–Graha Kenkana building | Hitachi VRF project in Djakarta, Indonesia
VRF
The place: mixed-tenant office building suffers from an outdated cooling system
With a hot and humid tropical climate, cooling is one of Indonesia’s largest energy demands. On average, 50% to 60% of a commercial building’s electricity expenditure is used for air conditioning1.
Previously, the Graha Kencana building was using aging water-cooled packaged units which required dedicated air handling unit (AHU) rooms on each floor. This system was problematic for several reasons
- Poor energy efficiency, resulting in higher operations costs.
- Constant maintenance, spare parts were difficult to procure, and the water piping needed regular cleaning and repairs to leaks.
- Reliance on ozone-depleting R22 refrigerant, which had been increasing in price as it is being phased out in accordance with the Montreal Protocol.
- Noise disruption, as the AHU rooms were located on each floor, they disturbed adjacent occupants.
Planning for HVAC upgrade, the building owner required a reliable and durable system future-proofed to perform over the course of many years.
The solution: Hitachi VRF saves space, energy and maintenance costs
Switching from water-cooled units to a VRF system required significant retrofitting, but the high energy efficiency of Hitachi VRF has allowed the Graha Kencana to save on operational and maintenance costs well into the future, more than off-setting installation costs.
A combination of Side-Flow and Top-Flow compact outdoor units from the SET FREE range was selected for optimum performance and efficiency.
Top-Flow outdoor units were installed on the roof of the building, delivering air conditioning to major parts of the building. Side-Flow units were installed on the 2nd floor balcony, which connected to the ground floor indoor units. This flexible combination leveraged the building space to optimize the refrigerant piping layout, limiting the need for retrofitting work. For simplified and discreet integration, 46 of the 51 indoor units are ducted concealed types with high static pressure up to 180Pa.
“Since we installed the Hitachi Variable Refrigerant Flow system, the building’s annual electricity costs decreased by 20% to 30%. It was a smart investment!”
Gustaf Stevanus Rotinsulu, Graha Kencana Building Owner (2019)
For the Graha Kencana building, Hitachi VRF system provides:
- Energy Efficiency — by modulating the compressor speed and refrigerant flow in each outdoor unit, the system can adapt to fluctuations in energy demands (such as in meeting rooms which are busy at certain times of day), minimizing energy consumption.
- Reliability — Hitachi’s original Scroll Compressors are synonymous with superior reliability. As a leading pioneer of scroll compressor technology since 1983, Hitachi’s experience and expertise in manufacturing ensures excellent quality and durability.
- Free space —the use of outdoor units on the roof and balcony eliminated the need for AHU rooms on each floor, freeing up space for other uses. Additionally, the retrofitting work was done progressively over the weekends, minimizing disruption to building occupants during installation.
- Quiet Indoor Units — noisy AHU rooms have been replaced with discreet ducted units, with noise levels as low as 42dB(A).
Also beneficial from an environmental perspective, the switch from R22 refrigerant to R410A has eliminated ozone-depleting emissions.
1 https://www.business-sweden.se/globalassets/energy-sector-business-opportunies-in-indonesia-.pdf
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Location
Djakarta, Indonesia
Project
Retrofit
Date of installation
2018
Total System Capacity
346HP
Outdoor Units
Units-Top-Flow, Heat Pump type 44 HP - Side-Flow, Cooling-only type 20 HP
Indoor Units
Ducted High External Static Pressure 16 x RPI-FSNQ - Ducted High External Static Pressure 30 x RPI-FSNQH - Wall Hung 4 x RPK-FNQS
Centralized Controllers
Central Station PSC-A64S 7-Day Timer -PSC-1AT
