I have a Honeywell RTH230B that is less than 1 year old. We have it programmed as we'd like it to operate. It always let us change the programming by arrowing up or down to select the temporary heat setting. It kept that temporary heat setting for 2 hours and then went back to the regular progarmming. Since we changed the batteries, when we select a temporary setting, the unit doesn't go back to the correct programming until the next day. Any ideas?