Looks too easy to be true? It may be
There is no real debate on whether or not an old mercury thermostat should be replaced for a newer digital thermostat. Most people agree that the digital thermostat helps you to regulate the temperature better with a higher level of efficiency. But what do you do when you have the old thermostat and want to replace it with a new one? For a great many people, the solution is just to switch out the device with a local store bought digital solution. However, this may not be the most beneficial way in which to go about changing from mercury to modern. In terms of appliance maintenance and repair, this may be one area in which you will want to have a technician perform the job. Let me explain.
A personal story of financial loss
A few years ago I was updating my house and in the process I decided to switch over the thermostat from mercury to a digital one. As expected, I cut the power from the breaker, I read the instructions meticulously, and I followed everything to the letter. When I turned on the breaker after the install, everything appeared to be running properly. The heat (as it was winter) worked well. I did not give it a second thought. Then the electric bill came in.
Apparently, the thermostat which I had purchased bypassed the emergency heat settings of the HVAC system which I had. As a result, every time that the heat kicked on the emergency heat would also kick on. Basically, there was a double in power. And this double in power resulted in a doubled electrical bill.
Not all wires are created equal
What I learned from this experience is that even though the wires that you have on your air conditioning system are working fine with the thermostat you have now does not mean that they are compatible with the thermostat that you are getting. Even if you get a 5,7,or other multiple which matches your system, you are not ensured that it is made for your machine.
Since the HVAC system is one of the most expensive appliances in the home, it is better to have a licensed professional do the rewiring and work the thermostat in.
Common problems caused by a self-install
Apart from the emergency heat kicking on and running up your electricity bill, there are a number of other problems which can occur when you do a self-install of a thermostat. The most common issues are:
- The wrong wire will be used and the unit will not work at all
- The wire will be connected to the wrong area on the external system causing fuses to blow
- The conductor or other internal units will malfunction and/or explode do to improperly regulated electricity
- Wires will not be secured properly causing the unity to malfunction or stop
- The unit will spark or catch fire due to improper wire installation (such as forgetting to attach the ground wire properly).
- You will void your warranty should you have any problems in the future and it is found out that you did a self-install job instead of having a licensed technician do the work.
But what if you already have a digital thermostat?
If you already have a digital thermostat, then the odds that you will have to replace the wiring on the device is greatly reduced. Ensure that you have the model and make of your HVAC system before replacing the thermostat. Take the front cover off of your thermostat (the same way in which you do so to replace the battery) and take a picture of the wire configuration. Note how many wires are attached to the system and if there are special wires for emergency heating and cooling. Once you have all of this information then seek out a digital replacement which meets the specifications of your system. If you are ever in doubt, have a AC specialist look at your install prior to turning it back on to ensure that you have done everything properly.
Note: it is highly recommended that you NEVER perform any internal maintenance on your HVAC system unless you have been properly trained. Such tampering with the internal components can lead to serious injury including electrocution and/or death. Call the pros at appliance repair phoenix az for their expertise.