Blog Archives

Thermal Imaging for contractors – advantages in a nutshell

For contactors in the Building, Facilities Maintenance, HVAC, and Electrical industries, the ability to visualise each situation you are facing can make a huge difference. Knowing precisely where to start with a job, can save time and effort, meaning you increase efficiency, and ultimately provide a faster service to customers.

Those 20-30 minutes extra spent diagnosing each job soon add up, particularly at busy times of the year when you’ve got a waiting list. With that in mind, a valuable addition to many contractors toolkit is a thermal imaging camera.

But what specific applications is a thermal camera most useful for?

Below we summarise some of the best examples where thermal imaging has time and time again, proved an extremely effective diagnostic tool for contractors:


Heating and installation systems

  • Checking radiators for build-up of silt deposits
  • Identifying underfloor heating abnormalities

0560-8690_testo-869_04 underfloor-heating


Electrical Maintenance

  • Identifying overloads, imminent malfunctions or existing defects in switching cabinets and wiring

testo-872_0560-8721_08 overheating cable


Construction and Mould Assessment

  • Visualising thermal bridges in buildings
  • Detecting areas that are prone to mould

mould-risk-testo-limited testo-865_0560-8650_05


Leak Detection

  • Pinpointing thermal anomalies in leaking pipes
  • Locating roof leaks

testo-868_0560-8681_07 Floor_leak_example


Structural and Insulation Defects

  • Finding insulation defects
  • Checking air tightness of windows and doors

testo-868-871-872-house-with-scaleassist testo-872_0560-8721_07


Like some more information?

For more information on Thermography or any of please go to Alternatively, if you’ve got a requirement you’d like to discuss, you can contact us directly on +44 1420 544433 and we’ll be happy to help.

Testo Logo

Thermal Imaging – It’s all about the resolution

Not all thermal images are the same. If you are using thermography for example to detect leakages, cold bridges, mould or overheated components, the details matter. These elements, as well as many others, only become visible from a resolution of 160 x 120 pixels. Every pixel is a measuring point, therefore the higher the resolution, the more accurately you measure. And when you measure more accurately, you detect irregularities earlier, avoiding unnecessary damage for you or your customer.



Screen resolution is hugely important for all types of thermography


Another big advantage of using a camera with exceptional resolution is that thermal images can be taken at far greater distances, without affecting the image quality. In addition to this, low spec thermal images can be unclear, and often don’t provide a true or accurate reading. It is for these reasons that many only consider thermal imaging from a resolution of 160 x 120 pixels “real thermography”, with true value, rather than just a gimmick.

Thermal imaging is used in a number of industries, however in order to fully utilise this technology you first need make sure you’re using a quality camera. A good thermal camera should be a robust, quality tool which can be used for many day to day applications. Here are some examples where having the facility to take clear, crisp, non-intrusive thermal images is a huge advantage:


Checking heating installations

Whether pipes hidden under plaster, or leakages: With a thermal camera, you can non-intrusively make visible what you cannot see with the naked eye. You effortlessly visualise underfloor heating courses, and check the performance of a radiator at a glance. In these applications, a thermal sensitivity (NETD) of at least 100 mK is also important, in addition to the resolution.


blocked radiator 2

Using thermal imaging you can visualise heat distribution of radiators and heating systems


Inspecting switching cabinets

In switching cabinets, malfunctions are usually preceded by a temperature increase. With top-quality thermal camera you can not only measure this, but also visualise it. This can all be achieved precisely, without contact, and before it’s too late. The high-quality 160 x 120-pixel detector never misses an overheated contactor, an overloaded cable or an insufficiently tightened clamp.


testo-thermal-imaging-overheating cable

With a thermal camera you can pinpoint overheating cables immediately


Discovering building defects

Using thermal imaging you can discover and analyse cold bridges and sealing or insulation defects quicker and more efficiently than with any other tool. This results in the following advantages for you:

  1. Ensure building quality and can initiate preventive measures.
  2. Impress with the visual presentation of the quality of your work.



Thermal analysis is an efficient method of detecting structural defects


Identifying mould danger

High quality thermal imaging cameras calculate the humidity value of each measuring point from the externally determined ambient temperature, the air humidity, as well as the measured surface temperature. The humidity palette in the imager then uses the traffic light principle to represent the different risk zones:

Green = no risk

Amber = caution, mould formation possible

Red = mould danger



With thermal imaging you can outline areas at risk of damp before anything is visible to the naked eye


For more details on thermal imaging please visit our website or if you’ve got an enquiry you’d like to discuss, give us a call on 01420 544433 and we’ll be happy to help.

Testo Logo

The New testo 869 Thermal Camera – making top-quality thermography affordable

The testo 869 thermal imaging camera was developed in collaboration with experts from the heating industry, building trade, and facility management. It is perfect for detecting leaks, pinpointing thermal bridges or visualising overheated connections.

Combining high infrared performance, easy operation, and an unbeatable price, the new testo 869 makes high-quality thermography affordable for everyone. Built specifically for functions in a contractor’s daily job, its professional technology belongs in every toolbox.


