How To Perfect Honeywell ct87k Calibration [3 Easy Steps]

Your Honeywell ct87k calibration is simple- locate the front dial of your Honeywell ct87k thermostat, then hold the dial with your fingertips and turn the dial right or left to adjust the settings according to your need.

It’s all in short to calibrate your Honeywell CT87K thermostat. But, to handle the process like a professional, keep reading…

3 Steps To Perfect Honeywell ct87k Calibration

Our set of instructions is not only for Honeywell ct87k, rather you will be able to deal with different models of thermostats like RTH7600, focuspro 6000, honeywell T4 thermostat, emerson thermostat and Pro1. Here are 3 easy steps on how to calibrate your Honeywell thermostat:

Step 1: Observing The Device

The first thing you need to do is to make sure of certain things. Inspect the front side of the Honeywell ct87k thermostat. You will most likely find two temperature gauges on the round dial. The upper gauge indicates the desired temperature setting and the lower gauge indicates the actual temperature of the room.

Step 2: Holding the Dial

Now you have to properly hold on to the dial to turn it. Before that, make sure the dials are cleaned and not hot. Then you can proceed to the next step. To get proper control of the dial in order to give it a perfect turn, hold the edge of the dial with your fingertips. 

Step 3: Adjusting The Dial

Now it’s time to turn the dials in order to adjust the temperature. You will see red arrows on both sides of the dial. Turning the dial on to either side will make changes to the temperature. So keep turning the dial, till you reach your desired temperature. 

How To Check Honeywell ct87k Calibration

Sometimes you just know when your thermostat needs maintenance, and sometimes you have to make an inspection to know about the condition and requirement of your device. Knowing about the process of maintenance can help you avoid potential damages to your thermostat and not to struggle with your heater common problems. But before starting the process, you should have the following tools:

  • Thermometer
  • Tape
  • Paper towel
  • Level
  • Screwdriver
  • A new dollar bill

Now let’s get to the main process.

Step 1: Preparing For The Process

To make sure your thermostat is generating perfect heat, you need a thermometer to measure it. In order to perfectly measure the temperature, you have to adjust the thermometer in the proper way. Here’s how you can do it:

  • Choose a clean place on the wall a few inches away from the thermostat
  • Tape your thermometer to the wall 
  • Place a thick layer of paper towel behind the thermometer to prevent it from touching the wall (you have to do this to make sure no external influence affects the thermometer)
  • Close the door and the windows of the room

And now we can proceed to the next step.

Step 2: Get Ready For The Inspection

Now you have to wait for about 15 to 20 minutes to make sure that the mercury in the thermometer stabilizes. After that, record the reading that shows on the thermometer and the thermostat needle. You will have to compare the readings.

Step 3: Determining The Condition

Check the difference between the temperature you record in the previous step. If the difference is more than a degree, then there is a possibility that the thermostat is dirty. You can verify that by examining the thermostat. For that, you have to remove the faceplate first. The faceplate is usually held by friction catch or a snap. So it shouldn’t be difficult for you to remove it.

Now as the internal parts are exposed, you have to blow away all the dust accumulated inside. Keep in mind that you should avoid using:

  • Vacuum cleaner
  • Sandpaper
  • Emery cloth
  • Steel bristle brush

Instead, use a thin and sturdy (preferably a dollar bill) to clean the between of these ports after blowing the dust off. The element of this structure is very delicate, this is why you have to take such measures. 

Step 4: Make Some Adjustments

If your thermostat has a mercury vial inside, you have to use a level in order to make sure that the unit is perfectly straight. In case you find that the thermostat is not straight then here’s what you can do:

  • Loosen up the mounting screws
  • Adjust the thermostat unit till it’s level
  • Tighten the screw

And that is it.  

Step 5: Do A Final Check

After going through the whole process, it’s time to wrap it up. Check the temperature again with the glass thermometer following steps 1 and step 2. This should help you to identify if there is any problem with your Honeywell ct87k thermostat’s calibration. In case you do find a problem, you may need to replace it. 

How To Replace A Faulty Honeywell ct87k Thermostat

In case your Honeywell ct87k thermostat calibration is not working properly, then you will need to replace the part. Here are the 5 simple steps to replace your Honeywell ct87k thermostat like a pro. But before you begin, make sure you have these items.

  • Utility knife
  • Replacement thermostat
  • Level
  • Tape
  • Screwdriver

And now we can get started.

Step 1: Removing The Old Thermostat

In order to replace the thermostat, you have to remove the old one first. Take the faceplate off the old unit. There you will notice mounting screws. Remove these screws to detach the thermostat from the wall.

After that, you have to remove all the wires from the back of the old thermostat. You can do that by turning the connection screws counterclockwise. While you do this, be careful not to let loose of the wires.

Step 2: Preparing The Place

Now that you have made a place for the new thermostat, you have to prepare it. Firstly, scrap the exposed wire with a utility knife till the wire ends shine. You have to make sure they are clean. Then attach the wires to the new Honeywell ct87k thermostat.  Keep in mind that the new thermostat must have the same electrical rating as the old one.

Step 3: Installing The Wiring

Once you are done with wiring the thermostat, push the wires back into the wall and tape up the opening. This will save your thermostat from the effect of cold air accumulated inside of the wall.

Step 4: Setting It All Up

Now install the mounting screws in order to secure the new thermostat to the wall. Set the mercury tube against the level during installation. Keep in mind that the mercury tube thermostats must be exactly level. Otherwise, it won’t work properly. 

Step 5: Finishing It Up

Now for the final touch, simply snap the faceplate back into its place. Just make sure that the newly installed thermostat turns the cooling/heating system on and off when the temperature setting is calibrated. And there you have it.

If you have followed the method we have discussed here, it shouldn’t be a problem for you to replace your honeywell ct87k calibration in less than an hour.


Why is my thermostat not accurate?

The most common reason why thermostats are not accurate is their improper positioning. Your thermostat needs to be perfectly placed. If the thermostat is in direct sunlight or near a heat source, it will not work properly. Another probable reason why your thermostat is not accurate is its in-central location within your home. It prevents your thermostat from giving an accurate reading of temperature. 

How to reset the Honeywell thermostat?

To reset the thermostat of such models you have to- press and hold the menu button, then scroll through till the reset option appears on the display and select reset option. And now you have successfully reset your Honeywell thermostat. 

In Conclusion:

Hope, you could calibrate your Honeywell ct87k thermostat reading our in depth guide. However, if you do have any queries, then the comment box is open for you.

About William

William is the founder of He has real life practical skills in fixing smoker & heating appliance issues. He loves to share his knowledge & helps others in fixing their appliances & saving their money. William firmly believes that anyone can repair his or her unit with the correct guidance & knowledge. See more at about us.

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