I installed a Honeywell thermostat last year for our boiler and it worked perfectly. This year we were having issues with it not following the program schedule. The thermostat should be sleeping and then will turn on. I took the faceplate off and there is yellow goo inside on the components. Is this just a faulty thermostat or is something else going on? Honeywell has been no help when I have tried to contact them. Thanks!