The Testo 869 has been built specifically for contractors


Technical Highlights

  • High resolution for very good image quality: 19,220 temperature measurement points for precise and accurate measurement results – infrared resolution 160 x 120 pixels
  • Visualise small temperature differences: The thermal sensitivity is smaller than 120 mK
  • Focus-free 34° lens ensures a wide field of view, perfect to view the temperature distribution of measurement objects
  • Display of critical temperature conditions: automatic hot/cold spot recognition.
  • Pro software for easy image evaluation on the PC
  • Option to store thermal images in JPEG format


At only £799 it’s our best ever priced thermal camera, whilst still possessing testo quality


Key Applications

Thermal imaging can be used for a huge variety of tasks, across many different industries. From mechanical maintenance to checking freezer doors are correctly shut, the number of uses really is boundless. Here are just a few of the key applications thermal imaging is used for all over the world:


Detecting structural defects and ensuring construction quality

Analysis with a Testo thermal imager is a fast and efficient method of detecting possible structural defects. Furthermore, thermal cameras are ideal for providing proof of the quality and the correct implementation of construction measures. Any heat losses, humidity or areas of air permeability in a building will then be visible. The testo 869 makes it possible to detect faulty thermal insulation and structural damage – all using a non-contact method!

Typical applications:

  • Checking the air tightness of windows and doors
  • Finding insulation defects and thermal bridges in the building shell
  • Detecting and visualising areas that are prone to mould
  • Mapping underfloor heating systems



Thermal imaging is widely used to detect structural defects in buildings


Easy monitoring of heating and installation systems

Testo thermal imaging cameras are user friendly and easy to operate, so are ideal for quick checks of heating, ventilation and air conditioning systems. A quick glance is enough to discover irregularities in the temperature distribution. Thermography is the perfect solution for uncovering clogged radiators and leaks.

Typical applications:

  • Pinpointing the course of heating loops in an underfloor heating system
  • Checking radiators for the build-up of deposits
  • Measuring the supply and return temperature
  • Locating leaks



With a testo 869 you can see how well radiators are working or whether they need bleeding


Checking as part of electrical maintenance

With electrical installations or cables in general, increased temperatures are always an indication of an overload, an imminent malfunction or an existing defect. Using thermal imaging you can evaluate the heat status of low, medium and high-voltage systems. Thermographic images lead to the early detection of defective components or connections, so the necessary preventive measures can be introduced in a targeted way. This therefore minimises dangerous fire risks and prevents costly production downtimes.

Typical applications:

  • Checking switch cabinets
  • Checking electrical connections
  • Monitoring and checking photovoltaic system


Testo electrical thermal imaging

With a thermal camera you can locate the source of the problem without having to be intrusive


Want to find out more about the testo 869?

For more information on this fantastic offer visit: or give us a call on 01420 544433 and we’ll be happy to help.

Testo Logo

Safe maintenance of electrical systems using thermal imaging

Faulty electrical connections or overloaded switching systems in electrical distribution boxes, or electric drives can lead to costly production downtimes and even fire damage. Regular inspection of electrical installations and systems with a thermal camera significantly reduces the risk of such issues occurring. Using thermal imaging any abnormalities can be identified at a glance, meaning preventative measures can be taken immediately.


Electrical systems need to be operated with the greatest security possible


The challenge.

Roughly 70% of all weak spots in electrical systems can be traced to faulty clamp connections. This can be due to aging, incorrect installation, mechanical load or damage to the system components. Electrical energy then develops into heat, in some instances causing systems to overheat. This can have catastrophic consequences: Machines can break down, production lines come to a standstill, or system components have even been known to burst into flames.


testo-thermal-imaging-overheating cable

Ignoring even one overheating cable can have devastating repercussions


The solution.

Testo thermal imager models can be used on all electrical systems to localise faulty electrical connections, for discovering asymmetrical load distribution or for identifying overloaded conditions of any kind. They show the surface temperature distribution of electrical components at a glance. This allows weak spots to be identified early so faulty parts can be repaired or replaced before a breakdown can occur.



Thermal analysis is completely contactless, so normal activity doesn’t need to be disrupted


The great advantage of thermographic testing with a thermal camera is that technical systems can be examined without any contact whatsoever. The continuous operation of the system can be examined without disrupting any electrical systems which are currently in use. By regularly checking a system with a thermal camera, both downtime and the risk of fire will significantly decrease. The highest possible level of security is therefore guaranteed for both the people working with the system and the system itself.


overheating cable

With a testo thermal imaging camera you can pinpoint the issue in a matter of seconds


On the whole using thermal imaging lowers the maintenance and energy costs of any electrical system – by avoiding unexpected repair work and by optimising the quantities of energy used. Whether you wish to test transformers, electrical distribution boxes, switching systems or electric drives, a testo thermal camera is the perfect solution.


Want to discover more about thermal imaging?

For more information on testo thermal cameras or any testo products please visit our website: or give us a call on 01420 544433 and we’ll be happy to help.

Testo Logo

Choosing a Thermal Imaging Camera – What are my options?

There are a number of factors which come into account when choosing a thermal imaging camera, and not just the price. Depending on your individual application, somewhat careful selection is required to ensure the camera provides the neccessary features and is right for you.


