Brannan Clip on pipe thermometer - Radiator Balancing Thermometer for Hot Water Pipes and Radiators

Excellent clip-on thermometer for pipes etc. Fiddly to hook on by spring but effective. Seems well made with clear dial with sensor about 12mm diameter. Sensor is flat so contacts only small area of 22mm pipe, so it's essential to use dollop of thermal paste as used for computer heat sinks etc. Thermometer then reads to within a couple of degrees centigrade. Very pleased with this instrument.

A bit difficult to get the spring to attach once I’ve the pipe, by hand. Otherwise ok and seems accurate.

Proved very useful to show my boiler reading was 15C higher than the water temperature really was. Seems to give consistent readings.A tip - fix one end of the spring permanently to the thermometer by bending the fitting with some pliers. It makes it so much easier to fit to larger pipes although you will still probably need some long nosed pliers to stretch the spring round the pipe.

The placement for the meter is on the stove flue just above the top of the stove. Presumably the assumption is that the temperature measurement on the flue pipe is directly related to the temperature in the firebox. Bear in mind that it is the firebox temperature you really want to control to minimise pollution and stove damage. Providing the relationship between the temperature measured on the flue and the actual temperature in the firebox is sound, then that's fine. But heat loses between firebox and flue will vary with stove design. This may well be enough for a crude measure but as for its accuracy you will never know. I have an inset stove and the flue pipe is not accessible. So I have to place the meter on the stove frame using the magnetic mount. The accuracy of my meter reading is therefore worse than if I had the meter on the flue as the latency between meter reading and firebox temperature is worse. But I do it anyway as it is the best shot I have. But as for its accuracy and pollution control who knows. It's about time stoves are required to have better temperature. measurement and control

It is easy to attach to the pipe and for my purposes to have a better idea of the boiler temperature. Assuming that the pipe temperature is correct then the boiler control knob is not very accurate. Would definitely recommend this product.

This thing is on it's third boiler return feed now. Having bought it to tune an old condensing boiler to better efficiency it came with us when we moved house. It then went on to an even older boiler till that expired. It's now on a brand new boiler and still an indispensable tool for fine tuning the lowest boiler settings possible while still heating the house.If you want to ensure your boiler is operating in condensing mode this is for you!

Easy to install on 22mm copper tube, but seams slow to react to temperature changes. I can’t comment on accuracy, the specs say that is + or - 4 degrees, I can only assume it works within the tolerance range. It appears to be well made for the price.

This product fell apart after 1 month of use.