FAQ Question for Honeywell Thermostat Model CT3200

  • What is cycle rate (System On-Time Setting)?

    Every heating system type will deliver heat to the house at a slightly different rate. The CT3200 provides you with the flexibility to set the cycle rate adjustment to match your specific heating system, whether it is gas or oil forced air, high efficiency forced air, electric forced air, or baseboard hot water.


  • How do I set the cycle rate (System On-Time Setting)?

    Step #1: Remove the thermostat from the wallplate. Pull the lower right corner of the thermostat toward you until it detaches from the wallplate.
    Step #2: Following the directions on the back of the thermostat or in the table below, adjust the A and B screws to match your system type.
    Step #3: Replace thermostat on the wallplate by lining up the top of the thermostat with the top of the wallplate, and then pushing the thermostat onto the wallplate until it snaps on.

    Heating System A Screw B Screw Fuel Switch
    Warm Air Furnace A - in B - in F
    90 plus High Efficiency Furnace A - out 1 turn B - in F
    Hot Water Boiler A - out 1 turn B - in F
    Electric Furnace A - in B - out 1 turn E



  • Which kind of batteries does the CT3200 require? 

    The CT3200 uses two AA alkaline batteries.


  • Where are the batteries located? 

    The two AA alkaline batteries are located under the battery cover on the left side of the thermostat. The cover is easily removed by pulling from the bottom of the battery cover. There is also a small opening at the bottom of the battery cover if you need to use a coin to release the cover.


  • How often should the batteries be replaced? 

    Although the thermostat has a low battery indicator, replace the batteries once a year to prevent the thermostat and heating/cooling system from shutting down due to a lack of battery power. The optimum schedule would be to replace the batteries every fall before the heating season.



  • Is there a low battery warning?

    Yes! The thermostat's display will read "bAt Lo" 1 to 2 months before the batteries run out completely. Replace the batteries as soon as possible after this indication appears in the display.



  • What does bAt Lo mean in my display?

    As the batteries are running low, a "bAt Lo" indicator will flash for 1 to 2 months before batteries run out completely. Replace the batteries as soon as possible after the indicator starts flashing. After the batteries are completely dead, the "bAt Lo" indicator will disappear, leaving a completely blank display. The thermostat will not operate the heating or cooling system until new batteries are installed.



  • It says bAt Lo in my display, what can I do to clear this? 

    First, replace the batteries with a new set of AA alkaline batteries. If you insert the new batteries within 20 to 30 seconds of removing the old ones, you will not have to reprogram the thermostat. If the bAt Lo indication does not clear itself once new batteries are placed in the device install the batteries backward for 5 seconds, take them out, and reinstall correctly. Eventually 1:00pm should come up and you can reprogram the thermostat.

    You may also want to clean the terminals with electrical contact cleaner and a soft cloth. Do not use a sharp object like a screwdriver or knife to clean terminals as this may cause permanent damage to the coating on the terminals.

    If neither of these options clear the bAt Lo indicator, the thermostat should be replaced.



  • Will the thermostat operate without batteries?

    No. The thermostat requires two AA alkaline batteries to operate.



  • What happens when the batteries go dead?

    The thermostat will provide a 1 to 2 month warning (display will show "bAt Lo") before the batteries go dead. Once the batteries go completely dead, the display will be blank and the thermostat will not operate the heating and/or cooling system. Replacing the batteries once a year should prevent the heating/cooling system from shutting down due to lack of battery power.


  • What is the purpose of the fan operation switch? 

    The thermostat fan operation switch, labeled FUEL SWITCH in the diagram below, is factory-set in the "F" position. This is the correct setting for most systems. If your system is an electric heat system, set the switch to "E". The "E" setting will allow the fan to turn on immediately with the heating or cooling in a system where the G terminal is connected.

    Note: On some electric furnaces, the furnace itself controls the fan. In this case, the switch can be left in the F position. Consult your furnace manufacturer or contractor to determine the fan operation if you are unsure.


  • Why is my thermostat cycling so often?

    Honeywell digital thermostats are designed to maintain temperature within 1F of the setpoint. In heating, the thermostat is factory set for forced air systems. This means lighter heating or cooling loads will change the cycling of your thermostat to shorter on and off times, which is normal for forced air systems. To ensure your thermostat cycle rate is matched to your system type, see "How do I set the cycle rate?"



  • Why did my displayed temperature drop about 50 degrees (slipping into Celsius reading)?

