T P Singh, Director & Country Manager, FLIR Systems
Thermal Imaging is gaining fast popularity among the proponents of non-destructive industrial tests. It has versatile advantages including cost saving, which perhaps is the topmost priority among the business runners today. T P Singh, Director & Country Manager, FLIR Systems takes through the applications and benefits of this technology in the field of HVACR during an interaction with Cooling India…
What is thermography and how it works?
Almost all objects around us emit infrared (IR) radiations which our eyes cannot see. Infrared thermography is the art of transforming an infrared image into a radiometric one; every pixel in a radiometric image is actually a temperature measurement, so temperature values to be read from the image. Thermal imaging cameras are the perfect tool for locating and identifying faults/failures because they make the invisible visible.
What are the unique advantages of this technology?
Infrared (IR) inspection is a powerful and non-invasive means of monitoring and diagnosing the condition of buildings. An IR camera can identify problems early, allowing them to be documented and corrected before becoming more serious and more costly to repair.
An infrared inspection within building diagnostics help:
• Visualize energy losses
• Detect missing or defective Insulation
• Find moisture in the insulation, in roof and walls, both internal and outside
• Detect mold and badly insulated areas
• Locate thermal bridges
• Locate leaks in flat roofs
• Source air leaks
• Detect breach on hot-water pipe
• Detect construction failures
• Locate radiant floor heating faults
• Monitor the drying of buildings
• Detect electrical faults
• Find faults in supply line and district heating
What are the application areas for this technology in buildings?
Detecting Poor Insulation and Air Leaks
Infrared thermography (thermal imaging) is an outstanding tool to locate building defects such as missing insulation, delaminating render, and condensation problems. Thermography also helps assess flat roofs for damaged insulation and trapped moisture.
The typical thickness of the insulation varies from country to country. In cold climates, the insulation usually is thick. In countries with warmer temperate climates, there is less thickness or nothing at all. On the other hand, in warmer climates, cooling inside is often used which calls for thick insulation to take care of the energy. Using an IR camera the rule of thumb is that it should be at least 10 °C temperature difference between outside and inside temperature the sides of the wall to get good, easy to see patterns. Using a camera with higher resolution and thermal sensitivity, the temperature difference can be less.
Detection of Air Leaks
It is not unusual to find air leaks through the envelope of a building. An air leak leads to higher energy consumption, often causing problems with the ventilation system, as well as causing condensation in the construction which makes the indoor climate poor. 90% of air leaks are caused by the defect in the climate shelf. To detect air leaks with an infrared camera a temperature difference and a pressure difference over the construction is needed. The air itself is not possible to see. With an infrared camera, however, you detect the characteristic patterns that occur when cold air is coming through a leak in the construction - goes along a surface and cools it down. The infrared inspection should always take place on the side of the construction with negative pressure.
Moisture damage is the most common form of deterioration for a house. Air leakage can cause condensation to form within walls, floors, or ceilings and wet insulation takes a long time to dry and becomes a prime location for molds and fungi. Scanning with an infrared camera can locate moisture that creates an environment conducive to molds - locations that may never be seen with the human eye. One might smell its presence, but not know where it is forming. An infrared survey will determine where inherently moist areas are located that promote potentially serious mold and health problems.
A thermal bridge is an area with less insulation due to the construction; such as a metal fastener, concrete beam, slab or column. Heat will flow the easiest path from the heated space to the outside - the path with least resistance. Very often heat will ‘short circuit’ through an element which has a much higher conductivity than surrounding material, which can be described as a thermal bridge.
Typical effects of thermal bridges are:
• Decreased interior surface temperatures; in the worst cases this can result condensation problems, particularly at corners.
• Significantly increased heat losses.
• Cold areas in buildings.
Supply Lines and District Heating
In cold climates heating of pavements and gangways are used. It is also common with district heating, a system for distributing heat generated in a centralized location for residential and commercial heating requirements. A thermographic survey can easily detect any defects in heating systems under ground. Even if there is snow on the ground, the heating pipe lines are visible with an infrared camera.
One of the most common faults in buildings is electrical faults.
What kind of experience or training is required to develop skill in working with this technology?
Basic half day training should be enough to start using the product. For expert applications, level 1 course is recommended which requires 40 hours that lasts for five days
FLIR co-operates with Infrared Training Center (ITC), an independent, ISO certified, worldwide training facility.
What are the latest models from FLIR that are available in India these days?
We have complete range of products. Starting from Innovative Clamp meter with IGM to a very sophisticated high resolution camera with more than seven lakh pixels. We have multiple options to choose from, based upon requirement/application. Models like C2, Ex-series, Exx series and T5xx series is available in start and mid segment. Range starts from INR 68000 plus tax.
What are your suggestions to the potential buyers from the HVACR industry?
The main message from my side will be to choose right product for your application. If the object is smaller and distance is longer, a good high resolution Thermal Camera is required for accurate measurement. The main technical name to choose a product keeping this requirement in mind is IFOV (Instantaneous Field of View). Choosing a wrong or low resolution product can be dangerous as it may not see potential problems and hence main purpose of using time, money, and energy can go waste.