I have Aube TH147P thermostats throughout my house. The downstairs is in slab hot water heat and runs on one zone. The upstairs has 3 zones with hot water baseboards and 1 zone with hot water in floor. All of the upstairs thermostats work while in the programmable mode AND when I override the programming and adjust the temperature manually. I only have heat - no AC or fans. However, the thermostat downstairs will only kick in if it's set manually - it won't work in programmable mode. I've changed the batteries and even switched the entire thermostat with one from upstairs knowing that it was working and still it the programming doesn't work. Any suggestions?