why does a water heater mention 120 or 277volts for a water heater designed for 208 to 240 volts?

[cayoung145]

Read all the replies, good info. My question is about the note that mentions that mentions 277 volts. Even A.O. Smith could not tell me why this note was there and what it means. The note says This heater is equipped for non-simultaneous operation on a standard 2 wire circuit. T white for 120 and 277 volts. unit is equipped for 208 volts or 240 volts on plate. Where does the 277 volts come in?

 

[kwired]

Can you be more specific?

Boiler plate type notes that may not all apply to all units?

 

[cayoung145]

note A O SMITH water heater: This heater is equipped for non-simultaneous operation on a standard two wire circuit
t white for 120v and 277v

Why the mention the 277 volts? As an aside, the water heater is being installed in a condo that has a Hilton Hotel with integrated systems. So, there are industrial systems in the building. Elevators, huge hot water heaters, garages, industrial HVAC units, etc. Of course this should have nothing to do with the note on the heater. Any clarification appreciated. I only got into this because the plumber I planned to use mentioned the 277 volts as a possible issue.

 

[Todd0x1]

Its one diagram they use for all their heaters. All they are saying is the wire labeled red on the diagram will be white if the unit is a model that is powered line to neutral which would be a 120 or 277v unit which yours is not.

 

[cayoung145]

thanks much. Seems like the manufacturer's tech person could have explained that.

 

[mtfallsmikey1]

We have 277 volt 40 gallon water heaters in my buildings, We do not convert 240 volt models to 277. All non-simultaneous heaters pretty much use the same wiring scheme regardless of voltage..
Courtesy of the token plumber..