How long does a thermometer last?

pudgybunny

I have the same thermometer for daily temping I got about 9-10 years ago and changed the battery a couple of times. Seemed to be working fine but the last 3 days my temp was exactly the same. Not sure of what signs to look for to tell you it is reaching the end of it's life(and if that is one or not). Anyone know? I tried searching Google but no luck. Thanks for helping with my odd request!

Valancyy

Mine is 4 years old and I've never even changed the battery (but I only use it when TTC).

I agree with PP, do a few tests at different times of the day and see if it changes.