Missing mash temps

[spunxter]

After 3 or so yrs using same mash tun only ever changing the braid im missing temps by like 8 or so degrees. Using same software many different recipes but sometimes same recipe. I notice no cracks inside and no water getting inside the middle either that i can tell. I preheat the tun with the same amount of water and temp each time. Im baffled. Anyone ever have to replace the tun after a few years?

 

[grampamark]

Have you tried a different thermometer?

 

[spunxter]

Yes i have

 

[bucketnative]

Have you checked the accuracy of both thermometers... a dense ice bath should be close to 0°C and boiling water should be close to 100°C, correcting for altitude if needed. Distilled/deionized is preferred water for this test.

 

[spunxter]

I will check them again just to make sure