Why invest in a thermal camera?

Thermal cameras are used in a number of industries, and often have many day to day uses within each specific profession. From heating engineers checking blocked pipes, to production engineers checking high end equipment is running smoothly, thermal cameras provide instant and contactless analysis, which no other technology can offer. Here are some of the main advantages:

Non-Intrusive – If you suspect a problem in for example pipework or underfloor heating, you can detect and locate the source of the issue immediately, without causing any damage



Why waste time digging around trying to find leaking pipes? With a thermal imaging camera you can locate leaks in a matter of seconds


Don’t let it become a problem – In many cases you can locate potential problems, before they become an issue

Show customers the issue – They provide the user with the facility to show customers the source of the problem immediately


Why choose testo?

Testo thermal cameras provide real value for engineers and professionals, and aren’t simply a gimmick you use once or twice. If that’s what you’re after then a testo camera might not be for you. What testo camera’s offer is a robust and quality tool which can be used for a number of day to day applications. The main advantages of testo thermal cameras include:


Undeniable quality – Testo cameras are far more robust and quality tools than lower quality alternatives

Higher image spec – this then equates to better image quality. You might not think this is that important but it really is. Low spec thermal images often provide unclear images, which don’t uncover the real issues



Testo cameras are designed to be used as tools, rather than just a gimmick


Free Super Resolution – All testo thermal imaging cameras now come with Free SuperResolution technology, so the resolution of all images is effectively doubled. This will make findings even clearer


The value of having a thermal camera at your disposal really is invaluable for many professionals. If you’re after something to take a thermal selfie and have laugh with you’re mates, then perhaps you should look elsewhere. But if you want to invest in a quality piece of equipment to add to your toolbox, then a testo thermal camera might just be for you.


Which Thermal Camera is best for me?

Deciding which camera is best suited to your requiremements can be difficult. Testo provide cameras ideal for smaller companies right through to large industrial applications. Below we have tried to summarise the features of the Testo range of infrared cameras and how they compare against each other.

If you would like full specifications on any testo camera please visit our website: If at any point you have a question about a camera and its capabilites please feel free to contact us on 01420 544433 and we’ll be happy to help.


testo-870-thermal-imaging-cameraTesto 870 – Thermal imaging camera

The testo 870 is our best ever value Thermal Imaging Camera. It combines quality with value to offer you the perfect entry level TI camera, at an affordable price. At under £1000, the testo 870 is the only thermal camera with a 120 x 160 pixel resolution, available for less than £1,000. It’s also the only camera in its class to offer automatic hot/cold spot recognition. In addition to this, testo 870’s now include SuperResolution technology as a standard feature. This effectively doubles the image resolution (so resolution increases to 240 x 360).

The 870-2 variant also has a built in digital camera, so a visual image is automatically taken and stored in parallel with the thermal image.


testo-875i-thermal-imaging-cameraTesto 875i – Thermal imaging camera

The T875i Series offer fantastic thermal sensitivity, an inbuilt digital camera, extended temperature range and laser pointer. It has a screen resolution of 160 x 120 pixels,(Super Resolution – increases res. to 320 x 240), sensitivity of NETD < 50 mK, measuring range of -30 to +350°C, Field of View of 32°. As with all our cameras this includes Free Super Resolution technology.



testo-882-thermal-imaging-cameraTesto 882 – Thermal imaging camera (high end)

The testo 882 Thermal Imaging Camera provides exceptional resolution as standard and is the ideal thermal imaging device for a number of applications. The already impressive standard resolution of 320 x 240 pixels can be further enhanced with the addition of testo SuperResolution Software giving your camera an output resolution of 640 x 480 pixels, providing crystal clear thermal images and indepth insight for a fantastic price.

You can carry out non-intrusive thermal inspections for building and industrial applications with the testo 882. The testo 882 in ergonomic pistol design, with 320 x 240 pixels, stands out thanks to even more precise infrared images. With 76,800 temperature measuring points, it sees every detail on the measured object. This makes it even easier for you to detect anomalies and weaknesses from greater distances.


testo-885-thermal-imaging-cameraTesto 885 – Thermal imaging camera (high end)

You can carry out non-intrusive thermal inspections for buildings and industrial applications with the testo 885-1. Thanks to the 320 x 240-pixel detector, in combination with the high-quality Germanium optics, the testo 885-1 achieves an excellent image quality. This allows weak spots and problems to be reliably detected. In combination with the Testo SuperResolution technology, the testo 885-1 records high-resolution thermal images in excellent quality (640 x 480 pixels) meaning all readings will incredibly accurate.



Testo 890 – Thermal imaging camera (high end)

The ultimate in precision thermal imaging. Thanks to the 640 x 480-pixel detector, in combination with the high-quality Germanium optics, the testo 890-1 achieves the highest level of image quality. In combination with the Testo SuperResolution technology, the testo 890-1 records extremely high-resolution images in megapixel quality (1280 x 960 pixels). This means that even the smallest or very distant measurement objects can be thermographed with an extremely high level of precision.


For more information on testo thermal cameras or any testo products please visit our website: or give us a call on 01420 544433

Testo Logo