Not sure if this is the correct place, so I apologize in advance if this is the wrong forum. I have a Lux TS9600TSa Thermostat that is approximately 9 months old. I currently have the thermostat set at 67 degrees. I noticed that over the winter it would feel cold before the heating system would kick on. Once it did start, the temperature at the thermostat would drop 2-3 degrees within 5 or so minutes. The furnace would run and it would shut off once it reached 1-2 degrees above the set temperature. As a test, I took a wireless temperature probe and set it right above the thermostat. Last night it felt cold again, so I checked the temperature. The thermostat was at 67 degrees, and the wireless probe was at 65.2 degrees. The thermostat is located in the hallway of a small 2 bedroom twin. Is the thermostat defective? Should I try a new one to see if there's a difference? It seems that once the furnace starts, cold air is drawn out of the living/dinning area into the hallway dropping the temperature? Is the hallway insulated enough to cause that much of a temperature difference? The home is heated by a gas furnace that was installed by the previous owner. The heat registers are in the ceilings with low returns in the living room, and master bedroom. There are two high returns in the hallway. Any advice would be appreciated. Thank you for your time.

 

Sounds like the furnace fan is coming on before the burner ignites. First the burner should start and then the fan. Also check " swing setting" on the stat. Sounds like it might be set to high.

 

Heat registers in the ceiling are less then an ideal installation. If those heating ducts aren't insulated extremely well...... they will get cold and when the furnace starts..... blow out all the cold air that is transferred to them.

Can you confirm that model number..... Lux TS9600TSa
Most thermostats can be set for how many times an hour the furnace will fire. The more times an hour..... the closer the temperature tolerance.

 

The model number is correct and is what is written on the included instruction and installation manual. Today there was again a 1+ degree discrepency between the thermostat temperature reading and the wireless thermometer poistioned right next to it.This was a while after the previous cycle had finished. I understand now why the temperature drop may occur due to cold air in the ducting. As an addon, the ducting is large insulated tubes as opposed to metal ductowork. What I don't understand is the discrepency between the thermostat and wireless thermometer temperatures which can be as much as three degrees before the heat finally kicks on. The thermostat has read 67 and the wireless has read 64 on cold days. Thank you.

 

Buy a white Rogers Robert shaw or honeywell stat. The off the wall brand which lux is are usually not up to par. The mentioned stats are industry tested thousands of times and have above average dependability. Also check your grill positioning. Grills should be directed toward outside walls. This to cool or heat area not your body. If heat or air is blowing on you and not across room once it cycles you will find dis comfort.