumed normal working. On 7th March 2019, a Chiller Efficiency audit was done. The performance of this (working) chiller was compared to the backup chiller on the site, which had aluminium, radiator-type coils.
Results and Highlights
- The measured flow across this chiller was higher than that of the backup chiller.
- Because of the higher flow rate, the Delta T (ΔT) was low for the working chiller.
- The power consumption of the working chiller is the same as the rated power.
- Though both the chillers are of the same tonnage, the operating TR of the working chiller is higher than that of the backup chiller.
- With respect to SPC and COP (coefficient of performance), the performance of the working chiller, which has the new copper condenser coils is better than that of the backup chiller with aluminum, radiator-type condenser coils.