    There is a temperature conversion screw marked "C" on the back of some thermostats. When it is in tight, the thermostat will display temperature in degrees Fahrenheit. When the screw is turned out (lose), the display reads Celsius. Simply backing the screw out, re-tightening, and pressing the RUN PROGRAM key should put your thermostat back into the Fahrenheit mode.



  • Why does this thermostat show a different temperature than another room thermometer? 

    The temperature sensorand radiant heat, an accurate electronic sensor, measures air temperature. The air temperature is affected by the wall temperature and objects in the room which are radiating heat. Its displayed temperature may therefore be different than another thermostat or thermometer. Air movement from behind the wall may also affect the temperature reading on the thermostat. Plugging the opening in the wall behind the thermostat may lessen the changes in temperature due to this type of air movement.



  • Why does the display temperature begin to climb when the cooling system is running? 

    If the displayed temperature climbs when the cooling system is running and it is clear that the house is becoming cooler, this may be the result of high current, causing the inside of the thermostat to heat up. Have your system checked by a local contractor.

  • Why does my thermostat beep?

    This thermostat does not have the capability of making an audible noise such as a beeping. The noise you are hearing is likely from another electronic device which is near the thermostat. Check for a smoke detector or security system.


  • What do I do if my LCD display breaks?

    There are no replacement LCD displays available. If the LCD display breaks on your thermostat, then the thermostat will need to be replaced.


  • Why is there a delay on my Air Conditioning coming on?

    The thermostat has a built-in five-minute delay on a request for air conditioning. This is for the purpose of protecting your air conditioning compressor from short cycling. This allows the pressure in your air conditioning compressor time to stabilize before starting. If your air conditioning has a built-in time delay as well, the two delays will run simultaneously.


  • Why does my thermostat turn off before it reaches my set temperature?

    In order to prevent overshooting your programmed temperature, the CT3200 is designed to shut the system off (in both heating and cooling) before reaching the set point. Shortly thereafter, it will bring the system back on, bringing the room temperature to your programmed temperature. This is considered normal operation. On rare occasions (e.g. very hot afternoons), the thermostat may cycle the system on and off more than once prior to reaching your programmed temperature.


  • Why doesn't my heat and cooling switch between the two automatically?

    The feature called auto changeover is not available on this model of thermostat. This feature allows the heating or cooling equipment to be turned on based on the room temperature demand. This feature is used in climates that would require the heating and cooling equipment to be on in the same day. Say in a dessert or mountain area where you may have cool morning temperatures (that required the heat to run) and hot afternoon temperatures (that require the cooling to run). Models with this feature, like the Chronotherm IV, are available through heating and cooling contractors. 


  • Why do the temperatures appear different than a thermometer I have placed by the thermostat?

    Honeywell digital thermostats are designed to display the room temperature in a way similar to how people sense temperature. This means the thermostat takes into account not just the ambient air temperature but also the reflective temp of objects in the room (i.e., wall and furniture). The thermostat uses two sensing elements to sense and display room temperature. One measures the ambient air temperature while the other measures radiant heat. These two readings are then taken together to give the displayed temperature. The thermostat also rounds the displayed temperature to the current temperature set point. For example, if the thermostat is set for 70 degrees, the displayed temperature will show 70 degrees even if actual room temperature is 69.4 degrees Fahrenheit.


  • It mentions in my owner's manual about needing a relay if my existing thermostat used 3 wires. Who do I contact, and what is this for?

    The installation of a relay is for certain types of three wire, heating only applications. If you have a three wire, heating only application, we recommend talking with a contractor to determine if you will need a relay in order to use this thermostat.



  • How do I switch the thermostat from reading in Fahrenheit to Celsius, and vice versa? 

    On the back of the thermostat, there is a screw labeled C. To display the temperature in Fahrenheit, adjust the screw in. To display the temperature in Celsius, adjust the screw out one turn.


  • I see an arrow pointing towards System On, but there is no heat coming up. What should I do?

    Every time the thermostat makes a call for heat, it will indicate this an arrow pointing towards System On in the display. This means that the thermostat is trying to get the heating system on, but for some reason, the heating system is not responding to that call for heat. You can try to place the thermostat switch in the Off Position for 5 minutes and try again. It is recommended to call your heating and cooling contractor to have your system checked for proper operation.


  • My thermostat misses the program it is set for during the day. This happens a few days during the week, but the other days seem to be fine. What is causing this problem? 

    This thermostat has four program periods for the weekdays, and two for the weekends. This means that all program periods must be set for the exact time and temperature you want the thermostat to maintain during these time periods. It is recommended to recheck your programming, and verify all the times are in chronological order.


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