Came down stairs yesterday and went to cut on air condtion and the thermostat was blank. went and check the one upstairs that one is working. went in basement snd hit the breaker nothing happen.

close ceiling vents
the hot air down stairs rises through the vents and adds to the upstairs heating
same as hot air goes up the stairs to the upper rooms

if there is no control of air movement between floors and you have it on cooling then any cold air will go down to the lower floor
or alternately if you have it set on heating all the hot air will rise to the upper floor
where is the system located (upstairs or down stairs ) and where is the thermostat located
to get control close any upstairs to down stairs doors or erect a heavy curtain across the stair well

With a two story house you have to be aware that cold air flows downwards so any cold air coming from an ac unit will flow downstairs( normally down the stairway) so unless you can close off the down stairs then the up stairs unit will be cooling downstairs as well. Ac units have a thermostat located in the air intake and it cools until the cold air has risen to that point. In effect the space above the ac unit will be hotter than the floor. Knowing how they work ,you can see that the upstairs unit will never reach the set temperature because the cold air is continually heating from the house and will never get to the top thermostat.
So your solutions are
1-- fit controls that restrict the cold air from leaving the upper floor (Doors)
2--don't run the upper ac unit unless you are living up there (waste of money
)3 place an ac in each upper room and keep the room door closed

Sounds like the programming on your thermostat needs to be reconfigured, but I need more information like the Honeywell Model number which can be found behind the front cove, but becareful to unsnap the t-stat properly not to damage the pins that connect t-stat to its base.

two things. 1 check the air vents on your radiators to make sure they are open to allow the steam in. Where is your thermostat in relation to the working radiators if the thermostat gets satisfied too quickly you won't have time to heat the other radiators. Steam rises and it is normal for upper radiators to get hot a little earlier

Ask for warranty If it is brand new.

This means the furnace is sending power to the thermostat. This can b anything from no 120v to furnace, blown low voltage fuse on furnace circuit board, condensate pump too full, transformer bad etc.

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.

There are a few things that can cause this problem. The most common is the hole behind the thermostat for the wiring was not covered up when the thermostat was installed. The thermostat will sense the air in the wall space or the basement if it is open to the back of the wall supporting the thermostat. Turn off the power to the air conditioner if attached and the furnace, remove the thermostat from the wall and seal up the wiring hole with duct tape. Insure the thermostat is mounted level when reinstalled. The thermostat should be mounted to sense the return air to the furnace, if the stair well leads upstairs, warm air rises, so keep the upstairs close to the same temperature as down stairs or move the thermostat and install a door to block air movement to the upstairs. There is a heat anticipator on the thermostat, the setting for it is in the installation manuel. For most gas furnaces it is .8. It is very easy to short out the thermostat when making this adjustment, so always have the power off.

If you have a volt meter, remove the thermostat off from the mounting plate and check for 24 volts AC across red (R) and White (W). Then check across Red and Yellow (Y). If you do not find any voltage, follow wire as much as you can all the way back to the air handler that is connected to it. Look inside and see if there is a small Auto (car) type of fuse in the wiring harness. Test and replace if necessary. Jump out the Red and Green terminals on the air handler and replace the door. See if the blower turns on. If so, you have narrowed it to the wiring to the thermostat. If not, you have a power problem and will need a technician.