60 amp wire choices for boiler

[eugene thomas]

Am installing electric boiler in my shop as backup to propane boiler. Boiler needs 50 amps of power but book says 70 amps. In local big store choices of breaker are 60 and 100 amps. Wire size biggest with out going to main service wire was 6-3 was told that only good for 55 amps. Best solution?????

[John Lanciani]

Supply house.

[eugene thomas]

Ya will have to go to supply house. Talk to company that makes unit. Told me if not go to the 70 amp breaker will trip breaker because unlike motor draws 50 amps for long hall.

[Jim Neeley]

If you're talking a heating system boiler, one option is to downsize your back-up boiler to something that will run on 6-3, recognizing that it may not keep the building to 70F if your propane system goes out during the coldest part of the year. If the propane system went out on a record cold day and you could only heat the building to 60F or 50F or even 40F that may not be the end of the world for a backup system.

There's something to be said for just having enough to avoid freeze up. :-)

Jim