Best Thermal Imaging Camera UK: Handheld Cameras For Trades

HIKMICRO B20 has a 256 x 192 thermal sensor, below 40mK sensitivity at 25°C and a 25Hz frame rate. HIKMICRO lists -20 to 550°C, accuracy of ±2°C or ±2% for ambient 15 to 35°C and objects above 0°C, a 3.2 inch screen, a 2MP visual camera, Thermal, Visual, Fusion and picture-in-picture modes and centre spot, hot spot and cold spot measurement. It lists about 6 hours of operation, IP54, a 2m drop test, about 380g, 16GB of memory and 2.4GHz Wi-Fi. The page says the figures are for reference and the product prevails.

FLIR C5 has a 160 x 120 sensor, thermal sensitivity below 70mK and a range of -20 to 400°C. FLIR lists accuracy of ±3°C from 0 to 100°C and ±3% above, a 5MP visual camera with a flashlight, 4 hours of operation, 2 hours to charge over USB-C, IP54 and a 2m drop test. Dimensions are 138 x 84 x 24mm. FLIR's copy mentions finding hot fuses, air leaks and plumbing issues. The page does not state a field of view or weight.

Bosch GTC 400 C (0 601 083 108) has a 160 x 120 sensor (19,200 measuring points), sensitivity of 50mK or lower, a 53° x 43° field of view and a minimum focus distance of 0.3m. Range is -10 to 400°C with ±3.0°C accuracy and 0.1°C resolution. It has a 3.5 inch display, memory for 500 images, IP53 protection and a weight of 0.54kg, and it runs on a Bosch 12V battery or four AA cells. Images move by Wi-Fi or MicroUSB to the Bosch ThermalOn app or GTC Transfer software. Bosch describes it as ideal for inspecting insulation, heating systems and heat flow and for finding overheated parts. The page gives no battery runtime.

Fluke TiS20+ has a 120 x 90 sensor (10,800 pixels), 60mK sensitivity, a 50° x 38° field of view and fixed focus with a 50cm minimum distance. Range is -20 to 150°C and accuracy is ±2°C or ±2% at 25°C, whichever is greater, for targets at or above 0°C. It has a 3.5 inch touchscreen, IP54, a 2m drop rating, Wi-Fi and Fluke Connect software, and weighs 0.72kg. Fluke lists 16 hours of continuous use without Wi-Fi. A separate TiS20+ MAX model is also listed. The page's frame rate line mentions 30Hz versions but both listed models are 9Hz.

• Fault finding on boards: a loose or overloaded connection runs hotter than its neighbours. Scan the board under load. The camera sees surfaces only, so the cover has to be off, which is work for a competent person following safe working practice. FLIR's page names hot fuses as an example.
• Heat loss: Bosch lists inspecting insulation and heat flow as an intended use. Scan walls, roofs and window reveals when the inside is warmer than the outside.
• Damp: wet material often reads cooler than dry. A camera finds the patch and a damp meter confirms it. See the damp meter guide.
• Underfloor heating: with the system running, a camera shows the pipe layout and any loop that is not warming. A wide field of view helps in a small room: Bosch lists 53° x 43° and Fluke 50° x 38°.

• Resolution: 120 x 90 to 256 x 192 across these four. Higher shows smaller faults from further away.
• Range: Fluke's tops out at 150°C, the others list 400°C or more. That matters for hot parts, not for walls.
• Sensitivity: lower mK shows smaller temperature differences, which helps with damp and heat loss.
• Minimum focus: Bosch lists 0.3m and Fluke 50cm, which decides how close you can get on a board.
• Visual image: FLIR and HIKMICRO list 5MP and 2MP visual cameras, for placing a hotspot on the real thing.
• Battery and storage: runtimes run from 4 to 16 hours across the pages, and Bosch gives none.
• Reporting: check the software for the report you send the customer.

For the rest of the electrician's kit, see the best damp meter, the best torque screwdriver and the best tool bag.