Identifying voltagesUpdated 8 months ago
Warning! High Voltage!!
Any work with high voltage equipment can be dangerous or even fatal if you do not take proper precautions. You should never work with live wires.
Identifying Wires by Voltage
You can determine which cable is coming from the circuit breaker panel and which cables go to the heater by using a voltmeter. Reference the tables below to determine the identification voltages.
240V installations
L1 to L2 - 240V
Gang Box Wires | Identification Voltages |
Second supply wire (L2) (240V) | Ground to L2 (120V) |
Supply Wire (L1) | Ground to L1 (120V) |
Load Wire | Ground to Load (0V) |
Group/Copper | N/A |
120V Installations
L1 to N - 120V
Gang Box Wires | Identification Voltages |
Neutral Wire | Ground to N (0V) |
Supply Wire (L1) | Ground to L1 (120V) |
Load Wire | Ground to Load (0V) |
Group/Copper | N/A |
120V or 240V System?
There are two quick and straightforward methods to identify the voltage your heating system operates on. It's important to note that these methods are general guidelines and are applicable to most homes. However, some homes may have unique setups, and these guidelines may not be universally applicable.
Method One
Identify the breaker in your electrical panel connected to your thermostat. If you observe a single breaker switch resembling the one depicted in the image below, it is indicative of a 120V setup
If you observe a double breaker, as depicted in the image below, it is indicative of a 240V configuration.
Method 2
If you have a Single Pole breaker - it's indicative of a 120V configuration.
If you have a Double Pole breaker - it's indicative of a 240V
If you are unsure of any of these, Please consult with an electrician! OR Book an installation appointment with a Mysa Pro.
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