Maple/Chase Thermostat #09600. The copper negative battery conductor developed metal fatigue and broke off.
Now the 2 batteries are making intermittant connections and the thermostat
Shows a message that the batteries need replacing no matter many times I replace them. Finally got it to work by bending and inserting a paper clip to complete the circuit, but would prefer a more reliable fix. Any ideas?
Note: The batter connector terminals on the thermo develop corrosion over a time and have to be cleaned using emery cloth or a small file to allow current to flow. Be sure to check yours. After 20 years my #09600 thermo works fine, but MC
Support says they have no fix and to buy a new one. How Green! But also a tribute to the engineering and design for reliability, except for a very simple part!

Don't blame the manufacturer for not replacing for free, a cheap 20 year old part. Be glad you figured out how it could be jury rig it, so you could save up to eventually replace it with a new one. Probably wouldn't have failed had you just checked the batteries regularly.

Considering 20 years of bending the battery tabs to insert new batteries, not a bad deal. Get a new digital unit, cheap and work great.