How to replace the old thermostat?

A thermostat is a highly sensitive control instrument which are used to control central air conditioning units in the home. Replace the old outdated air conditioning thermostats digital display thermostats for more accurate controls. While it has fewer parts to malfunction than the other components of your cooling system, it can be a source of problems.

A thermostat cover that's improperly installed or inadvertently bumped can cause the heater or air conditioner to fail to start. Or the thermostat base may slip out of level, causing it to operate incorrectly. Some older thermostats will have wires marked with letters that do not match any that are on the new thermostat. These wires are not necessary. Wrap the exposed wire end with electrical tape to cover it completely and gently set the unused wire into the wall. A far more common problem, however, is dirt. Dirt can affect the thermostat's calibration and interfere with its operation. 

Maintaining the thermostat on your home air-conditioning window unit is vital to keep the whole system working properly. It won't be a difficult or burdensome task if you follow the guidelines mentioned below. First we need these tools on hand to test or replace a thermostat: screwdriver, volt-ohmmeter or multimeter, the replacement thermostat. The thermostat is located behind the control panel. Replace a faulty thermostat with a new one of the same voltage. The thermostat must be compatible with the heating system. Here's how to replace the Refrigeration Tools: Remove old thermostat. Take faceplate off old unit, and look for mounting screws. Remove screws to release thermostat from wall. Remove wires from back of old thermostat by turning connection screws counterclockwise. Be careful not to let loose wires fall down between walls. Thermostat has special sensing bulb attached to it; this part extends from thermostat into evaporator coil area. Its role is to sense temperature, which is controlled by thermostat. To make replacement easier, tag location of bulb before you remove thermostat. Clip probes of tester to thermostat terminals, and turn temperature control dial to coldest setting. If meter reads zero, thermostat is functioning properly. If reading is higher than zero, replace thermostat with new one of same type. If thermostat is held to control panel or frame with screws, clips, or metal tabs, connect new thermostat the same way the old one was connected. Install mounting screws to secure new thermostat to wall. If thermostat has mercury tube, set unit against level during installation; mercury tube thermostats must be exactly level. Snap faceplate back into place. Make sure new thermostat turns heating/cooling system on and off when temperature setting is adjusted.

Following the easy guidelines in this article will ensure that you can successfully maintain and replace your thermostat when the time comes. 

If the thermostat has more than two lead wires connected to it (not counting the sensing bulb wire) do not try to test or replace it. Instead, call a professional service person.