Wire-free Solar IAQ Controller
We have recently developed a very nifty and innovative product to monitor indoor air quality - the wire-free solar IAQ. A compact unit complete with highly efficient and reliable CO2, Temperature and Humidity sensors with set-point adjustments and a large display screen. The unit is totally portable, requiring no wires and no installation.
You can simply hang it or place it anywhere in your office areas. It does not require a power connection, as it comes with an efficient solar cell that harvests its own power from ambient interior lighting. It has a wire-free advanced application specific control for VAQ stations with easy integration.
An optional smoke detector can also be connected with this controller to provide early warning in case of fire and at the same time strategise and control VAQ stations, fire smoke dampers and other smoke exhaust systems using Intelligent Damper Control and Monitoring System.
Its astonishing features were acknowledged at ACREX 2014, the biggest industrial showing in India for HVAC industry. It was adjudged the best innovation in green product category.
Demand Controlled Ventilation for Car Parks
Traditionally CO is considered to be biggest threat in car parks, and NOx where there are heavy loads of diesel vehicles. CO levels typically should be maintained within 29 (25) mg/m^3 (ppm), with peak levels not to exceed 137 (115) mg/m^3 (ppm), as per NBC India. Whereas NOx should be maintained within 1 ppm, as per various building codes.
We realized that since CO2 is the main product of combustion, it is better to measure CO2 instead of measuring every toxic component which might occur occasionally. The measurement of CO2 , therefore provides a good measure of accumulated exhaust and air quality. It also can also be measured more precisely and reliably than any other toxic gas. With rapid development of environment friendly modern cars with catalytic converters generate 100-900 times CO2 as much CO. Therefore CO2 itself is a greater threat to safety and health of people present in car parks. Thus it was obvious that regulatory demands have not kept pace with requirements.
We therefore designed a demand control ventilation system for car parks. The unit includes CO &CO2 sensors integrated with a controller that solves two problems instead of one. First it affects energy saving by reducing ventilation rates during low movement of vehicles and second, it also triggers smoke exhaust in case of fire.
The product received a lot of attention and appreciation at the recent ACREX 2014. Naturally, it was adjudged the best innovative product in the indoor air quality category.
Biggest Leap in Demand Controlled Ventilation
We managed our biggest leap in demand controlled ventilation some time back. Traditionally VAV terminals were installed in supply air with a thermostat to provide temperature control, however now we are installing VAQ Stations with more accurate airflow measurement and control which comes with CO2, and rH sensors in addition to a thermostat.
Traditionally a pressure sensor with a controller was used to optimize air handler speed in variation to changing demand of VAV installed at supply air. Whereas now VAQ Stations are intelligent enough and communicate with each to optimize air handler speeds in advance rather than waiting for pressure variation in the duct.
So far one CO2 sensor at return air was used to control outdoor air, which was compromised with varied pattern of occupancies in multiple spaces (when various spaces are fed by a common air handler) resulting in under-ventilated and over-ventilated individual spaces.
Whereas now VAQ stations at supply air with CO2, and rH sensors communicate with VAQ stations at outdoor air and optimize outdoor air with help of a multiple space equation as mentioned in ASHRAE standard 62.1 and provide proper ventilation in each and every space.
In addition to the giant leap in providing best control system for demand controlled ventilation, this whole system can be integrated on third party BMS system for monitoring indoor air quality and outdoor air intake which is a prerequisite for green buildings.
We are thankful to our valued clients, and business associates for appreciating and using this award winning system ( awarded with best innovation in product design under indoor air quality at Acrex 2011).
VAQ-OA for Free Cooling and Optimised Ventilation
We have recently installed VAQ-OA to provide free cooling during low outdoor temperature and at the same time provide optimised ventilation rates for better indoor air quality.
It is installed in a set of two at outdoor, return, and exhaust air. With one sized for outdoor air intake and other sized for total supply air. Former uses a CO2 sensor as controlled variable and the latter uses Enthalpy as controlled variable.
Thus it provides appropriate intake of outdoor air with greater energy savings. We extend our sincere thanks to Mr. K V Suresh (principal HVAC consultant at Gherzi Eastern Ltd.) for designing and incorporating this system in his projects.