How To Replace Analog Thermostat With Digital

Why am I here?

To save money, save energy, and go green with the installation of a new heat/air conditioning (unit) digital thermostat (stat).

You are familiar with your thermostat as you have used it to keep your home comfortable year round. During this same time you were concerned about the cost to operate the unit unaware the analog stat  you have was costing you money and energy.

This cost, especially in the winter months, was caused by the analog stat’s inability to hold a close temperature range you desired. Therefore you were raising and lowering the stat setting as much as four or five degrees each time to satisfy your needs.

When you increased the setting more than two degrees the emergency heat strip system kicked in unbeknown to you and greatly increase your utility bill. Think a minute, with your current analog system—first you are hot and then cold (in winter) and the opposite (in summer)–uncomfortable.

Now comes along the digital thermostat with the close temperature sensitivity providing your home with greater comfort with less expensive utility bills. These stats come as either programmable or non programmable–your choice.

Install a digital stat that will provide you with an evener temperature throughout your home.  Save money, Save Energy, Go Green.

These digital stats come in programmable and non-programmable in fact some of the newest programmable stats have only three buttons for one to operate—Home-Sleep-Work visible on the stat and in addition many new stats can be controlled from your iphone. Normally, a simple job for the do-it-yourself person.

Note: Programmable thermostats are neat as you can program them once and they will operate 24/7 saving you energy and money.  A bit more expensive at the beginning but gives you a good return on investment. Oh yes, should the power go down for any length of time you will likely have to reprogram the unit.  Keep the instructions just in case.

Lets get that digital stat installed (Replacing Analog Thermostat)

Please remember to turn off the power to your AC unit before proceeding and take all possible safety precautions.

We are going through the procedure in steps.


  1. Disconnect the electric at your main electrical panel by tripping the breakers marked AC to the OFF position.   They are marked ON/OFF.
  2. Be Careful—many heat pumps units have a second breaker—they are NOT always marked correctly in your electrical panel—Check carefully.
  3. Remove the cover (top) of the thermostat. Remove carefully.
  4. Check for wires; there are two types of wires. A: exposed and B: unexposed.
  5. Exposed wires-visible when the cover is off.  Remove wires from terminals and label with tape the letter shown on the old terminal.
  6. Unexposed wires-require the removal of the face plate from the base unit.
  7. Remove wires and label as above.
  8. Removal of face plate- requires a small screw driver to loosen- NOT remove screws.
  9. Remove thermostat base-Screwed to wall with fasteners.  If you plan ahead you will purchase the new unit with a like design—covering and/or using the existing holes.
  10. Thread the wires back through the old base unit being sure to wrap at least one wire around a pencil to prevent losing them in to the hole behind the stat.

You have completed the removal of the old analog stat and ready to install the new stat.


  1. Thread wires through new base and secure it to wall.
  2. Follow instructions included with the thermostat using your color coded wires you marked.
  1. Secure wires to terminals as instructed.  Tighten very secure.
  1. Mount thermostat to base unit. Again, secure screws if required

Note: Many new units have only base and stat (cover) which snaps together.

  1. Install stat (cover) by snapping to base.
  2. Set fan switch (auto/fan) to automatic.
  3. Set system switch (cool/off/heat) to off.
  4. Reset the AC breakers to on at the main panel.
  5. Set system switch to heat or cool based upon the time of year.
  1. Set desired temperature.   New stat will start shortly.


Had you chosen to purchase a programmable thermostat additional step required as follows.

  1. You will need batteries.
  2. You will need to read the enclosed instructions to program the unit to suite your comfort zone.  Normally, this can be completed prior to removing the old stat while setting in your favorite chair-of course you will need to install the batteries.
  3. Upon completing the wiring (as shown above) and installing the programmed stat you will you will save money and energy, not to mention you have joined the green people.
  4. Check all work complete before the last step.

Last Step:  Restore Power. Regardless of which thermostat you purchased—Go to the electric panel and return the AC breakers to the ON position.


You have just completed the installation of your digital thermostat.