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Both chiller and VRF systems may be suited well to several applications respectively while each will have their benefits based on what the system is required to achieve . Driven on the demand for each type , major manufacturers and suppliers have developed their line-ups to accommodate both systems for different applications and designs they will cater to .
When you consider a chiller , it is common that association is made for these systems towards industrial scale or process cooling , while VRF has been associated mostly with comfort conditions . This is not quite an accurate association anymore given the development of these systems that have also been used in hybrid techniques ( making use of various technology / systems together ). Again , depending on the scale of the application , these systems may very well be relevant to either – based on technology advancements , for example a VRF system could be the correct choice for a small-scale industrial cooling application that makes a limited amount of specialised stock units and operates two hours a day .
Some of the benefits to consider of each system-type in a quick view could include :
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Chillers are more efficient at high-capacity loads such as what is required at a hospital with 24hr operation .
CHILLERS |
VRF |
Suited for larger capacity projects and large common areas . |
Beneficial for individual office temperature control . |
Most industrial / process cooling uses this system type . |
Various indoor units are available to suit the application – including hot water modules , fresh air units and air-air HR units . |
Has the benefit of free-cooling options – particularly useful during seasonal temperature fluctuations . |
Ease of power distribution and individual power consumption billing . |
Benefit of ease of humidity control and incorporating humidification on existing AHU and FAUs . |
No plant room required , and low ceiling void space required .
Studies indicate a 300mm reduction in duct size and 30 % space saving due to no vertical ducting required .
|
Plant rooms and central systems allow for maintenance without |
Less general maintenance is required . |
interrupting tenants . |
Air-conditioning to critical areas on back-up electrical power |
Chillers have a long life expectancy . Up to 30 years . |
is easier to control and avoid increased costs and capacity on |
generators or solar power . |
Individual components can be replaced easily . |
Simultaneous heating and cooling is possible . |
Tried and tested technology and well-known HVAC solution . |
Benefits from new technology and control methodology . |
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This table is by no means a full list of information and with each suggestion may come one , or many facts , to add relevance .
SITE PARAMETERS Some of the other considerations to take into account may be for example , looking at a project from the design concept stage and evaluating what you have to work with in terms of plant room space – is the building big enough to accommodate a centralised plant room and the associated equipment such as pumps and cooling towers , or , if pipe runs are easy or difficult , how will ducting affect the design , how long or high is the building , what sort of temperature control is required , how much of the building
RACA Journal I July 2022 or facility contains common areas , and of those common areas , how large is the void , and so on .
The questions for a retrofit or replacement project may consider different points too that will determine the choices of equipment to be made . Here for instance changing of an entire system may be needed for other reasons than meets the eye – a structure may not be able to accommodate any additional load or electricity supply may be limited or capped .
TECHNICAL EXPERTISE The available technical skills within a region may also be a factor when choosing the appropriate system , particularly when
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