Measuring and displaying oil boiler temperature

[ironer]

I'd like to fit an operating temperature indicator to the oil boiler. At the moment a mercury lab thermometer is puttied onto the outgoing (flow) pipe. It was one of those quick temporary fixes which became too permanent & it's now time to recover the said thermo.

Any suggestions for a permanent replacement please? A simple and cheap-ish solution would be ideal. Accuracy takes second place to readinngs being consistent as I could calibrate against the mercury thermo. An ideal solution would be a digital display showing both flow & return temperatures.

TIA

[Cicero]

================================ A range of sizes here:

two to monitor your system flow / return.

[Grimly Curmudgeon]

We were somewhere around Barstow, on the edge of the desert, when the drugs began to take hold. I remember "ironer" saying something like:

There's plenty of small cheap digital multimeters with a temp sensor input - just connect a type K thermocouple to the pipe. If you want something mains powered for constant readouts, look on ebay.

If it's only for a quick look from time to time, you could get a dual input digi thermometer (not that cheap) or simply use two cheap DVMs.