Home heating and thermostat

typically hydronic systems like that need to be bled, start with the highest radiator, the bleed valve have a little square head and you need to have a key that fits them, most supply HVAC houses have them sitting on the counter but you can ask them for one.

You should not have the blower fan running if all thermostats are set as you say. You either have a relay problem in the air handler or the zone system wiring or controller is defective.

On the zone damper motor, there should be a little lever allowing you to open the damper for emergency heat. Probably a bad zone motor or connection.

Hello. Each zone in you home has one thermostat controlling one zone valve. Generally, when a thermostat is calling for heat the zone valve opens and the circulating pump comes on to move the water around that loop. If your other two zones are both working as they should and you now have a new zone valve on the third loop I would suspect that the thermostat is faulty. Regards, Joe

They will work, most zone controls only require the use of 1H/1C thermostats, the system stages and functions are controlled by the board itself.
http://customer.honeywell.com/TechLit/pdf/PackedLit/68-0237.pdf

because it dosent have a duct sensor - should not be a problem

Warm air rises and if the upstairs thermostat is on it will onerride to lower the temp upstairs. To have the dowstairs thermostat govern, the up stairs must be off . The whole house will balance to the controlling thermostat.

thats becaue you need more than this zone working like you said about the master/slave this zone is a slave.

Try changing the batteries.

Since you have three on/off timing modes could there be an overlap in the times?
The wires in the unit might be crossed. (don't always assume the contractor who wired maintained the correct colors , I have a friend who blew out a heating pipe because when a replacement motor valve was installed it was never wired right and the plumber assumed the colors were correct so no overtemp shutoff created steam in PVC pipes, OPPS)
There fore maybe one is still coming on. Do you have more than one heating zone? IF so see below

I guess the main question is why manually turn it off? why not use the program.

I will assume your heat is know as forced hot water heating. My house is multizoned however when the zone calling for heat turns off (zone valve closes) I installed a bypass valve in the lowest zone in the house, and reduced the circulator low shut off temp to 130 F which means even though the heat isn't on my circulator will continue to run dumping this excess heat in the lowest part of house to rise through house. (the spring loaded water valve allows the heated water to flow into this zone )We do have two thermistats. And even though the lowest one is not calling for heat the radiators are hot when the excess is dumped into this zone. So investigate and see if your system might be similar. (multizone).

Investigate your wiring, reprogram, replace any battery backup.